diff --git a/OTEL_EXEMPLARS.md b/OTEL_EXEMPLARS.md
index ea7377251..1034d52be 100644
--- a/OTEL_EXEMPLARS.md
+++ b/OTEL_EXEMPLARS.md
@@ -9,8 +9,8 @@ If you want to see this in action, you can run the example from the `ExemplarsCl
 ```
 ./mvnw package
 cd integration_tests/it_exemplars_otel_agent/target/
-curl -LO https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/download/v1.2.0/opentelemetry-javaagent-all.jar
-java -Dotel.traces.exporter=logging -Dotel.metrics.exporter=none -javaagent:./opentelemetry-javaagent-all.jar -jar ./example-spring-boot-app.jar
+curl -LO https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/download/v1.10.1/opentelemetry-javaagent.jar
+java -Dotel.traces.exporter=logging -Dotel.metrics.exporter=none -javaagent:./opentelemetry-javaagent.jar -jar ./example-spring-boot-app.jar
 ```
 
 Now you have a Spring REST service running on [http://localhost:8080/hello](http://localhost:8080/hello) that is instrumented with the OpenTelemetry Java agent.
diff --git a/README.md b/README.md
index f6fe7a172..b6dd47033 100644
--- a/README.md
+++ b/README.md
@@ -46,25 +46,25 @@ version can be found on in the maven repository for
 <dependency>
   <groupId>io.prometheus</groupId>
   <artifactId>simpleclient</artifactId>
-  <version>0.12.0</version>
+  <version>0.15.0</version>
 </dependency>
 <!-- Hotspot JVM metrics-->
 <dependency>
   <groupId>io.prometheus</groupId>
   <artifactId>simpleclient_hotspot</artifactId>
-  <version>0.12.0</version>
+  <version>0.15.0</version>
 </dependency>
 <!-- Exposition HTTPServer-->
 <dependency>
   <groupId>io.prometheus</groupId>
   <artifactId>simpleclient_httpserver</artifactId>
-  <version>0.12.0</version>
+  <version>0.15.0</version>
 </dependency>
 <!-- Pushgateway exposition-->
 <dependency>
   <groupId>io.prometheus</groupId>
   <artifactId>simpleclient_pushgateway</artifactId>
-  <version>0.12.0</version>
+  <version>0.15.0</version>
 </dependency>
 ```
 
@@ -130,57 +130,86 @@ when using this approach ensure the value you are reporting accounts for concurr
 
 ### Summary
 
-Summaries track the size and number of events.
+Summaries and Histograms can both be used to monitor distributions, like latencies or request sizes.
+
+An overview of when to use Summaries and when to use Histograms can be found on [https://prometheus.io/docs/practices/histograms](https://prometheus.io/docs/practices/histograms).
+
+The following example shows how to measure latencies and request sizes:
 
 ```java
 class YourClass {
-  static final Summary receivedBytes = Summary.build()
-     .name("requests_size_bytes").help("Request size in bytes.").register();
-  static final Summary requestLatency = Summary.build()
-     .name("requests_latency_seconds").help("Request latency in seconds.").register();
 
-  void processRequest(Request req) {
+  private static final Summary requestLatency = Summary.build()
+      .name("requests_latency_seconds")
+      .help("request latency in seconds")
+      .register();
+
+  private static final Summary receivedBytes = Summary.build()
+      .name("requests_size_bytes")
+      .help("request size in bytes")
+      .register();
+
+  public void processRequest(Request req) {
     Summary.Timer requestTimer = requestLatency.startTimer();
     try {
       // Your code here.
     } finally {
-      receivedBytes.observe(req.size());
       requestTimer.observeDuration();
+      receivedBytes.observe(req.size());
     }
   }
 }
 ```
 
-There are utilities for timing code and support for [quantiles](https://prometheus.io/docs/practices/histograms/#quantiles).
-Essentially quantiles aren't aggregatable and add some client overhead for the calculation.
+The `Summary` class provides different utility methods for observing values, like `observe(double)`, `startTimer(); timer.observeDuration()`, `time(Callable)`, etc.
+
+By default, `Summary` metrics provide the `count` and the `sum`. For example, if you measure latencies of a REST service, the `count` will tell you how often the REST service was called, and the `sum` will tell you the total aggregated response time. You can calculate the average response time using a Prometheus query dividing `sum / count`.
+
+In addition to `count` and `sum`, you can configure a Summary to provide quantiles:
 
 ```java
-class YourClass {
-  static final Summary requestLatency = Summary.build()
-    .quantile(0.5, 0.05)   // Add 50th percentile (= median) with 5% tolerated error
-    .quantile(0.9, 0.01)   // Add 90th percentile with 1% tolerated error
-    .name("requests_latency_seconds").help("Request latency in seconds.").register();
+Summary requestLatency = Summary.build()
+    .name("requests_latency_seconds")
+    .help("Request latency in seconds.")
+    .quantile(0.5, 0.01)    // 0.5 quantile (median) with 0.01 allowed error
+    .quantile(0.95, 0.005)  // 0.95 quantile with 0.005 allowed error
+    // ...
+    .register();
+```
 
-  void processRequest(Request req) {
-    requestLatency.time(new Runnable() {
-      public abstract void run() {
-        // Your code here.
-      }
-    });
+As an example, a `0.95` quantile of `120ms` tells you that `95%` of the calls were faster than `120ms`, and `5%` of the calls were slower than `120ms`.
 
+Tracking exact quantiles require a large amount of memory, because all observations need to be stored in a sorted list. Therefore, we allow an error to significantly reduce memory usage.
 
-    // Or the Java 8 lambda equivalent
-    requestLatency.time(() -> {
-      // Your code here.
-    });
-  }
-}
+In the example, the allowed error of `0.005` means that you will not get the exact `0.95` quantile, but anything between the `0.945` quantile and the `0.955` quantile.
+
+Experiments show that the `Summary` typically needs to keep less than 100 samples to provide that precision, even if you have hundreds of millions of observations.
+
+There are a few special cases:
+
+* You can set an allowed error of `0`, but then the `Summary` will keep all observations in memory.
+* You can track the minimum value with `.quantile(0, 0)`. This special case will not use additional memory even though the allowed error is `0`.
+* You can track the maximum value with `.quantile(1, 0)`. This special case will not use additional memory even though the allowed error is `0`.
+
+Typically, you don't want to have a `Summary` representing the entire runtime of the application, but you want to look at a reasonable time interval. `Summary` metrics implement a configurable sliding time window:
+
+```java
+Summary requestLatency = Summary.build()
+    .name("requests_latency_seconds")
+    .help("Request latency in seconds.")
+    .maxAgeSeconds(10 * 60)
+    .ageBuckets(5)
+    // ...
+    .register();
 ```
 
+The default is a time window of 10 minutes and 5 age buckets, i.e. the time window is 10 minutes wide, and * we slide it forward every 2 minutes.
+
 ### Histogram
 
-Histograms track the size and number of events in buckets.
-This allows for aggregatable calculation of quantiles.
+Like Summaries, Histograms can be used to monitor latencies (or other things like request sizes).
+
+An overview of when to use Summaries and when to use Histograms can be found on [https://prometheus.io/docs/practices/histograms](https://prometheus.io/docs/practices/histograms).
 
 ```java
 class YourClass {
diff --git a/benchmarks/pom.xml b/benchmarks/pom.xml
index 76a61bae3..e008615ae 100644
--- a/benchmarks/pom.xml
+++ b/benchmarks/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>benchmarks</artifactId>
@@ -27,17 +27,17 @@
         <dependency>
             <groupId>org.openjdk.jmh</groupId>
             <artifactId>jmh-core</artifactId>
-            <version>1.3.2</version>
+            <version>1.34</version>
         </dependency>
         <dependency>
             <groupId>org.openjdk.jmh</groupId>
             <artifactId>jmh-generator-annprocess</artifactId>
-            <version>1.3.2</version>
+            <version>1.34</version>
         </dependency>
         <dependency>
             <groupId>javax.annotation</groupId>
             <artifactId>javax.annotation-api</artifactId>
-            <version>1.3.1</version>
+            <version>1.3.2</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
diff --git a/benchmarks/src/main/java/io/prometheus/client/CKMSQuantileBenchmark.java b/benchmarks/src/main/java/io/prometheus/client/CKMSQuantileBenchmark.java
new file mode 100644
index 000000000..530810481
--- /dev/null
+++ b/benchmarks/src/main/java/io/prometheus/client/CKMSQuantileBenchmark.java
@@ -0,0 +1,138 @@
+package io.prometheus.client;
+
+import io.prometheus.client.CKMSQuantiles.Quantile;
+import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.infra.Blackhole;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.TimeUnit;
+
+public class CKMSQuantileBenchmark {
+
+    @State(Scope.Benchmark)
+    public static class EmptyBenchmarkState {
+        @Param({"10000", "100000", "1000000"})
+        public int value;
+
+        List<Quantile> quantiles;
+        Random rand = new Random(0);
+
+        List<Double> shuffle;
+
+        Quantile mean = new Quantile(0.50, 0.050);
+        Quantile q90 = new Quantile(0.90, 0.010);
+        Quantile q95 = new Quantile(0.95, 0.005);
+        Quantile q99 = new Quantile(0.99, 0.001);
+
+        @Setup(Level.Trial)
+        public void setup() {
+            quantiles = new ArrayList<Quantile>();
+            quantiles.add(mean);
+            quantiles.add(q90);
+            quantiles.add(q95);
+            quantiles.add(q99);
+
+            shuffle = new ArrayList<Double>(value);
+            for (int i = 0; i < value; i++) {
+                shuffle.add((double) i);
+            }
+            Collections.shuffle(shuffle, rand);
+        }
+    }
+
+    @Benchmark
+    @BenchmarkMode({Mode.AverageTime})
+    @OutputTimeUnit(TimeUnit.MILLISECONDS)
+    public void ckmsQuantileInsertBenchmark(EmptyBenchmarkState state) {
+        CKMSQuantiles q = new CKMSQuantiles(state.quantiles.toArray(new Quantile[]{}));
+        for (Double l : state.shuffle) {
+            q.insert(l);
+        }
+    }
+
+    /** prefilled benchmark, means that we already have a filled and compressed samples available */
+    @State(Scope.Benchmark)
+    public static class PrefilledBenchmarkState {
+        @Param({"10000", "100000", "1000000"})
+        public int value;
+
+
+        CKMSQuantiles ckmsQuantiles;
+
+        List<Quantile> quantiles;
+        Random rand = new Random(0);
+
+        Quantile mean = new Quantile(0.50, 0.050);
+        Quantile q90 = new Quantile(0.90, 0.010);
+        Quantile q95 = new Quantile(0.95, 0.005);
+        Quantile q99 = new Quantile(0.99, 0.001);
+        List<Double> shuffle;
+
+        int rank = (int) (value * q95.quantile);
+
+
+        @Setup(Level.Trial)
+        public void setup() {
+            quantiles = new ArrayList<Quantile>();
+            quantiles.add(mean);
+            quantiles.add(q90);
+            quantiles.add(q95);
+            quantiles.add(q99);
+
+            shuffle = new ArrayList<Double>(value);
+            for (int i = 0; i < value; i++) {
+                shuffle.add((double) i);
+            }
+            Collections.shuffle(shuffle, rand);
+
+
+            ckmsQuantiles = new CKMSQuantiles(quantiles.toArray(new Quantile[]{}));
+            for (Double l : shuffle) {
+                ckmsQuantiles.insert(l);
+            }
+            // make sure we inserted all 'hanging' samples (count % 128)
+            ckmsQuantiles.get(0);
+            // compress everything so we have a similar samples size regardless of n.
+            ckmsQuantiles.compress();
+            System.out.println("Sample size is: " + ckmsQuantiles.samples.size());
+        }
+
+    }
+
+    @Benchmark
+    @BenchmarkMode({Mode.AverageTime})
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void ckmsQuantileGetBenchmark(Blackhole blackhole, PrefilledBenchmarkState state) {
+        blackhole.consume(state.ckmsQuantiles.get(state.q90.quantile));
+    }
+
+    /**
+     * benchmark for the f method.
+     */
+    @Benchmark
+    @BenchmarkMode({Mode.AverageTime})
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public void ckmsQuantileF(Blackhole blackhole, PrefilledBenchmarkState state) {
+        blackhole.consume(state.ckmsQuantiles.f(state.rank));
+    }
+
+    public static void main(String[] args) throws RunnerException {
+
+        Options opt = new OptionsBuilder()
+                .include(CKMSQuantileBenchmark.class.getSimpleName())
+                .warmupIterations(5)
+                .measurementIterations(4)
+                .threads(1)
+                .forks(1)
+                .build();
+
+        new Runner(opt).run();
+    }
+}
diff --git a/integration_tests/it_common/pom.xml b/integration_tests/it_common/pom.xml
index bebfe330e..05bc4a886 100644
--- a/integration_tests/it_common/pom.xml
+++ b/integration_tests/it_common/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_common</artifactId>
diff --git a/integration_tests/it_exemplars_otel_agent/pom.xml b/integration_tests/it_exemplars_otel_agent/pom.xml
index 69a4f6d3d..2ac1266d7 100644
--- a/integration_tests/it_exemplars_otel_agent/pom.xml
+++ b/integration_tests/it_exemplars_otel_agent/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_exemplars_otel_agent</artifactId>
@@ -16,7 +16,7 @@
       <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-dependencies</artifactId>
-        <version>2.4.4</version>
+        <version>2.6.3</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>
@@ -56,7 +56,7 @@
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
-      <version>1.2.0</version>
+      <version>1.2.10</version>
       <scope>test</scope>
     </dependency>
     <dependency>
diff --git a/integration_tests/it_exemplars_otel_agent/src/test/java/io/prometheus/client/it/exemplars_otel_agent/ExemplarsOpenTelemetryAgentIT.java b/integration_tests/it_exemplars_otel_agent/src/test/java/io/prometheus/client/it/exemplars_otel_agent/ExemplarsOpenTelemetryAgentIT.java
index 094f04fb6..7736f3595 100644
--- a/integration_tests/it_exemplars_otel_agent/src/test/java/io/prometheus/client/it/exemplars_otel_agent/ExemplarsOpenTelemetryAgentIT.java
+++ b/integration_tests/it_exemplars_otel_agent/src/test/java/io/prometheus/client/it/exemplars_otel_agent/ExemplarsOpenTelemetryAgentIT.java
@@ -25,13 +25,13 @@
 public class ExemplarsOpenTelemetryAgentIT {
 
   private final String image = "openjdk:11-jre";
-  private final String otelAgentVersion = "1.2.0";
+  private final String otelAgentVersion = "1.10.1";
   private final Volume volume;
   private final GenericContainer<?> javaContainer;
 
   public ExemplarsOpenTelemetryAgentIT() throws IOException, URISyntaxException {
     String appJar = "example-spring-boot-app.jar";
-    String agentJar = "opentelemetry-javaagent-all.jar";
+    String agentJar = "opentelemetry-javaagent.jar";
     String agentDownloadUrl = "https://github.com/open-telemetry/opentelemetry-java-instrumentation/" +
             "releases/download/v" + otelAgentVersion + "/" + agentJar;
     Downloader.downloadToTarget(agentDownloadUrl, agentJar);
diff --git a/integration_tests/it_exemplars_otel_sdk/pom.xml b/integration_tests/it_exemplars_otel_sdk/pom.xml
index adebc1d9d..aa9096d94 100644
--- a/integration_tests/it_exemplars_otel_sdk/pom.xml
+++ b/integration_tests/it_exemplars_otel_sdk/pom.xml
@@ -5,14 +5,14 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_exemplars_otel_sdk</artifactId>
   <name>Integration Tests - Exemplars with OpenTelemetry</name>
 
   <properties>
-    <otel.version>1.2.0</otel.version>
+    <otel.version>1.10.1</otel.version>
   </properties>
 
   <dependencies>
diff --git a/integration_tests/it_java_versions/pom.xml b/integration_tests/it_java_versions/pom.xml
index 43e7f5853..3d3c86f75 100644
--- a/integration_tests/it_java_versions/pom.xml
+++ b/integration_tests/it_java_versions/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_java_versions</artifactId>
@@ -78,8 +78,6 @@
         <configuration>
           <source>1.6</source>
           <target>1.6</target>
-          <!-- Intellij users: Intellij currently does not support different Java versions -->
-          <!-- for sources and test sources, see https://youtrack.jetbrains.com/issue/IDEA-85478 -->
           <testSource>1.8</testSource>
           <testTarget>1.8</testTarget>
         </configuration>
@@ -91,6 +89,36 @@
     </plugins>
   </build>
 
+  <profiles>
+    <profile>
+      <!-- Intellij does not support different Java versions for source and testSource -->
+      <!-- As a workaround, use Java 8 in Intellij. -->
+      <!-- This will be fixed with https://youtrack.jetbrains.com/issue/IDEA-85478 -->
+      <id>intellij</id>
+      <activation>
+        <activeByDefault>false</activeByDefault>
+        <property>
+          <!-- This property is only set when you open the project in Intellij. -->
+          <!-- When you compile in the command line, the property will not be set -->
+          <!-- and this profile will not be used. -->
+          <name>idea.maven.embedder.version</name>
+        </property>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+              <source>1.8</source>
+              <target>1.8</target>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+  </profiles>
+
   <licenses>
     <license>
       <name>The Apache Software License, Version 2.0</name>
diff --git a/integration_tests/it_log4j2/pom.xml b/integration_tests/it_log4j2/pom.xml
index 8b792d908..15f296931 100644
--- a/integration_tests/it_log4j2/pom.xml
+++ b/integration_tests/it_log4j2/pom.xml
@@ -5,14 +5,14 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>integration_tests</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>it_log4j2</artifactId>
     <name>Integration Tests - log4j2</name>
 
     <properties>
-        <log4j2.version>2.17.0</log4j2.version>
+        <log4j2.version>2.17.1</log4j2.version>
         <!-- I manually tested this with log4j2.version 2.3 and Java 6, and it worked fine. -->
         <!-- <log4j2.version>2.3</log4j2.version> -->
     </properties>
@@ -97,8 +97,6 @@
                     <!-- downgrade to log4j 2.3 to run a quick test with Java 6. -->
                     <source>1.6</source>
                     <target>1.6</target>
-                    <!-- Intellij users: Intellij currently does not support different Java versions -->
-                    <!-- for sources and test sources, see https://youtrack.jetbrains.com/issue/IDEA-85478 -->
                     <testSource>1.8</testSource>
                     <testTarget>1.8</testTarget>
                 </configuration>
@@ -110,6 +108,36 @@
         </plugins>
     </build>
 
+    <profiles>
+        <profile>
+            <!-- Intellij does not support different Java versions for source and testSource -->
+            <!-- As a workaround, use Java 8 in Intellij. -->
+            <!-- This will be fixed with https://youtrack.jetbrains.com/issue/IDEA-85478 -->
+            <id>intellij</id>
+            <activation>
+                <activeByDefault>false</activeByDefault>
+                <property>
+                    <!-- This property is only set when you open the project in Intellij. -->
+                    <!-- When you compile in the command line, the property will not be set -->
+                    <!-- and this profile will not be used. -->
+                    <name>idea.maven.embedder.version</name>
+                </property>
+            </activation>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-compiler-plugin</artifactId>
+                        <configuration>
+                            <source>1.8</source>
+                            <target>1.8</target>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
+
     <licenses>
         <license>
             <name>The Apache Software License, Version 2.0</name>
diff --git a/integration_tests/it_pushgateway/pom.xml b/integration_tests/it_pushgateway/pom.xml
index a64f0efff..f199d5601 100644
--- a/integration_tests/it_pushgateway/pom.xml
+++ b/integration_tests/it_pushgateway/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_pushgateway</artifactId>
@@ -30,13 +30,13 @@
     <dependency>
       <groupId>com.squareup.okhttp3</groupId>
       <artifactId>okhttp</artifactId>
-      <version>4.9.1</version>
+      <version>4.9.3</version>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
-      <version>1.2.0</version>
+      <version>1.2.10</version>
       <scope>test</scope>
     </dependency>
     <dependency>
@@ -75,8 +75,6 @@
         <configuration>
           <source>1.6</source>
           <target>1.6</target>
-          <!-- Intellij users: Intellij currently does not support different Java versions -->
-          <!-- for sources and test sources, see https://youtrack.jetbrains.com/issue/IDEA-85478 -->
           <testSource>1.8</testSource>
           <testTarget>1.8</testTarget>
         </configuration>
@@ -88,6 +86,36 @@
     </plugins>
   </build>
 
+  <profiles>
+    <profile>
+      <!-- Intellij does not support different Java versions for source and testSource -->
+      <!-- As a workaround, use Java 8 in Intellij. -->
+      <!-- This will be fixed with https://youtrack.jetbrains.com/issue/IDEA-85478 -->
+      <id>intellij</id>
+      <activation>
+        <activeByDefault>false</activeByDefault>
+        <property>
+          <!-- This property is only set when you open the project in Intellij. -->
+          <!-- When you compile in the command line, the property will not be set -->
+          <!-- and this profile will not be used. -->
+          <name>idea.maven.embedder.version</name>
+        </property>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+              <source>1.8</source>
+              <target>1.8</target>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+  </profiles>
+
   <licenses>
     <license>
       <name>The Apache Software License, Version 2.0</name>
diff --git a/integration_tests/it_servlet_jakarta_exporter_webxml/pom.xml b/integration_tests/it_servlet_jakarta_exporter_webxml/pom.xml
index bb9a40da1..072b567c9 100644
--- a/integration_tests/it_servlet_jakarta_exporter_webxml/pom.xml
+++ b/integration_tests/it_servlet_jakarta_exporter_webxml/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>integration_tests</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>it_servlet_jakarta_exporter_webxml</artifactId>
@@ -35,7 +35,7 @@
     <dependency>
       <groupId>com.squareup.okhttp3</groupId>
       <artifactId>okhttp</artifactId>
-      <version>4.9.1</version>
+      <version>4.9.3</version>
     </dependency>
     <dependency>
       <groupId>org.testcontainers</groupId>
@@ -45,7 +45,7 @@
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
-      <version>1.2.0</version>
+      <version>1.2.10</version>
     </dependency>
       <dependency>
           <groupId>jakarta.servlet</groupId>
diff --git a/integration_tests/pom.xml b/integration_tests/pom.xml
index 280040fb3..eeacb74b8 100644
--- a/integration_tests/pom.xml
+++ b/integration_tests/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>integration_tests</artifactId>
@@ -56,7 +56,7 @@
         <dependency>
             <groupId>org.testcontainers</groupId>
             <artifactId>testcontainers</artifactId>
-            <version>1.15.2</version>
+            <version>1.16.3</version>
             <scope>test</scope>
         </dependency>
           <dependency>
@@ -68,7 +68,7 @@
           <dependency>
               <groupId>ch.qos.logback</groupId>
               <artifactId>logback-classic</artifactId>
-              <version>1.2.0</version>
+              <version>1.2.10</version>
               <scope>test</scope>
           </dependency>
       </dependencies>
diff --git a/pom.xml b/pom.xml
index 85d3c4ea3..1e4fb9d8b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
 
     <groupId>io.prometheus</groupId>
     <artifactId>parent</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
 
     <name>Prometheus Java Suite</name>
     <url>http://github.com/prometheus/client_java</url>
@@ -25,7 +25,7 @@
         <connection>scm:git:git@github.com:prometheus/client_java.git</connection>
         <developerConnection>scm:git:git@github.com:prometheus/client_java.git</developerConnection>
         <url>git@github.com:prometheus/client_java.git</url>
-        <tag>parent-0.14.1</tag>
+        <tag>HEAD</tag>
     </scm>
 
     <developers>
@@ -173,8 +173,8 @@
                 </executions>
             </plugin>
             <plugin>
-                <artifactId>maven-release-plugin</artifactId>
                 <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-release-plugin</artifactId>
                 <configuration>
                   <autoVersionSubmodules>true</autoVersionSubmodules>
                   <useReleaseProfile>false</useReleaseProfile>
@@ -183,8 +183,8 @@
                 </configuration>
             </plugin>
             <plugin>
-                <artifactId>maven-deploy-plugin</artifactId>
                 <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-deploy-plugin</artifactId>
             </plugin>
             <plugin>
                 <groupId>org.apache.felix</groupId>
diff --git a/simpleclient/pom.xml b/simpleclient/pom.xml
index 3cc8b7845..c0067869a 100644
--- a/simpleclient/pom.xml
+++ b/simpleclient/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient</artifactId>
@@ -54,5 +54,11 @@
       <version>4.13.2</version>
       <scope>test</scope>
     </dependency>
+      <dependency>
+          <groupId>org.apache.commons</groupId>
+          <artifactId>commons-math3</artifactId>
+          <version>3.6.1</version>
+          <scope>test</scope>
+      </dependency>
   </dependencies>
 </project>
diff --git a/simpleclient/src/main/java/io/prometheus/client/CKMSQuantiles.java b/simpleclient/src/main/java/io/prometheus/client/CKMSQuantiles.java
index 1ffb65382..78126efc8 100644
--- a/simpleclient/src/main/java/io/prometheus/client/CKMSQuantiles.java
+++ b/simpleclient/src/main/java/io/prometheus/client/CKMSQuantiles.java
@@ -1,15 +1,9 @@
 package io.prometheus.client;
 
-// Copied from https://raw.githubusercontent.com/Netflix/ocelli/master/ocelli-core/src/main/java/netflix/ocelli/stats/CKMSQuantiles.java
+// The original implementation was copied from
+// https://raw.githubusercontent.com/Netflix/ocelli/master/ocelli-core/src/main/java/netflix/ocelli/stats/CKMSQuantiles.java
 // Revision d0357b8bf5c17a173ce94d6b26823775b3f999f6 from Jan 21, 2015.
-//
-// This is the original code except for the following modifications:
-//
-//  - Changed the type of the observed values from int to double.
-//  - Removed the Quantiles interface and corresponding @Override annotations.
-//  - Changed the package name.
-//  - Make get() return NaN when no sample was observed.
-//  - Make class package private
+// However, it has been heavily refactored in the meantime.
 
 /*
  Copyright 2012 Andrew Wang (andrew@umbrant.com)
@@ -28,266 +22,275 @@
  */
 
 import java.util.Arrays;
+import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.ListIterator;
 
 /**
- * Implementation of the Cormode, Korn, Muthukrishnan, and Srivastava algorithm
- * for streaming calculation of targeted high-percentile epsilon-approximate
- * quantiles.
- * 
- * This is a generalization of the earlier work by Greenwald and Khanna (GK),
- * which essentially allows different error bounds on the targeted quantiles,
- * which allows for far more efficient calculation of high-percentiles.
- * 
- * 
- * See: Cormode, Korn, Muthukrishnan, and Srivastava
- * "Effective Computation of Biased Quantiles over Data Streams" in ICDE 2005
- * 
- * Greenwald and Khanna,
- * "Space-efficient online computation of quantile summaries" in SIGMOD 2001
- * 
+ * Algorithm solving the "Targeted Quantile Problem" as described in
+ * "Effective Computation of Biased Quantiles over Data Streams"
+ * by Cormode, Korn, Muthukrishnan, and Srivastava.
+ *
  */
-class CKMSQuantiles {
-    /**
-     * Total number of items in stream.
-     */
-    private int count = 0;
+final class CKMSQuantiles {
+
+    final Quantile[] quantiles;
 
     /**
-     * Used for tracking incremental compression.
+     * Total number of observations (not including those that are still in the buffer).
      */
-    private int compressIdx = 0;
+    int n = 0;
 
     /**
-     * Current list of sampled items, maintained in sorted order with error
-     * bounds.
+     * List of sampled observations, ordered by Sample.value.
      */
-    protected LinkedList<Item> sample;
+    final LinkedList<Sample> samples = new LinkedList<Sample>();
 
     /**
-     * Buffers incoming items to be inserted in batch.
+     * Compress is called every compressInterval inserts.
+     * Note that the buffer is flushed whenever get() is called, so we
+     * cannot just wait until the buffer is full before we call compress.
      */
-    private double[] buffer = new double[500];
-
-    private int bufferCount = 0;
+    private final int compressInterval = 128;
+    private int insertsSinceLastCompress = 0;
 
     /**
-     * Array of Quantiles that we care about, along with desired error.
+     * Note that the buffer size could as well be less than the compressInterval.
+     * However, the buffer size should not be greater than the compressInterval,
+     * because the compressInterval is not respected in flush(), so if you want
+     * to compress more often than calling flush() that won't work.
      */
-    private final Quantile quantiles[];
+    private final double[] buffer = new double[compressInterval];
+    private int bufferPos = 0;
 
-    public CKMSQuantiles(Quantile[] quantiles) {
+    public CKMSQuantiles(Quantile... quantiles) {
+        if (quantiles.length == 0) {
+            throw new IllegalArgumentException("quantiles cannot be empty");
+        }
         this.quantiles = quantiles;
-        this.sample = new LinkedList<Item>();
     }
 
     /**
-     * Add a new value from the stream.
-     * 
-     * @param value
+     * Add an observed value
      */
     public void insert(double value) {
-        buffer[bufferCount] = value;
-        bufferCount++;
+        buffer[bufferPos++] = value;
+
+        if (bufferPos == buffer.length) {
+            flush();
+        }
 
-        if (bufferCount == buffer.length) {
-            insertBatch();
+        if (++insertsSinceLastCompress == compressInterval) {
             compress();
+            insertsSinceLastCompress = 0;
         }
     }
 
+    private void flush() {
+        Arrays.sort(buffer, 0, bufferPos);
+        insertBatch(buffer, bufferPos);
+        bufferPos = 0;
+    }
+
     /**
-     * Get the estimated value at the specified quantile.
-     * 
-     * @param q
-     *            Queried quantile, e.g. 0.50 or 0.99.
-     * @return Estimated value at that quantile.
+     * Inserts the elements from index 0 to index toIndex from the sortedBuffer.
      */
-    public double get(double q) {
-        // clear the buffer
-        insertBatch();
-        compress();
-
-        if (sample.size() == 0) {
-            return Double.NaN;
+    void insertBatch(double[] sortedBuffer, int toIndex) {
+        if (toIndex == 0) {
+            return;
         }
-
-        int rankMin = 0;
-        int desired = (int) (q * count);
-
-        ListIterator<Item> it = sample.listIterator();
-        Item prev, cur;
-        cur = it.next();
-        while (it.hasNext()) {
-            prev = cur;
-            cur = it.next();
-
-            rankMin += prev.g;
-
-            if (rankMin + cur.g + cur.delta > desired
-                    + (allowableError(desired) / 2)) {
-                return prev.value;
+        ListIterator<Sample> iterator = samples.listIterator();
+        int i = 0; // position in buffer
+        int r = 0; // sum of g's left of the current sample
+        while (iterator.hasNext() && i < toIndex) {
+            Sample item = iterator.next();
+            while (i < toIndex) {
+                if (sortedBuffer[i] > item.value) {
+                    break;
+                }
+                insertBefore(iterator, sortedBuffer[i], r);
+                r++; // new item with g=1 was inserted before, so increment r
+                i++;
+                n++;
             }
+            r += item.g;
         }
+        while (i < toIndex) {
+            samples.add(new Sample(sortedBuffer[i], 0));
+            i++;
+            n++;
+        }
+    }
 
-        // edge case of wanting max value
-        return sample.getLast().value;
+    private void insertBefore(ListIterator<Sample> iterator, double value, int r) {
+        if (!iterator.hasPrevious()) {
+            samples.addFirst(new Sample(value, 0));
+        } else {
+            iterator.previous();
+            iterator.add(new Sample(value, f(r) - 1));
+            iterator.next();
+        }
     }
 
     /**
-     * Specifies the allowable error for this rank, depending on which quantiles
-     * are being targeted.
-     * 
-     * This is the f(r_i, n) function from the CKMS paper. It's basically how
-     * wide the range of this rank can be.
-     * 
-     * @param rank
-     *            the index in the list of samples
+     * Get the estimated value at the specified quantile.
      */
-    private double allowableError(int rank) {
-        // NOTE: according to CKMS, this should be count, not size, but this
-        // leads
-        // to error larger than the error bounds. Leaving it like this is
-        // essentially a HACK, and blows up memory, but does "work".
-        // int size = count;
-        int size = sample.size();
-        double minError = size + 1;
+    public double get(double q) {
+        flush();
 
-        for (Quantile q : quantiles) {
-            double error;
-            if (rank <= q.quantile * size) {
-                error = q.u * (size - rank);
-            } else {
-                error = q.v * rank;
-            }
-            if (error < minError) {
-                minError = error;
-            }
+        if (samples.size() == 0) {
+            return Double.NaN;
         }
 
-        return minError;
-    }
-
-    private boolean insertBatch() {
-        if (bufferCount == 0) {
-            return false;
+        if (q == 0.0) {
+            return samples.getFirst().value;
         }
 
-        Arrays.sort(buffer, 0, bufferCount);
-
-        // Base case: no samples
-        int start = 0;
-        if (sample.size() == 0) {
-            Item newItem = new Item(buffer[0], 1, 0);
-            sample.add(newItem);
-            start++;
-            count++;
+        if (q == 1.0) {
+            return samples.getLast().value;
         }
 
-        ListIterator<Item> it = sample.listIterator();
-        Item item = it.next();
-
-        for (int i = start; i < bufferCount; i++) {
-            double v = buffer[i];
-            while (it.nextIndex() < sample.size() && item.value < v) {
-                item = it.next();
+        int r = 0; // sum of g's left of the current sample
+        int desiredRank = (int) Math.ceil(q * n);
+        int upperBound = desiredRank + f(desiredRank) / 2;
+
+        ListIterator<Sample> iterator = samples.listIterator();
+        while (iterator.hasNext()) {
+            Sample sample = iterator.next();
+            if (r + sample.g + sample.delta > upperBound) {
+                iterator.previous(); // roll back the item.next() above
+                if (iterator.hasPrevious()) {
+                    Sample result = iterator.previous();
+                    return result.value;
+                } else {
+                    return sample.value;
+                }
             }
+            r += sample.g;
+        }
+        return samples.getLast().value;
+    }
 
-            // If we found that bigger item, back up so we insert ourselves
-            // before it
-            if (item.value > v) {
-                it.previous();
+    /**
+     * Error function, as in definition 5 of the paper.
+     */
+    int f(int r) {
+        int minResult = Integer.MAX_VALUE;
+        for (Quantile q : quantiles) {
+            if (q.quantile == 0 || q.quantile == 1) {
+                continue;
             }
-
-            // We use different indexes for the edge comparisons, because of the
-            // above
-            // if statement that adjusts the iterator
-            int delta;
-            if (it.previousIndex() == 0 || it.nextIndex() == sample.size()) {
-                delta = 0;
-            } 
-            else {
-                delta = ((int) Math.floor(allowableError(it.nextIndex()))) - 1;
+            int result;
+            // We had a numerical error here with the following example:
+            // quantile = 0.95, epsilon = 0.01, (n-r) = 30.
+            // The expected result of (2*0.01*30)/(1-0.95) is 12. The actual result is 11.99999999999999.
+            // To avoid running into these types of error we add 0.00000000001 before rounding down.
+            if (r >= q.quantile * n) {
+                result = (int) (q.v * r + 0.00000000001);
+            } else {
+                result = (int) (q.u * (n - r) + 0.00000000001);
+            }
+            if (result < minResult) {
+                minResult = result;
             }
-
-            Item newItem = new Item(v, 1, delta);
-            it.add(newItem);
-            count++;
-            item = newItem;
         }
-
-        bufferCount = 0;
-        return true;
+        return Math.max(minResult, 1);
     }
 
     /**
-     * Try to remove extraneous items from the set of sampled items. This checks
-     * if an item is unnecessary based on the desired error bounds, and merges
-     * it with the adjacent item if it is.
+     * Merge pairs of consecutive samples if this doesn't violate the error function.
      */
-    private void compress() {
-        if (sample.size() < 2) {
+    void compress() {
+        if (samples.size() < 3) {
             return;
         }
-
-        ListIterator<Item> it = sample.listIterator();
-        int removed = 0;
-
-        Item prev = null;
-        Item next = it.next();
-
-        while (it.hasNext()) {
-            prev = next;
-            next = it.next();
-
-            if (prev.g + next.g + next.delta <= allowableError(it.previousIndex())) {
-                next.g += prev.g;
-                // Remove prev. it.remove() kills the last thing returned.
-                it.previous();
-                it.previous();
-                it.remove();
-                // it.next() is now equal to next, skip it back forward again
-                it.next();
-                removed++;
+        Iterator<Sample> descendingIterator = samples.descendingIterator();
+        int r = n; // n is equal to the sum of the g's of all samples
+
+        Sample right;
+        Sample left = descendingIterator.next();
+        r -= left.g;
+
+        while (descendingIterator.hasNext()) {
+            right = left;
+            left = descendingIterator.next();
+            r = r - left.g;
+            if (left == samples.getFirst()) {
+                // The min sample must never be merged.
+                break;
+            }
+            if (left.g + right.g + right.delta < f(r)) {
+                right.g += left.g;
+                descendingIterator.remove();
+                left = right;
             }
         }
     }
 
-    private class Item {
-        public final double value;
-        public int g;
-        public final int delta;
+    static class Sample {
+
+        /**
+         * Observed value.
+         */
+        final double value;
+
+        /**
+         * Difference between the lowest possible rank of this sample and its predecessor.
+         * This always starts with 1, but will be updated when compress() merges Samples.
+         */
+        int g = 1;
+
+        /**
+         * Difference between the greatest possible rank of this sample and the lowest possible rank of this sample.
+         */
+        final int delta;
 
-        public Item(double value, int lower_delta, int delta) {
+        Sample(double value, int delta) {
             this.value = value;
-            this.g = lower_delta;
             this.delta = delta;
         }
 
         @Override
         public String toString() {
-            return String.format("I{val=%.3f, g=%d, del=%d}", value, g, delta);
+            return String.format("Sample{val=%.3f, g=%d, delta=%d}", value, g, delta);
         }
     }
 
-    public static class Quantile {
-        public final double quantile;
-        public final double error;
-        public final double u;
-        public final double v;
+    static class Quantile {
+
+        /**
+         * Quantile. Must be between 0 and 1.
+         */
+        final double quantile;
+
+        /**
+         * Allowed error. Must be between 0 and 1.
+         */
+        final double epsilon;
+
+        /**
+         * Helper used in the error function f(), see definition 5 in the paper.
+         */
+        final double u;
+
+        /**
+         * Helper used in the error function f(), see definition 5 in the paper.
+         */
+        final double v;
+
+        Quantile(double quantile, double epsilon) {
+            if (quantile < 0.0 || quantile > 1.0) throw new IllegalArgumentException("Quantile must be between 0 and 1");
+            if (epsilon < 0.0 || epsilon > 1.0) throw new IllegalArgumentException("Epsilon must be between 0 and 1");
 
-        public Quantile(double quantile, double error) {
             this.quantile = quantile;
-            this.error = error;
-            u = 2.0 * error / (1.0 - quantile);
-            v = 2.0 * error / quantile;
+            this.epsilon = epsilon;
+            u = 2.0 * epsilon / (1.0 - quantile); // if quantile == 1 this will be Double.NaN
+            v = 2.0 * epsilon / quantile; // if quantile == 0 this will be Double.NaN
         }
 
         @Override
         public String toString() {
-            return String.format("Q{q=%.3f, eps=%.3f}", quantile, error);
+            return String.format("Quantile{q=%.3f, epsilon=%.3f}", quantile, epsilon);
         }
     }
-
 }
diff --git a/simpleclient/src/main/java/io/prometheus/client/SimpleCollector.java b/simpleclient/src/main/java/io/prometheus/client/SimpleCollector.java
index ec321ba0a..5c5bf7c37 100644
--- a/simpleclient/src/main/java/io/prometheus/client/SimpleCollector.java
+++ b/simpleclient/src/main/java/io/prometheus/client/SimpleCollector.java
@@ -11,7 +11,7 @@
  * <p>
  * This class handles common initialization and label logic for the standard metrics.
  * You should never subclass this class.
- * <p>
+ *
  * <h2>Initialization</h2>
  * After calling build() on a subclass, {@link Builder#name(String) name},
  * {@link SimpleCollector.Builder#help(String) help},
diff --git a/simpleclient/src/main/java/io/prometheus/client/Summary.java b/simpleclient/src/main/java/io/prometheus/client/Summary.java
index 34b123ba0..8836cbe7d 100644
--- a/simpleclient/src/main/java/io/prometheus/client/Summary.java
+++ b/simpleclient/src/main/java/io/prometheus/client/Summary.java
@@ -13,70 +13,91 @@
 import java.util.concurrent.TimeUnit;
 
 /**
- * Summary metric, to track the size of events.
+ * {@link Summary} metrics and {@link Histogram} metrics can both be used to monitor distributions like latencies or request sizes.
  * <p>
- * Example of uses for Summaries include:
- * <ul>
- *  <li>Response latency</li>
- *  <li>Request size</li>
- * </ul>
- *
+ * An overview of when to use Summaries and when to use Histograms can be found on <a href="https://prometheus.io/docs/practices/histograms">https://prometheus.io/docs/practices/histograms</a>.
  * <p>
- * Example Summaries:
+ * The following example shows how to measure latencies and request sizes:
+ *
  * <pre>
- * {@code
- *   class YourClass {
- *     static final Summary receivedBytes = Summary.build()
- *         .name("requests_size_bytes").help("Request size in bytes.").register();
- *     static final Summary requestLatency = Summary.build()
- *         .name("requests_latency_seconds").help("Request latency in seconds.").register();
+ * class YourClass {
  *
- *     void processRequest(Request req) {
- *        Summary.Timer requestTimer = requestLatency.startTimer();
- *        try {
- *          // Your code here.
- *        } finally {
- *          receivedBytes.observe(req.size());
- *          requestTimer.observeDuration();
- *        }
- *     }
+ *   private static final Summary requestLatency = Summary.build()
+ *       .name("requests_latency_seconds")
+ *       .help("request latency in seconds")
+ *       .register();
+ *
+ *   private static final Summary receivedBytes = Summary.build()
+ *       .name("requests_size_bytes")
+ *       .help("request size in bytes")
+ *       .register();
  *
- *     // Or if using Java 8 and lambdas.
- *     void processRequestLambda(Request req) {
+ *   public void processRequest(Request req) {
+ *     Summary.Timer requestTimer = requestLatency.startTimer();
+ *     try {
+ *       // Your code here.
+ *     } finally {
+ *       requestTimer.observeDuration();
  *       receivedBytes.observe(req.size());
- *       requestLatency.time(() -> {
- *         // Your code here.
- *       });
  *     }
- * }
+ *   }
  * }
  * </pre>
- * This would allow you to track request rate, average latency and average request size.
  *
+ * The {@link Summary} class provides different utility methods for observing values, like {@link #observe(double)},
+ * {@link #startTimer()} and {@link Timer#observeDuration()}, {@link #time(Callable)}, etc.
  * <p>
- * How to add custom quantiles:
+ * By default, {@link Summary} metrics provide the {@code count} and the {@code sum}. For example, if you measure
+ * latencies of a REST service, the {@code count} will tell you how often the REST service was called,
+ * and the {@code sum} will tell you the total aggregated response time.
+ * You can calculate the average response time using a Prometheus query dividing {@code sum / count}.
+ * <p>
+ * In addition to {@code count} and {@code sum}, you can configure a Summary to provide quantiles:
+ *
  * <pre>
- * {@code
- *     static final Summary myMetric = Summary.build()
- *             .quantile(0.5, 0.05)   // Add 50th percentile (= median) with 5% tolerated error
- *             .quantile(0.9, 0.01)   // Add 90th percentile with 1% tolerated error
- *             .quantile(0.99, 0.001) // Add 99th percentile with 0.1% tolerated error
- *             .name("requests_size_bytes")
- *             .help("Request size in bytes.")
- *             .register();
- * }
+ * Summary requestLatency = Summary.build()
+ *     .name("requests_latency_seconds")
+ *     .help("Request latency in seconds.")
+ *     .quantile(0.5, 0.01)    // 0.5 quantile (median) with 0.01 allowed error
+ *     .quantile(0.95, 0.005)  // 0.95 quantile with 0.005 allowed error
+ *     // ...
+ *     .register();
  * </pre>
  *
- * The quantiles are calculated over a sliding window of time. There are two options to configure this time window:
+ * As an example, a 0.95 quantile of 120ms tells you that 95% of the calls were faster than 120ms, and 5% of the calls were slower than 120ms.
+ * <p>
+ * Tracking exact quantiles require a large amount of memory, because all observations need to be stored in a sorted list. Therefore, we allow an error to significantly reduce memory usage.
+ * <p>
+ * In the example, the allowed error of 0.005 means that you will not get the exact 0.95 quantile, but anything between the 0.945 quantile and the 0.955 quantile.
+ * <p>
+ * Experiments show that the {@link Summary} typically needs to keep less than 100 samples to provide that precision, even if you have hundreds of millions of observations.
+ * <p>
+ * There are a few special cases:
+ *
  * <ul>
- *   <li>maxAgeSeconds(long): Set the duration of the time window is, i.e. how long observations are kept before they are discarded.
- *       Default is 10 minutes.
- *   <li>ageBuckets(int): Set the number of buckets used to implement the sliding time window. If your time window is 10 minutes, and you have ageBuckets=5,
- *       buckets will be switched every 2 minutes. The value is a trade-off between resources (memory and cpu for maintaining the bucket)
- *       and how smooth the time window is moved. Default value is 5.
+ *   <li>You can set an allowed error of 0, but then the {@link Summary} will keep all observations in memory.</li>
+ *   <li>You can track the minimum value with {@code .quantile(0.0, 0.0)}.
+ *       This special case will not use additional memory even though the allowed error is 0.</li>
+ *   <li>You can track the maximum value with {@code .quantile(1.0, 0.0)}.
+ *       This special case will not use additional memory even though the allowed error is 0.</li>
  * </ul>
  *
- * See https://prometheus.io/docs/practices/histograms/ for more info on quantiles.
+ * Typically, you don't want to have a {@link Summary} representing the entire runtime of the application,
+ * but you want to look at a reasonable time interval. {@link Summary} metrics implement a configurable sliding
+ * time window:
+ *
+ * <pre>
+ * Summary requestLatency = Summary.build()
+ *     .name("requests_latency_seconds")
+ *     .help("Request latency in seconds.")
+ *     .maxAgeSeconds(10 * 60)
+ *     .ageBuckets(5)
+ *     // ...
+ *     .register();
+ * </pre>
+ *
+ * The default is a time window of 10 minutes and 5 age buckets, i.e. the time window is 10 minutes wide, and
+ * we slide it forward every 2 minutes.
  */
 public class Summary extends SimpleCollector<Summary.Child> implements Counter.Describable {
 
@@ -98,6 +119,10 @@ public static class Builder extends SimpleCollector.Builder<Builder, Summary> {
     private long maxAgeSeconds = TimeUnit.MINUTES.toSeconds(10);
     private int ageBuckets = 5;
 
+    /**
+     * The class JavaDoc for {@link Summary} has more information on {@link #quantile(double, double)}.
+     * @see Summary
+     */
     public Builder quantile(double quantile, double error) {
       if (quantile < 0.0 || quantile > 1.0) {
         throw new IllegalArgumentException("Quantile " + quantile + " invalid: Expected number between 0.0 and 1.0.");
@@ -109,6 +134,10 @@ public Builder quantile(double quantile, double error) {
       return this;
     }
 
+    /**
+     * The class JavaDoc for {@link Summary} has more information on {@link #maxAgeSeconds(long)} 
+     * @see Summary
+     */
     public Builder maxAgeSeconds(long maxAgeSeconds) {
       if (maxAgeSeconds <= 0) {
         throw new IllegalArgumentException("maxAgeSeconds cannot be " + maxAgeSeconds);
@@ -117,6 +146,10 @@ public Builder maxAgeSeconds(long maxAgeSeconds) {
       return this;
     }
 
+    /**
+     * The class JavaDoc for {@link Summary} has more information on {@link #ageBuckets(int)} 
+     * @see Summary
+     */
     public Builder ageBuckets(int ageBuckets) {
       if (ageBuckets <= 0) {
         throw new IllegalArgumentException("ageBuckets cannot be " + ageBuckets);
diff --git a/simpleclient/src/test/java/io/prometheus/client/CKMSQuantilesTest.java b/simpleclient/src/test/java/io/prometheus/client/CKMSQuantilesTest.java
new file mode 100644
index 000000000..f00371fec
--- /dev/null
+++ b/simpleclient/src/test/java/io/prometheus/client/CKMSQuantilesTest.java
@@ -0,0 +1,340 @@
+package io.prometheus.client;
+
+import io.prometheus.client.CKMSQuantiles.Quantile;
+import org.apache.commons.math3.distribution.NormalDistribution;
+import org.apache.commons.math3.random.JDKRandomGenerator;
+import org.apache.commons.math3.random.RandomGenerator;
+import org.junit.Test;
+
+import java.util.*;
+
+import static org.junit.Assert.*;
+
+public class CKMSQuantilesTest {
+
+    private final Quantile qMin = new Quantile(0.0, 0.00);
+    private final Quantile q50 = new Quantile(0.5, 0.01);
+    private final Quantile q95 = new Quantile(0.95, 0.005);
+    private final Quantile q99 = new Quantile(0.99, 0.001);
+    private final Quantile qMax = new Quantile(1.0, 0.00);
+
+    @Test
+    public void testGetOnEmptyValues() {
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, q95, q99);
+        assertTrue(Double.isNaN(ckms.get(q95.quantile)));
+    }
+
+    @Test
+    public void testGet() {
+        Random random = new Random(0);
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, q95, q99);
+        List<Double> input = shuffledValues(100, random);
+        for (double value : input) {
+            ckms.insert(value);
+        }
+        validateResults(ckms);
+    }
+
+    @Test
+    public void testBatchInsert() {
+        Random random = new Random(1);
+        testInsertBatch(1, 1, 100, random);
+        testInsertBatch(1, 10, 100, random);
+        testInsertBatch(2, 10, 100, random);
+        testInsertBatch(2, 110, 100, random); // compress never called, because compress interval > number of inserts
+        testInsertBatch(3, 10, 100, random);
+        testInsertBatch(10, 10, 100, random);
+        testInsertBatch(128, 128, 1, random);
+        testInsertBatch(128, 128, 1000, random);
+        testInsertBatch(128, 128, 10*1000, random);
+        testInsertBatch(128, 128, 100*1000, random);
+        testInsertBatch(128, 128, 1000*1000, random);
+    }
+
+    private void testInsertBatch(int batchSize, int compressInterval, int totalNumber, Random random) {
+        System.out.println("testInsertBatch(batchSize=" + batchSize + ", compressInterval=" + compressInterval + ", totalNumber=" + totalNumber + ")");
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, q95);
+        int insertsSinceCompress = 0;
+        List<Double> input = shuffledValues(totalNumber, random);
+        for (int i=0; i<input.size(); i+=batchSize) {
+            double[] batch = new double[batchSize];
+            int j;
+            for (j=0; j<batchSize && i+j < input.size(); j++) {
+                batch[j] = input.get(i+j);
+            }
+            Arrays.sort(batch, 0, j);
+            ckms.insertBatch(batch, j);
+            validateSamples(ckms); // after each insert the samples should still be valid
+            insertsSinceCompress += j;
+            if (insertsSinceCompress >= compressInterval) {
+                ckms.compress();
+                validateSamples(ckms); // after each compress the samples should still be valid
+                insertsSinceCompress=0;
+            }
+        }
+        validateResults(ckms);
+    }
+
+    @Test
+    public void testGetWithAMillionElements() {
+        Random random = new Random(2);
+        List<Double> input = shuffledValues(1000*1000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, q95, q99);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        assertTrue("sample size should be way below 1_000_000", ckms.samples.size() < 1000);
+    }
+
+    @Test
+    public void testMin() {
+        Random random = new Random(3);
+        List<Double> input = shuffledValues(1000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(qMin);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        ckms.compress();
+        assertEquals(2, ckms.samples.size());
+    }
+
+    @Test
+    public void testMax() {
+        Random random = new Random(4);
+        List<Double> input = shuffledValues(1000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(qMax);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        ckms.compress();
+        assertEquals(2, ckms.samples.size());
+    }
+
+    @Test
+    public void testMinMax() {
+        Random random = new Random(5);
+        List<Double> input = shuffledValues(1000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(qMin, qMax);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        ckms.compress();
+        assertEquals(2, ckms.samples.size());
+    }
+
+    @Test
+    public void testMinAndOthers() {
+        Random random = new Random(6);
+        List<Double> input = shuffledValues(1000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(q95, qMin);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        assertTrue(ckms.samples.size() < 200); // should be a lot less than input.size()
+    }
+
+    @Test
+    public void testMaxAndOthers() {
+        Random random = new Random(7);
+        List<Double> input = shuffledValues(10000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, q95, qMax);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        assertTrue(ckms.samples.size() < 200); // should be a lot less than input.size()
+    }
+
+    @Test
+    public void testMinMaxAndOthers() {
+        Random random = new Random(8);
+        List<Double> input = shuffledValues(10000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(qMin, q50, q95, q99, qMax);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        assertTrue(ckms.samples.size() < 200); // should be a lot less than input.size()
+    }
+
+    @Test
+    public void testExactQuantile() {
+        Random random = new Random(9);
+        List<Double> input = shuffledValues(10000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(new Quantile(0.95, 0));
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        // With epsilon == 0 we need to keep all inputs in samples.
+        assertEquals(input.size(), ckms.samples.size());
+    }
+
+    @Test
+    public void testExactAndOthers() {
+        Random random = new Random(10);
+        List<Double> input = shuffledValues(10000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(q50, new Quantile(0.95, 0), q99);
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        // With epsilon == 0 we need to keep all inputs in samples.
+        assertEquals(input.size(), ckms.samples.size());
+    }
+
+    @Test
+    public void testExactAndMin() {
+        Random random = new Random(11);
+        List<Double> input = shuffledValues(10000, random);
+        CKMSQuantiles ckms = new CKMSQuantiles(qMin, q50, new Quantile(0.95, 0));
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+        // With epsilon == 0 we need to keep all inputs in samples.
+        assertEquals(input.size(), ckms.samples.size());
+    }
+
+    @Test
+    public void testMaxEpsilon() {
+        Random random = new Random(12);
+        List<Double> input = shuffledValues(10000, random);
+        // epsilon == 1 basically gives you random results, but it should still not throw an exception.
+        CKMSQuantiles ckms = new CKMSQuantiles(new Quantile(0.95, 1));
+        for (double v : input) {
+            ckms.insert(v);
+        }
+        validateResults(ckms);
+    }
+
+    @Test
+    public void testGetGaussian() {
+        RandomGenerator rand = new JDKRandomGenerator();
+        rand.setSeed(0);
+
+        double mean = 0.0;
+        double stddev = 1.0;
+        NormalDistribution normalDistribution = new NormalDistribution(rand, mean, stddev, NormalDistribution.DEFAULT_INVERSE_ABSOLUTE_ACCURACY);
+
+        List<Quantile> quantiles = new ArrayList<Quantile>();
+        quantiles.add(new Quantile(0.10, 0.001));
+        quantiles.add(new Quantile(0.50, 0.01));
+        quantiles.add(new Quantile(0.90, 0.001));
+        quantiles.add(new Quantile(0.95, 0.001));
+        quantiles.add(new Quantile(0.99, 0.001));
+
+        CKMSQuantiles ckms = new CKMSQuantiles(quantiles.toArray(new Quantile[]{}));
+
+        final int elemCount = 1000*1000;
+        double[] shuffle = normalDistribution.sample(elemCount);
+
+        // insert a million samples
+        for (double v : shuffle) {
+            ckms.insert(v);
+        }
+
+        // give the actual values for the quantiles we test
+        double p10 = normalDistribution.inverseCumulativeProbability(0.1);
+        double p90 = normalDistribution.inverseCumulativeProbability(0.9);
+        double p95 = normalDistribution.inverseCumulativeProbability(0.95);
+        double p99 = normalDistribution.inverseCumulativeProbability(0.99);
+
+        //ε-approximate quantiles relaxes the requirement
+        //to finding an item with rank between (φ−ε)n and (φ+ε)n.
+        assertEquals(p10, ckms.get(0.1), errorBoundsNormalDistribution(0.1, 0.001, normalDistribution));
+        assertEquals(mean, ckms.get(0.5), errorBoundsNormalDistribution(0.5, 0.01, normalDistribution));
+        assertEquals(p90, ckms.get(0.9), errorBoundsNormalDistribution(0.9, 0.001, normalDistribution));
+        assertEquals(p95, ckms.get(0.95), errorBoundsNormalDistribution(0.95, 0.001, normalDistribution));
+        assertEquals(p99, ckms.get(0.99), errorBoundsNormalDistribution(0.99, 0.001, normalDistribution));
+
+        assertTrue("sample size should be below 1000", ckms.samples.size() < 1000);
+    }
+
+    double errorBoundsNormalDistribution(double p, double epsilon, NormalDistribution nd) {
+        //(φ+ε)n
+        double upperBound = nd.inverseCumulativeProbability(p + epsilon);
+        //(φ−ε)n
+        double lowerBound = nd.inverseCumulativeProbability(p - epsilon);
+        // subtract and divide by 2, assuming that the increase is linear in this small epsilon.
+        return Math.abs(upperBound - lowerBound) / 2;
+    }
+
+    @Test
+    public void testIllegalArgumentException() {
+        try {
+            new Quantile(-1, 0);
+        } catch (IllegalArgumentException e) {
+            assertEquals("Quantile must be between 0 and 1", e.getMessage());
+        } catch (Exception e) {
+            fail("Wrong exception thrown" + e);
+        }
+        try {
+            new Quantile(0.95, 2);
+        } catch (IllegalArgumentException e) {
+            assertEquals("Epsilon must be between 0 and 1", e.getMessage());
+        } catch (Exception e) {
+            fail("Wrong exception thrown" + e);
+        }
+    }
+
+    private List<Double> shuffledValues(int n, Random random) {
+        List<Double> result = new ArrayList<Double>(n);
+        for (int i=0; i<n; i++) {
+            result.add(i+1.0);
+        }
+        Collections.shuffle(result, random);
+        return result;
+    }
+
+    /**
+     * The following invariant must be true for each sample: g + delta <= f(r)
+     */
+    private void validateSamples(CKMSQuantiles ckms) {
+        double prev = -1.0;
+        int r = 0; // sum of all g's left of the current sample
+        for (CKMSQuantiles.Sample sample : ckms.samples) {
+            String msg = "invalid sample " + sample + ": count=" + ckms.n + " r=" + r + " f(r)=" + ckms.f(r);
+            assertTrue(msg, sample.g + sample.delta <= ckms.f(r));
+            assertTrue("Samples not ordered. Keep in mind that insertBatch() takes a sorted array as parameter.", prev <= sample.value);
+            prev = sample.value;
+            r += sample.g;
+        }
+        assertEquals("the sum of all g's must be the total number of observations", r, ckms.n);
+    }
+
+    /**
+     * The values that we insert in these tests are always the numbers from 1 to n, in random order.
+     * So we can trivially calculate the range of acceptable results for each quantile.
+     * We check if the value returned by get() is within the range of acceptable results.
+     */
+    private void validateResults(CKMSQuantiles ckms) {
+        for (Quantile q : ckms.quantiles) {
+            double actual = ckms.get(q.quantile);
+            double lowerBound, upperBound;
+            if (q.quantile == 0) {
+                lowerBound = 1;
+                upperBound = 1;
+            } else if (q.quantile == 1) {
+                lowerBound = ckms.n;
+                upperBound = ckms.n;
+            } else {
+                lowerBound = Math.floor(ckms.n * (q.quantile - 2 * q.epsilon));
+                upperBound = Math.ceil(ckms.n * (q.quantile + 2 * q.epsilon));
+            }
+            boolean ok = actual >= lowerBound && actual <= upperBound;
+            if (!ok) {
+                for (CKMSQuantiles.Sample sample : ckms.samples) {
+                    System.err.println(sample);
+                }
+            }
+            String errorMessage = q + ": " + actual + " not in [" + lowerBound + ", " + upperBound + "], n=" + ckms.n + ", " +  q.quantile + "*" + ckms.n + "=" + (q.quantile*ckms.n);
+            assertTrue(errorMessage, ok);
+        }
+    }
+}
\ No newline at end of file
diff --git a/simpleclient_bom/pom.xml b/simpleclient_bom/pom.xml
index c8bf490fb..d79c63d0b 100644
--- a/simpleclient_bom/pom.xml
+++ b/simpleclient_bom/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_bom</artifactId>
diff --git a/simpleclient_caffeine/pom.xml b/simpleclient_caffeine/pom.xml
index f273ec83b..90005fa7c 100644
--- a/simpleclient_caffeine/pom.xml
+++ b/simpleclient_caffeine/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_caffeine</artifactId>
@@ -36,12 +36,12 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>com.github.ben-manes.caffeine</groupId>
             <artifactId>caffeine</artifactId>
-            <version>2.7.0</version>
+            <version>2.9.3</version>
         </dependency>
         
 
@@ -55,13 +55,13 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
 
diff --git a/simpleclient_common/pom.xml b/simpleclient_common/pom.xml
index 6fdd64144..fac75ceef 100644
--- a/simpleclient_common/pom.xml
+++ b/simpleclient_common/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_common</artifactId>
@@ -36,7 +36,7 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <!-- Test Dependencies Follow -->
         <dependency>
diff --git a/simpleclient_common/src/test/java/io/prometheus/client/exporter/common/ExemplarTest.java b/simpleclient_common/src/test/java/io/prometheus/client/exporter/common/ExemplarTest.java
index 469446cda..2ab2821f9 100644
--- a/simpleclient_common/src/test/java/io/prometheus/client/exporter/common/ExemplarTest.java
+++ b/simpleclient_common/src/test/java/io/prometheus/client/exporter/common/ExemplarTest.java
@@ -310,15 +310,15 @@ public void testSummaryNoLabels() throws IOException {
         .help("help")
         .quantile(0.5, 0.01)
         .register(registry);
-    for (int i=1; i<=11; i++) { // median is 5
+    for (int i=1; i<=11; i++) { // median is 6
       noLabelsDefaultExemplar.observe(i);
     }
     // Summaries don't have Exemplars according to the OpenMetrics spec.
-    assertOpenMetrics100Format("no_labels{quantile=\"0.5\"} 5.0\n");
+    assertOpenMetrics100Format("no_labels{quantile=\"0.5\"} 6.0\n");
     assertOpenMetrics100Format("no_labels_count 11.0\n");
     assertOpenMetrics100Format("no_labels_sum 66.0\n");
 
-    assert004Format("no_labels{quantile=\"0.5\",} 5.0\n");
+    assert004Format("no_labels{quantile=\"0.5\",} 6.0\n");
     assert004Format("no_labels_count 11.0\n");
     assert004Format("no_labels_sum 66.0\n");
   }
@@ -331,15 +331,15 @@ public void testSummaryLabels() throws IOException {
         .labelNames("label")
         .quantile(0.5, 0.01)
         .register(registry);
-    for (int i=1; i<=11; i++) { // median is 5
+    for (int i=1; i<=11; i++) { // median is 6
       labelsNoExemplar.labels("test").observe(i);
     }
     // Summaries don't have Exemplars according to the OpenMetrics spec.
-    assertOpenMetrics100Format("labels{label=\"test\",quantile=\"0.5\"} 5.0\n");
+    assertOpenMetrics100Format("labels{label=\"test\",quantile=\"0.5\"} 6.0\n");
     assertOpenMetrics100Format("labels_count{label=\"test\"} 11.0\n");
     assertOpenMetrics100Format("labels_sum{label=\"test\"} 66.0\n");
 
-    assert004Format("labels{label=\"test\",quantile=\"0.5\",} 5.0\n");
+    assert004Format("labels{label=\"test\",quantile=\"0.5\",} 6.0\n");
     assert004Format("labels_count{label=\"test\",} 11.0\n");
     assert004Format("labels_sum{label=\"test\",} 66.0\n");
   }
diff --git a/simpleclient_dropwizard/pom.xml b/simpleclient_dropwizard/pom.xml
index 9993b45a8..b05def52f 100644
--- a/simpleclient_dropwizard/pom.xml
+++ b/simpleclient_dropwizard/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_dropwizard</artifactId>
@@ -34,12 +34,13 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.dropwizard.metrics</groupId>
             <artifactId>metrics-core</artifactId>
-            <version>3.1.2</version>
+            <version>4.2.8</version>
+            <scope>provided</scope>
         </dependency>
         <!-- Test Dependencies Follow -->
         <dependency>
@@ -51,7 +52,7 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.9.1</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
diff --git a/simpleclient_graphite_bridge/pom.xml b/simpleclient_graphite_bridge/pom.xml
index 4f28d5aca..a5858ed20 100644
--- a/simpleclient_graphite_bridge/pom.xml
+++ b/simpleclient_graphite_bridge/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_graphite_bridge</artifactId>
@@ -37,7 +37,7 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <!-- Test Dependencies Follow -->
         <dependency>
diff --git a/simpleclient_guava/pom.xml b/simpleclient_guava/pom.xml
index 75bde610e..e4d7be62b 100644
--- a/simpleclient_guava/pom.xml
+++ b/simpleclient_guava/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_guava</artifactId>
@@ -36,7 +36,7 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>com.google.guava</groupId>
@@ -55,13 +55,13 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
 
diff --git a/simpleclient_hibernate/pom.xml b/simpleclient_hibernate/pom.xml
index c4f4fd704..585b71eba 100644
--- a/simpleclient_hibernate/pom.xml
+++ b/simpleclient_hibernate/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_hibernate</artifactId>
@@ -37,14 +37,14 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
 
         <!-- We support Hibernate versions >= 4.2 -->
         <dependency>
             <groupId>org.hibernate</groupId>
             <artifactId>hibernate-core</artifactId>
-            <version>5.2.0.Final</version>
+            <version>5.6.5.Final</version>
             <scope>provided</scope>
         </dependency>
 
@@ -58,7 +58,7 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.18.0</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
 
diff --git a/simpleclient_hotspot/pom.xml b/simpleclient_hotspot/pom.xml
index 2e7543df1..d079df396 100644
--- a/simpleclient_hotspot/pom.xml
+++ b/simpleclient_hotspot/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_hotspot</artifactId>
@@ -36,14 +36,14 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         
         <!-- Test Dependencies Follow -->
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_servlet</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -62,7 +62,7 @@
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
             <artifactId>jetty-servlet</artifactId>
-            <version>8.1.7.v20120910</version>
+            <version>8.2.0.v20160908</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_httpserver/pom.xml b/simpleclient_httpserver/pom.xml
index 86fb104d2..76fa866d0 100644
--- a/simpleclient_httpserver/pom.xml
+++ b/simpleclient_httpserver/pom.xml
@@ -1,11 +1,23 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
 
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_httpserver</artifactId>
@@ -36,12 +48,12 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <!-- Test Dependencies Follow -->
         <dependency>
@@ -53,13 +65,13 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>javax.xml.bind</groupId>
             <artifactId>jaxb-api</artifactId>
-            <version>2.3.0</version>
+            <version>2.4.0-b180830.0359</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java b/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java
index f56bc8860..e930c4e3e 100644
--- a/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java
+++ b/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java
@@ -72,6 +72,9 @@ public static class HTTPMetricHandler implements HttpHandler {
         private final LocalByteArray response = new LocalByteArray();
         private final Supplier<Predicate<String>> sampleNameFilterSupplier;
         private final static String HEALTHY_RESPONSE = "Exporter is Healthy.";
+        private Integer metricRequests = 0;
+        private Integer healthRequests = 0;
+        private Integer reqCountRequests = 0;
 
         public HTTPMetricHandler(CollectorRegistry registry) {
             this(registry, null);
@@ -90,8 +93,14 @@ public void handle(HttpExchange t) throws IOException {
             response.reset();
             OutputStreamWriter osw = new OutputStreamWriter(response, Charset.forName("UTF-8"));
             if ("/-/healthy".equals(contextPath)) {
+                healthRequests++;
                 osw.write(HEALTHY_RESPONSE);
+            } else if("/-/req-count".equals(contextPath)) {
+                reqCountRequests++;
+                Integer totalReqs = metricRequests + healthRequests + reqCountRequests;
+                osw.write(totalReqs.toString());
             } else {
+                metricRequests++;
                 String contentType = TextFormat.chooseContentType(t.getRequestHeaders().getFirst("Accept"));
                 t.getResponseHeaders().set("Content-Type", contentType);
                 Predicate<String> filter = sampleNameFilterSupplier == null ? null : sampleNameFilterSupplier.get();
@@ -116,7 +125,9 @@ public void handle(HttpExchange t) throws IOException {
                 }
             } else {
                 long contentLength = response.size();
-                t.getResponseHeaders().set("Content-Length", String.valueOf(contentLength));
+                if (contentLength > 0) {
+                    t.getResponseHeaders().set("Content-Length", String.valueOf(contentLength));
+                }
                 if (t.getRequestMethod().equals("HEAD")) {
                     contentLength = -1;
                 }
@@ -132,11 +143,8 @@ protected static boolean shouldUseCompression(HttpExchange exchange) {
         if (encodingHeaders == null) return false;
 
         for (String encodingHeader : encodingHeaders) {
-            String[] encodings = encodingHeader.split(",");
-            for (String encoding : encodings) {
-                if (encoding.trim().equalsIgnoreCase("gzip")) {
-                    return true;
-                }
+            if (encodingHeader.equals("gzip")) {
+                return true;
             }
         }
         return false;
@@ -432,6 +440,10 @@ private HTTPServer(HttpServer httpServer, CollectorRegistry registry, boolean da
         if (authenticator != null) {
             mContext.setAuthenticator(authenticator);
         }
+        mContext = server.createContext("/-/req-count", mHandler);
+        if (authenticator != null) {
+            mContext.setAuthenticator(authenticator);
+        }
         executorService = Executors.newFixedThreadPool(5, NamedDaemonThreadFactory.defaultThreadFactory(daemon));
         server.setExecutor(executorService);
         start(daemon);
diff --git a/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpRequest.java b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpRequest.java
new file mode 100644
index 000000000..a08dcfeba
--- /dev/null
+++ b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpRequest.java
@@ -0,0 +1,302 @@
+package io.prometheus.client.exporter;
+
+import javax.net.ssl.HostnameVerifier;
+import javax.net.ssl.HttpsURLConnection;
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.TrustManager;
+import javax.xml.bind.DatatypeConverter;
+import java.io.*;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.net.URLConnection;
+import java.security.GeneralSecurityException;
+import java.security.KeyManagementException;
+import java.security.NoSuchAlgorithmException;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Scanner;
+import java.util.Set;
+import java.util.zip.GZIPInputStream;
+
+/**
+ * Class to perform HTTP testing
+ */
+public class HttpRequest {
+
+    enum METHOD { GET, HEAD }
+
+    private final Configuration configuration;
+
+    /**
+     * Constructor
+     *
+     * @param configuration configuration
+     */
+    private HttpRequest(Configuration configuration) {
+        this.configuration = configuration;
+    }
+
+    /**
+     * Method to execute an HTTP request
+     *
+     * @return HttpResponse
+     * @throws IOException
+     */
+    public HttpResponse execute() throws IOException {
+        if (configuration.url.toLowerCase().startsWith("https://") && (configuration.trustManagers != null)) {
+            try {
+                SSLContext sslContext = SSLContext.getInstance("SSL");
+                sslContext.init(null, configuration.trustManagers, new java.security.SecureRandom());
+                HttpsURLConnection.setDefaultSSLSocketFactory(sslContext.getSocketFactory());
+            } catch (GeneralSecurityException e) {
+                throw new IOException(e);
+            }
+
+            if (configuration.hostnameVerifier != null) {
+                HttpsURLConnection.setDefaultHostnameVerifier(configuration.hostnameVerifier);
+            }
+        }
+
+        URLConnection urlConnection = new URL(configuration.url).openConnection();
+        ((HttpURLConnection) urlConnection).setRequestMethod(configuration.method.toString());
+
+        Set<Map.Entry<String, List<String>>> entries = configuration.headers.entrySet();
+        for (Map.Entry<String, List<String>> entry : entries) {
+            for (String value : entry.getValue()) {
+                urlConnection.addRequestProperty(entry.getKey(), value);
+            }
+        }
+
+        urlConnection.setUseCaches(false);
+        urlConnection.setDoInput(true);
+        urlConnection.setDoOutput(true);
+        urlConnection.connect();
+
+        Scanner scanner = new Scanner(urlConnection.getInputStream(), "UTF-8").useDelimiter("\\A");
+
+        return new HttpResponse(
+                ((HttpURLConnection) urlConnection).getResponseCode(),
+                urlConnection.getHeaderFields(),
+                        urlConnection.getContentLength(), scanner.hasNext() ? scanner.next() : "");
+    }
+
+    /**
+     * Method to execute an HTTP request and decompresses it
+     *
+     * @return HttpResponse
+     * @throws IOException
+     */
+    public HttpResponse executeAndDecompress() throws IOException {
+        if (configuration.url.toLowerCase().startsWith("https://") && (configuration.trustManagers != null)) {
+            try {
+                SSLContext sslContext = SSLContext.getInstance("SSL");
+                sslContext.init(null, configuration.trustManagers, new java.security.SecureRandom());
+                HttpsURLConnection.setDefaultSSLSocketFactory(sslContext.getSocketFactory());
+            } catch (GeneralSecurityException e) {
+                throw new IOException(e);
+            }
+
+            if (configuration.hostnameVerifier != null) {
+                HttpsURLConnection.setDefaultHostnameVerifier(configuration.hostnameVerifier);
+            }
+        }
+
+        URLConnection urlConnection = new URL(configuration.url).openConnection();
+        ((HttpURLConnection) urlConnection).setRequestMethod(configuration.method.toString());
+
+        Set<Map.Entry<String, List<String>>> entries = configuration.headers.entrySet();
+        for (Map.Entry<String, List<String>> entry : entries) {
+            for (String value : entry.getValue()) {
+                urlConnection.addRequestProperty(entry.getKey(), value);
+            }
+        }
+
+        urlConnection.setUseCaches(false);
+        urlConnection.setDoInput(true);
+        urlConnection.setDoOutput(true);
+        urlConnection.connect();
+
+        InputStream stream = urlConnection.getInputStream();
+        String body = this.decompress(stream);
+
+        return new HttpResponse(
+                ((HttpURLConnection) urlConnection).getResponseCode(),
+                urlConnection.getHeaderFields(),
+                urlConnection.getContentLength(), body);
+    }
+
+    private String decompress(InputStream stream) throws IOException {
+        GZIPInputStream gis = new GZIPInputStream(stream);
+        BufferedReader br = new BufferedReader(new InputStreamReader(gis, "UTF-8"));
+        StringBuilder sb = new StringBuilder();
+        String line;
+        while((line = br.readLine()) != null) {
+            sb.append(line);
+        }
+        br.close();
+        gis.close();
+        return sb.toString();
+    }
+
+    /**
+     * Class to build an HttpRequest
+     */
+    static class Builder {
+
+        private final Configuration configuration;
+
+        /**
+         * Constructor
+         */
+        public Builder() {
+            configuration = new Configuration();
+        }
+
+        /**
+         * Method to set the HTTP request method
+         *
+         * @param method
+         * @return Builder
+         */
+        public Builder withMethod(METHOD method) {
+            configuration.method = method;
+            return this;
+        }
+
+        /**
+         * Method to set the HTTP request URL
+         *
+         * @param url
+         * @return Builder
+         */
+        public Builder withURL(String url) {
+            configuration.url = url;
+            return this;
+        }
+
+        /**
+         * Method to add an HTTP request header
+         *
+         * @param name
+         * @param value
+         * @return Builder
+         */
+        public Builder withHeader(String name, String value) {
+            configuration.addHeader(name, value);
+            return this;
+        }
+
+        /**
+         * Method to set the HTTP request "Authorization" header
+         *
+         * @param username
+         * @param password
+         * @return Builder
+         */
+        public Builder withAuthorization(String username, String password) {
+            configuration.setHeader("Authorization", encodeCredentials(username, password));
+            return this;
+        }
+
+        /**
+         * Method to set the HTTP request trust managers when using an SSL URL
+         *
+         * @param trustManagers
+         * @return Builder
+         */
+        public Builder withTrustManagers(TrustManager[] trustManagers) {
+            configuration.trustManagers = trustManagers;
+            return this;
+        }
+
+        /**
+         * Method to set the HTTP request hostname verifier when using an SSL URL
+         *
+         * @param hostnameVerifier
+         * @return Builder
+         */
+        public Builder withHostnameVerifier(HostnameVerifier hostnameVerifier) {
+            configuration.hostnameVerifier = hostnameVerifier;
+            return this;
+        }
+
+        /**
+         * Method to build the HttpRequest
+         *
+         * @return HttpRequest
+         */
+        public HttpRequest build() {
+            return new HttpRequest(configuration);
+        }
+    }
+
+    /**
+     * Class used for Builder configuration
+     */
+    private static class Configuration {
+
+        public METHOD method;
+        public String url;
+        public Map<String, List<String>> headers;
+        public TrustManager[] trustManagers;
+        public HostnameVerifier hostnameVerifier;
+
+        /**
+         * Constructor
+         */
+        Configuration() {
+            method = METHOD.GET;
+            headers = new HashMap<String, List<String>>();
+        }
+
+        /**
+         * Method to add (append) an HTTP request header
+         *
+         * @param name
+         * @param value
+         * @return Configuration
+         */
+        void addHeader(String name, String value) {
+            name = name.toLowerCase();
+            List<String> values = headers.get(name);
+            if (values == null) {
+                values = new LinkedList<String>();
+                headers.put(name, values);
+            }
+
+            values.add(value);
+        }
+
+        /**
+         * Method to set (overwrite) an HTTP request header, removing all previous header values
+         *
+         * @param name
+         * @param value
+         * @return Configuration
+         */
+        void setHeader(String name, String value) {
+            List<String> values = new LinkedList<String>();
+            values.add(value);
+            headers.put(name, values);
+        }
+    }
+
+    /**
+     * Method to encode "Authorization" credentials
+     *
+     * @param username
+     * @param password
+     * @return String
+     */
+    private final static String encodeCredentials(String username, String password) {
+        // Per RFC4648 table 2. We support Java 6, and java.util.Base64 was only added in Java 8,
+        try {
+            byte[] credentialsBytes = (username + ":" + password).getBytes("UTF-8");
+            return "Basic " + DatatypeConverter.printBase64Binary(credentialsBytes);
+        } catch (UnsupportedEncodingException e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
+}
diff --git a/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpResponse.java b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpResponse.java
new file mode 100644
index 000000000..9ad49be41
--- /dev/null
+++ b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/HttpResponse.java
@@ -0,0 +1,109 @@
+package io.prometheus.client.exporter;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Class to perform HTTP testing
+ */
+class HttpResponse {
+
+    private int responseCode;
+    private Map<String, List<String>> headers;
+    private long contentLength = -1;
+    private String body;
+
+    /**
+     * Constructor
+     *
+     * @param responseCode
+     * @param headers
+     * @param contentLength
+     * @param body
+     */
+    HttpResponse(int responseCode, Map<String, List<String>> headers, long contentLength, String body) throws IOException {
+        this.responseCode = responseCode;
+        this.body = body;
+        this.contentLength = contentLength;
+        this.headers = new HashMap<String, List<String>>();
+
+        Set<Map.Entry<String, List<String>>> headerSet = headers.entrySet();
+        for (String header : headers.keySet()) {
+            if (header != null) {
+                List<String> values = headers.get(header);
+                this.headers.put(header.toLowerCase(), values);
+            }
+        }
+
+        if (getHeader("content-length") != null && getHeader("transfer-encoding") != null) {
+            throw new IOException("Invalid HTTP response, should only contain Connect-Length or Transfer-Encoding");
+        }
+    }
+
+    /**
+     * Method to get the HTTP response code
+     *
+     * @return int
+     */
+    public int getResponseCode() {
+        return this.responseCode;
+    }
+
+    /**
+     * Method to get a list of HTTP response headers values
+     *
+     * @param name
+     * @return List<String>
+     */
+    public List<String> getHeaderList(String name) {
+        return headers.get(name.toLowerCase());
+    }
+
+    /**
+     * Method to get the first HTTP response header value
+     *
+     * @param name
+     * @return String
+     */
+    public String getHeader(String name) {
+        String value = null;
+
+        List<String> valueList = getHeaderList(name);
+        if (valueList != null && (valueList.size() >= 0)) {
+            value = valueList.get(0);
+        }
+
+        return value;
+    }
+
+    /**
+     * Method to get the first HTTP response header value as a Long.
+     * Returns null of the header doesn't exist
+     *
+     * @param name
+     * @return Long
+     */
+    public Long getHeaderAsLong(String name) {
+        String value = getHeader(name);
+        if (value != null) {
+            try {
+                return Long.valueOf(value);
+            } catch (Exception e) {
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Method to get the HTTP response body
+     *
+     * @return String
+     */
+    public String getBody() {
+        return body;
+    }
+}
diff --git a/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/TestHTTPServer.java b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/TestHTTPServer.java
index bb8f7fa13..11c15703d 100644
--- a/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/TestHTTPServer.java
+++ b/simpleclient_httpserver/src/test/java/io/prometheus/client/exporter/TestHTTPServer.java
@@ -5,30 +5,14 @@
 import com.sun.net.httpserver.HttpServer;
 import com.sun.net.httpserver.HttpsConfigurator;
 import com.sun.net.httpserver.HttpsParameters;
-import io.prometheus.client.Gauge;
 import io.prometheus.client.CollectorRegistry;
-
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.IOException;
-import java.io.UnsupportedEncodingException;
-import java.net.HttpURLConnection;
-import java.net.InetSocketAddress;
-import java.net.URL;
-import java.net.URLConnection;
-import java.security.GeneralSecurityException;
-import java.security.KeyStore;
-import java.security.cert.X509Certificate;
-import java.util.Scanner;;
-import java.util.zip.GZIPInputStream;
-
+import io.prometheus.client.Gauge;
 import io.prometheus.client.SampleNameFilter;
 import org.junit.Assert;
 import org.junit.Before;
-import org.junit.Test;;
+import org.junit.Test;
 
 import javax.net.ssl.HostnameVerifier;
-import javax.net.ssl.HttpsURLConnection;
 import javax.net.ssl.KeyManagerFactory;
 import javax.net.ssl.SSLContext;
 import javax.net.ssl.SSLEngine;
@@ -38,6 +22,19 @@
 import javax.net.ssl.TrustManagerFactory;
 import javax.net.ssl.X509TrustManager;
 import javax.xml.bind.DatatypeConverter;
+import java.io.*;
+import java.net.InetSocketAddress;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.security.GeneralSecurityException;
+import java.security.KeyStore;
+import java.security.cert.X509Certificate;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+import java.util.zip.GZIPInputStream;
+import java.util.zip.GZIPOutputStream;
 
 import static org.assertj.core.api.Java6Assertions.assertThat;
 
@@ -66,45 +63,45 @@ public class TestHTTPServer {
     HTTPS_CONFIGURATOR = createHttpsConfigurator(SSL_CONTEXT);
   }
 
-  private final static TrustManager[] TRUST_MANAGERS = new TrustManager[]{
+  /**
+   * TrustManager[] that trusts all certificates
+   */
+  private final static TrustManager[] TRUST_ALL_CERTS_TRUST_MANAGERS = new TrustManager[]{
           new X509TrustManager() {
-            public java.security.cert.X509Certificate[] getAcceptedIssuers() {
+            public X509Certificate[] getAcceptedIssuers() {
               return new X509Certificate[0];
             }
 
-            public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType) {
+            public void checkClientTrusted(X509Certificate[] certs, String authType) {
             }
 
-            public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType) {
+            public void checkServerTrusted(X509Certificate[] certs, String authType) {
             }
           }
   };
 
-  private final static HostnameVerifier HOSTNAME_VERIFIER = new HostnameVerifier() {
+  /**
+   * HostnameVerifier that accepts any hostname
+   */
+  private final static HostnameVerifier TRUST_ALL_HOSTS_HOSTNAME_VERIFIER = new HostnameVerifier() {
     @Override
     public boolean verify(String hostname, SSLSession session) {
       return true;
     }
   };
 
-  final static Authenticator createAuthenticator(String realm, final String validUsername, final String validPassword) {
-    return new BasicAuthenticator(realm) {
-      @Override
-      public boolean checkCredentials(String username, String password) {
-        return validUsername.equals(username) && validPassword.equals(password);
-      }
-    };
+  HttpRequest.Builder createHttpRequestBuilder(HTTPServer httpServer, String urlPath) {
+    return new HttpRequest.Builder().withURL("http://localhost:" + httpServer.getPort() + urlPath);
   }
 
-  class Response {
-
-    public long contentLength;
-    public String body;
+  HttpRequest.Builder createHttpRequestBuilderWithSSL(HTTPServer httpServer, String urlPath) {
+    return new HttpRequest.Builder().withURL("https://localhost:" + httpServer.getPort() + urlPath)
+            .withTrustManagers(TRUST_ALL_CERTS_TRUST_MANAGERS)
+            .withHostnameVerifier(TRUST_ALL_HOSTS_HOSTNAME_VERIFIER);
+  }
 
-    public Response(long contentLength, String body) {
-      this.contentLength = contentLength;
-      this.body = body;
-    }
+  HttpRequest.Builder createHttpRequestBuilder(HttpServer httpServer, String urlPath) {
+    return new HttpRequest.Builder().withURL("http://localhost:" + httpServer.getAddress().getPort() + urlPath);
   }
 
   @Before
@@ -115,316 +112,287 @@ public void init() throws IOException {
     Gauge.build("c", "a help").register(registry);
   }
 
-  Response request(String requestMethod, HTTPServer s, String context, String suffix) throws IOException {
-    String url = "http://localhost:" + s.server.getAddress().getPort() + context + suffix;
-    URLConnection connection = new URL(url).openConnection();
-    ((HttpURLConnection)connection).setRequestMethod(requestMethod);
-    connection.setDoOutput(true);
-    connection.connect();
-    Scanner scanner = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
-    return new Response(connection.getContentLength(), scanner.hasNext() ? scanner.next() : "");
-  }
-
-  Response request(HTTPServer s, String context, String suffix) throws IOException {
-    return request("GET", s, context, suffix);
-  }
-
-  Response request(HTTPServer s, String suffix) throws IOException {
-    return request(s, "/metrics", suffix);
-  }
-
-  Response requestWithCompression(HTTPServer s, String suffix) throws IOException {
-    return requestWithCompression(s, "/metrics", suffix);
-  }
-
-  Response requestWithCompression(HTTPServer s, String context, String suffix) throws IOException {
-    String url = "http://localhost:" + s.server.getAddress().getPort() + context + suffix;
-    URLConnection connection = new URL(url).openConnection();
-    connection.setDoOutput(true);
-    connection.setDoInput(true);
-    connection.setRequestProperty("Accept-Encoding", "gzip, deflate");
-    connection.connect();
-    GZIPInputStream gzs = new GZIPInputStream(connection.getInputStream());
-    Scanner scanner = new Scanner(gzs).useDelimiter("\\A");
-    return new Response(connection.getContentLength(), scanner.hasNext() ? scanner.next() : "");
-  }
-
-  Response requestWithAccept(HTTPServer s, String accept) throws IOException {
-    String url = "http://localhost:" + s.server.getAddress().getPort();
-    URLConnection connection = new URL(url).openConnection();
-    connection.setDoOutput(true);
-    connection.setDoInput(true);
-    connection.setRequestProperty("Accept", accept);
-    Scanner scanner = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
-    return new Response(connection.getContentLength(), scanner.hasNext() ? scanner.next() : "");
-  }
-
-  Response requestWithCredentials(HTTPServer httpServer, String context, String suffix, String username, String password) throws IOException {
-    String url = "http://localhost:" + httpServer.server.getAddress().getPort() + context + suffix;
-    URLConnection connection = new URL(url).openConnection();
-    connection.setDoOutput(true);
-    if (username != null && password != null) {
-      connection.setRequestProperty("Authorization", encodeCredentials(username, password));
-    }
-    connection.connect();
-    Scanner s = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
-    return new Response(connection.getContentLength(), s.hasNext() ? s.next() : "");
-  }
-
-  Response requestWithSSL(String requestMethod, String username, String password, HTTPServer s, String context, String suffix) throws GeneralSecurityException, IOException {
-    String url = "https://localhost:" + s.server.getAddress().getPort() + context + suffix;
-
-    SSLContext sc = SSLContext.getInstance("SSL");
-    sc.init(null, TRUST_MANAGERS, new java.security.SecureRandom());
-    HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
-    HttpsURLConnection.setDefaultHostnameVerifier(HOSTNAME_VERIFIER);
-
-    URLConnection connection = new URL(url).openConnection();
-    ((HttpURLConnection)connection).setRequestMethod(requestMethod);
-
-    if (username != null && password != null) {
-      connection.setRequestProperty("Authorization", encodeCredentials(username, password));
-    }
-
-    connection.setDoOutput(true);
-    connection.connect();
-    Scanner scanner = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
-    return new Response(connection.getContentLength(), scanner.hasNext() ? scanner.next() : "");
-  }
-
-  Response request(HttpServer httpServer, String context, String suffix) throws IOException {
-    String url = "http://localhost:" + httpServer.getAddress().getPort() + context + suffix;
-    URLConnection connection = new URL(url).openConnection();
-    connection.setDoOutput(true);
-    connection.connect();
-    Scanner s = new Scanner(connection.getInputStream(), "UTF-8").useDelimiter("\\A");
-    return new Response(connection.getContentLength(), s.hasNext() ? s.next() : "");
-  }
-
-  String encodeCredentials(String username, String password) {
-    // Per RFC4648 table 2. We support Java 6, and java.util.Base64 was only added in Java 8,
-    try {
-      byte[] credentialsBytes = (username + ":" + password).getBytes("UTF-8");
-      return "Basic " +  DatatypeConverter.printBase64Binary(credentialsBytes);
-    } catch (UnsupportedEncodingException e) {
-      throw new IllegalArgumentException(e);
-    }
-  }
-
   @Test(expected = IllegalArgumentException.class)
   public void testRefuseUsingUnbound() throws IOException {
     CollectorRegistry registry = new CollectorRegistry();
-    HTTPServer s = new HTTPServer(HttpServer.create(), registry, true);
-    s.close();
+    HTTPServer httpServer = new HTTPServer(HttpServer.create(), registry, true);
+    httpServer.close();
   }
 
   @Test
   public void testSimpleRequest() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).contains("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).contains("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testBadParams() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "?x").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).contains("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics?x").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).contains("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testSingleName() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "?name[]=a").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).doesNotContain("b 0.0");
-      assertThat(response).doesNotContain("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics?name[]=a").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).doesNotContain("b 0.0");
+      assertThat(body).doesNotContain("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testMultiName() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "?name[]=a&name[]=b").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).doesNotContain("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).doesNotContain("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testSampleNameFilter() throws IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
+            .withRegistry(registry)
+            .withSampleNameFilter(new SampleNameFilter.Builder()
+                    .nameMustNotStartWith("a")
+                    .build())
+            .build();
+
+    try {
+      String body = createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b").build().execute().getBody();
+      assertThat(body).doesNotContain("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).doesNotContain("c 0.0");
+    } finally {
+      httpServer.close();
+    }
+  }
+
+  @Test
+  public void testSampleNameFilterEmptyBody() throws IOException {
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withSampleNameFilter(new SampleNameFilter.Builder()
                     .nameMustNotStartWith("a")
+                    .nameMustNotStartWith("b")
                     .build())
             .build();
+
     try {
-      String response = request(s, "?name[]=a&name[]=b").body;
-      assertThat(response).doesNotContain("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).doesNotContain("c 0.0");
+      HttpResponse httpResponse = createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b").build().execute();
+      assertThat(httpResponse.getBody()).isEmpty();
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testDecoding() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "?n%61me[]=%61").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).doesNotContain("b 0.0");
-      assertThat(response).doesNotContain("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics?n%61me[]=%61").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).doesNotContain("b 0.0");
+      assertThat(body).doesNotContain("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testGzipCompression() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = requestWithCompression(s, "").body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).contains("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics")
+              .withHeader("Accept-Encoding", "gzip")
+              .build().executeAndDecompress().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).contains("c 0.0");
+
+      body = createHttpRequestBuilder(httpServer, "/metrics")
+              .withHeader("Accept-Encoding", "gzip")
+              .build().execute().getBody();
+      assertThat(body).doesNotContain("a 0.0");
+      assertThat(body).doesNotContain("b 0.0");
+      assertThat(body).doesNotContain("c 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testOpenMetrics() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = requestWithAccept(s, "application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1").body;
-      assertThat(response).contains("# EOF");
+      String body = createHttpRequestBuilder(httpServer, "/metrics")
+              .withHeader("Accept", "application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1")
+              .build().execute().getBody();
+      assertThat(body).contains("# EOF");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testHealth() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = request(s, "/-/healthy", "").body;
-      assertThat(response).contains("Exporter is Healthy");
+      String body = createHttpRequestBuilder(httpServer, "/-/healthy").build().execute().getBody();
+      assertThat(body).contains("Exporter is Healthy");
     } finally {
-      s.close();
+      httpServer.close();
+    }
+  }
+
+  @Test
+  public void testTotalRequests() throws IOException {
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
+    try {
+      String body = createHttpRequestBuilder(httpServer, "/-/req-count").build().execute().getBody();
+      assertThat(body).contains("1");
+      String body2 = createHttpRequestBuilder(httpServer, "/-/req-count").build().execute().getBody();
+      assertThat(body2).contains("2");
+    } finally {
+      httpServer.close();
     }
   }
 
   @Test
   public void testHealthGzipCompression() throws IOException {
-    HTTPServer s = new HTTPServer(new InetSocketAddress(0), registry);
+    HTTPServer httpServer = new HTTPServer(new InetSocketAddress(0), registry);
+
     try {
-      String response = requestWithCompression(s, "/-/healthy", "").body;
-      assertThat(response).contains("Exporter is Healthy");
+      String body = createHttpRequestBuilder(httpServer, "/-/healthy")
+              .withHeader("Accept", "gzip")
+              .withHeader("Accept", "deflate")
+              .build().execute().getBody();
+      assertThat(body).contains("Exporter is Healthy");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testBasicAuthSuccess() throws IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
+
     try {
-      String response = requestWithCredentials(s, "/metrics","?name[]=a&name[]=b", "user", "secret").body;
-      assertThat(response).contains("a 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b")
+              .withAuthorization("user", "secret")
+              .build().execute().getBody();
+      assertThat(body).contains("a 0.0");
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testBasicAuthCredentialsMissing() throws IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
+
     try {
-      request(s, "/metrics", "?name[]=a&name[]=b");
+      createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b").build().execute().getBody();
       Assert.fail("expected IOException with HTTP 401");
     } catch (IOException e) {
       Assert.assertTrue(e.getMessage().contains("401"));
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testBasicAuthWrongCredentials() throws IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
-            .withAuthenticator(createAuthenticator("/", "user", "wrong"))
+            .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
+
     try {
-      request(s, "/metrics", "?name[]=a&name[]=b");
+      createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b")
+              .withAuthorization("user", "wrong")
+              .build().execute().getBody();
       Assert.fail("expected IOException with HTTP 401");
     } catch (IOException e) {
       Assert.assertTrue(e.getMessage().contains("401"));
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testHEADRequest() throws IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .build();
-    try {
-      Response response = request("HEAD", s, "/metrics", "?name[]=a&name[]=b");
 
-      Assert.assertNotNull(response);
-      Assert.assertTrue(response.contentLength == 74);
-      Assert.assertTrue("".equals(response.body));
+    try {
+      HttpResponse httpResponse = createHttpRequestBuilder(httpServer, "/metrics?name[]=a&name[]=b")
+              .withMethod(HttpRequest.METHOD.HEAD)
+              .build().execute();
+      Assert.assertNotNull(httpResponse);
+      Assert.assertNotNull(httpResponse.getHeaderAsLong("content-length"));
+      Assert.assertTrue(httpResponse.getHeaderAsLong("content-length") == 74);
+      assertThat(httpResponse.getBody()).isEmpty();
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testHEADRequestWithSSL() throws GeneralSecurityException, IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withHttpsConfigurator(HTTPS_CONFIGURATOR)
             .build();
 
     try {
-      Response response = requestWithSSL(
-              "HEAD", null, null, s, "/metrics", "?name[]=a&name[]=b");
-
-      Assert.assertNotNull(response);
-      Assert.assertTrue(response.contentLength == 74);
-      Assert.assertTrue("".equals(response.body));
+      HttpResponse httpResponse = createHttpRequestBuilderWithSSL(httpServer, "/metrics?name[]=a&name[]=b")
+              .withMethod(HttpRequest.METHOD.HEAD)
+              .build().execute();
+      Assert.assertNotNull(httpResponse);
+      Assert.assertNotNull(httpResponse.getHeaderAsLong("content-length"));
+      Assert.assertTrue(httpResponse.getHeaderAsLong("content-length") == 74);
+      assertThat(httpResponse.getBody()).isEmpty();
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
@@ -436,10 +404,10 @@ public void testSimpleRequestHttpServerWithHTTPMetricHandler() throws IOExceptio
     httpServer.start();
 
     try {
-      String response = request(httpServer, "/metrics", null).body;
-      assertThat(response).contains("a 0.0");
-      assertThat(response).contains("b 0.0");
-      assertThat(response).contains("c 0.0");
+      String body = createHttpRequestBuilder(httpServer, "/metrics").build().execute().getBody();
+      assertThat(body).contains("a 0.0");
+      assertThat(body).contains("b 0.0");
+      assertThat(body).contains("c 0.0");
     } finally {
       httpServer.stop(0);
     }
@@ -447,59 +415,84 @@ public void testSimpleRequestHttpServerWithHTTPMetricHandler() throws IOExceptio
 
   @Test
   public void testHEADRequestWithSSLAndBasicAuthSuccess() throws GeneralSecurityException, IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withHttpsConfigurator(HTTPS_CONFIGURATOR)
             .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
 
     try {
-      Response response = requestWithSSL(
-              "HEAD", "user", "secret", s, "/metrics", "?name[]=a&name[]=b");
-
-      Assert.assertNotNull(response);
-      Assert.assertTrue(response.contentLength == 74);
-      Assert.assertTrue("".equals(response.body));
+      HttpResponse httpResponse = createHttpRequestBuilderWithSSL(httpServer, "/metrics?name[]=a&name[]=b")
+              .withMethod(HttpRequest.METHOD.HEAD)
+              .withAuthorization("user", "secret")
+              .build().execute();
+      Assert.assertNotNull(httpResponse);
+      Assert.assertNotNull(httpResponse.getHeaderAsLong("content-length"));
+      Assert.assertTrue(httpResponse.getHeaderAsLong("content-length") == 74);
+      assertThat(httpResponse.getBody()).isEmpty();
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testHEADRequestWithSSLAndBasicAuthCredentialsMissing() throws GeneralSecurityException, IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withHttpsConfigurator(HTTPS_CONFIGURATOR)
             .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
 
     try {
-      Response response = requestWithSSL("HEAD", null, null, s, "/metrics", "?name[]=a&name[]=b");
+      createHttpRequestBuilderWithSSL(httpServer, "/metrics?name[]=a&name[]=b")
+              .withMethod(HttpRequest.METHOD.HEAD)
+              .build().execute();
       Assert.fail("expected IOException with HTTP 401");
     } catch (IOException e) {
       Assert.assertTrue(e.getMessage().contains("401"));
     } finally {
-      s.close();
+      httpServer.close();
     }
   }
 
   @Test
   public void testHEADRequestWithSSLAndBasicAuthWrongCredentials() throws GeneralSecurityException, IOException {
-    HTTPServer s = new HTTPServer.Builder()
+    HTTPServer httpServer = new HTTPServer.Builder()
             .withRegistry(registry)
             .withHttpsConfigurator(HTTPS_CONFIGURATOR)
             .withAuthenticator(createAuthenticator("/", "user", "secret"))
             .build();
 
     try {
-      Response response = requestWithSSL("HEAD", "user", "wrong", s, "/metrics", "?name[]=a&name[]=b");
+      createHttpRequestBuilderWithSSL(httpServer, "/metrics?name[]=a&name[]=b")
+              .withMethod(HttpRequest.METHOD.HEAD)
+              .withAuthorization("user", "wrong")
+              .build().execute();
       Assert.fail("expected IOException with HTTP 401");
     } catch (IOException e) {
       Assert.assertTrue(e.getMessage().contains("401"));
     } finally {
-      s.close();
+      httpServer.close();
+    }
+  }
+
+  /**
+   * Encodes authorization credentials
+   *
+   * @param username
+   * @param password
+   * @return String
+   */
+  private final static String encodeCredentials(String username, String password) {
+    // Per RFC4648 table 2. We support Java 6, and java.util.Base64 was only added in Java 8,
+    try {
+      byte[] credentialsBytes = (username + ":" + password).getBytes("UTF-8");
+      return "Basic " +  DatatypeConverter.printBase64Binary(credentialsBytes);
+    } catch (UnsupportedEncodingException e) {
+      throw new IllegalArgumentException(e);
     }
   }
+
   /**
    * Create an SSLContext
    *
@@ -511,7 +504,7 @@ public void testHEADRequestWithSSLAndBasicAuthWrongCredentials() throws GeneralS
    * @throws GeneralSecurityException
    * @throws IOException
    */
-  public static SSLContext createSSLContext(String sslContextType, String keyStoreType, String keyStorePath, String keyStorePassword)
+  private final static SSLContext createSSLContext(String sslContextType, String keyStoreType, String keyStorePath, String keyStorePassword)
           throws GeneralSecurityException, IOException {
     SSLContext sslContext = null;
     FileInputStream fileInputStream = null;
@@ -550,7 +543,25 @@ public static SSLContext createSSLContext(String sslContextType, String keyStore
   }
 
   /**
+   * Creates an Authenticator
    *
+   * @param realm
+   * @param validUsername
+   * @param validPassword
+   * @return Authenticator
+   */
+  private final static Authenticator createAuthenticator(String realm, final String validUsername, final String validPassword) {
+    return new BasicAuthenticator(realm) {
+      @Override
+      public boolean checkCredentials(String username, String password) {
+        return validUsername.equals(username) && validPassword.equals(password);
+      }
+    };
+  }
+
+  /**
+   * Creates an HttpsConfiguration
+   * 
    * @param sslContext
    * @return HttpsConfigurator
    */
diff --git a/simpleclient_jetty/pom.xml b/simpleclient_jetty/pom.xml
index abf8cc29b..4ccae9591 100644
--- a/simpleclient_jetty/pom.xml
+++ b/simpleclient_jetty/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_jetty</artifactId>
@@ -38,7 +38,7 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
@@ -60,7 +60,7 @@
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest-all</artifactId>
-            <version>1.1</version>
+            <version>1.3</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_jetty/src/main/java/io/prometheus/client/jetty/JettyStatisticsCollector.java b/simpleclient_jetty/src/main/java/io/prometheus/client/jetty/JettyStatisticsCollector.java
index 8907ba151..7dddb00aa 100644
--- a/simpleclient_jetty/src/main/java/io/prometheus/client/jetty/JettyStatisticsCollector.java
+++ b/simpleclient_jetty/src/main/java/io/prometheus/client/jetty/JettyStatisticsCollector.java
@@ -9,8 +9,7 @@
 
 /**
  * Collect metrics from jetty's org.eclipse.jetty.server.handler.StatisticsHandler.
- * <p>
- * <pre>{@code
+ * <pre>
  * Server server = new Server(8080);
  *
  * ServletContextHandler context = new ServletContextHandler();
@@ -29,7 +28,7 @@
  * server.setHandler(handlers);
  *
  * server.start();
- * }</pre>
+ * </pre>
  */
 public class JettyStatisticsCollector extends Collector {
   private final StatisticsHandler statisticsHandler;
diff --git a/simpleclient_jetty_jdk8/pom.xml b/simpleclient_jetty_jdk8/pom.xml
index c9a1313e3..310d2d198 100644
--- a/simpleclient_jetty_jdk8/pom.xml
+++ b/simpleclient_jetty_jdk8/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_jetty_jdk8</artifactId>
@@ -47,7 +47,7 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
@@ -69,7 +69,7 @@
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest-all</artifactId>
-            <version>1.1</version>
+            <version>1.3</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_log4j/pom.xml b/simpleclient_log4j/pom.xml
index eda703aa7..dfaec19d4 100644
--- a/simpleclient_log4j/pom.xml
+++ b/simpleclient_log4j/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_log4j</artifactId>
@@ -36,14 +36,20 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
-            <groupId>log4j</groupId>
-            <artifactId>log4j</artifactId>
-            <version>1.2.17</version>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-core</artifactId>
+            <version>2.17.1</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.logging.log4j</groupId>
+            <artifactId>log4j-1.2-api</artifactId>
+            <version>2.17.1</version>
+            <scope>provided</scope>
         </dependency>
-        
 
         <dependency>
             <groupId>junit</groupId>
@@ -55,7 +61,7 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_log4j2/pom.xml b/simpleclient_log4j2/pom.xml
index 4d2e64dab..1006522c8 100644
--- a/simpleclient_log4j2/pom.xml
+++ b/simpleclient_log4j2/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_log4j2</artifactId>
@@ -36,12 +36,12 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-core</artifactId>
-            <version>2.17.0</version>
+            <version>2.17.1</version>
             <scope>provided</scope>
         </dependency>
 
@@ -55,7 +55,7 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_logback/pom.xml b/simpleclient_logback/pom.xml
index c245328a7..6642ec681 100644
--- a/simpleclient_logback/pom.xml
+++ b/simpleclient_logback/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_logback</artifactId>
@@ -36,12 +36,12 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-classic</artifactId>
-            <version>1.2.0</version>
+            <version>1.2.10</version>
         </dependency>
         
 
@@ -55,7 +55,7 @@
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_pushgateway/pom.xml b/simpleclient_pushgateway/pom.xml
index ba10fb802..4971eb0ab 100644
--- a/simpleclient_pushgateway/pom.xml
+++ b/simpleclient_pushgateway/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_pushgateway</artifactId>
@@ -37,17 +37,17 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>javax.xml.bind</groupId>
             <artifactId>jaxb-api</artifactId>
-            <version>2.3.0</version>
+            <version>2.4.0-b180830.0359</version>
             <scope>provided</scope>
         </dependency>
         <!-- Test Dependencies Follow -->
diff --git a/simpleclient_servlet/pom.xml b/simpleclient_servlet/pom.xml
index 8deb19ac3..9aab58f58 100644
--- a/simpleclient_servlet/pom.xml
+++ b/simpleclient_servlet/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_servlet</artifactId>
@@ -40,22 +40,22 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_servlet_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>javax.servlet-api</artifactId>
-            <version>3.0.1</version>
+            <version>3.1.0</version>
             <scope>provided</scope>
         </dependency>
         <!-- Test Dependencies Follow -->
@@ -68,19 +68,19 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
             <artifactId>jetty-servlet</artifactId>
-            <version>8.1.7.v20120910</version>
+            <version>8.2.0.v20160908</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_servlet/src/main/java/io/prometheus/client/exporter/MetricsServlet.java b/simpleclient_servlet/src/main/java/io/prometheus/client/exporter/MetricsServlet.java
index 76a6d5cee..3cd6af877 100644
--- a/simpleclient_servlet/src/main/java/io/prometheus/client/exporter/MetricsServlet.java
+++ b/simpleclient_servlet/src/main/java/io/prometheus/client/exporter/MetricsServlet.java
@@ -41,6 +41,7 @@ public MetricsServlet(CollectorRegistry registry, Predicate<String> sampleNameFi
   @Override
   public void init(ServletConfig servletConfig) throws ServletException {
     try {
+      super.init(servletConfig);
       exporter.init(Adapter.wrap(servletConfig));
     } catch (ServletConfigurationException e) {
       throw new ServletException(e);
diff --git a/simpleclient_servlet_common/pom.xml b/simpleclient_servlet_common/pom.xml
index debb21ac4..15578ea90 100644
--- a/simpleclient_servlet_common/pom.xml
+++ b/simpleclient_servlet_common/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_servlet_common</artifactId>
@@ -40,12 +40,12 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <!-- Test Dependencies Follow -->
         <dependency>
@@ -57,7 +57,7 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_servlet_jakarta/pom.xml b/simpleclient_servlet_jakarta/pom.xml
index 1707a0b51..766cfd7f1 100644
--- a/simpleclient_servlet_jakarta/pom.xml
+++ b/simpleclient_servlet_jakarta/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_servlet_jakarta</artifactId>
@@ -40,17 +40,17 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_servlet_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>jakarta.servlet</groupId>
@@ -68,19 +68,19 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.eclipse.jetty</groupId>
             <artifactId>jetty-servlet</artifactId>
-            <version>11.0.2</version>
+            <version>11.0.7</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.mockito</groupId>
             <artifactId>mockito-core</artifactId>
-            <version>2.28.2</version>
+            <version>4.3.1</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_servlet_jakarta/src/main/java/io/prometheus/client/servlet/jakarta/exporter/MetricsServlet.java b/simpleclient_servlet_jakarta/src/main/java/io/prometheus/client/servlet/jakarta/exporter/MetricsServlet.java
index bf8646af7..4617ebd48 100644
--- a/simpleclient_servlet_jakarta/src/main/java/io/prometheus/client/servlet/jakarta/exporter/MetricsServlet.java
+++ b/simpleclient_servlet_jakarta/src/main/java/io/prometheus/client/servlet/jakarta/exporter/MetricsServlet.java
@@ -40,6 +40,7 @@ public MetricsServlet(CollectorRegistry registry, Predicate<String> sampleNameFi
   @Override
   public void init(ServletConfig servletConfig) throws ServletException {
     try {
+      super.init(servletConfig);
       exporter.init(wrap(servletConfig));
     } catch (ServletConfigurationException e) {
       throw new ServletException(e);
diff --git a/simpleclient_spring_boot/pom.xml b/simpleclient_spring_boot/pom.xml
index 7a340dbb5..7c69ce2b2 100644
--- a/simpleclient_spring_boot/pom.xml
+++ b/simpleclient_spring_boot/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_spring_boot</artifactId>
@@ -51,32 +51,32 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
           <groupId>io.prometheus</groupId>
           <artifactId>simpleclient_spring_web</artifactId>
-          <version>0.14.1</version>
+          <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-actuator</artifactId>
-            <version>1.5.4.RELEASE</version>
+            <version>1.5.22.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-aop</artifactId>
-            <version>1.5.4.RELEASE</version>
+            <version>1.5.22.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>3.4</version>
+            <version>3.12.0</version>
         </dependency>
 
         <!-- Test Dependencies Follow -->
@@ -95,13 +95,13 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
-            <version>1.5.4.RELEASE</version>
+            <version>1.5.22.RELEASE</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
-            <version>1.5.4.RELEASE</version>
+            <version>1.5.22.RELEASE</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_spring_web/pom.xml b/simpleclient_spring_web/pom.xml
index a8bfe77c7..f0ff5280b 100644
--- a/simpleclient_spring_web/pom.xml
+++ b/simpleclient_spring_web/pom.xml
@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_spring_web</artifactId>
@@ -51,37 +51,37 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-web</artifactId>
-            <version>4.3.9.RELEASE</version>
+            <version>4.3.30.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-aop</artifactId>
-            <version>4.3.9.RELEASE</version>
+            <version>4.3.30.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-context</artifactId>
-            <version>4.3.9.RELEASE</version>
+            <version>4.3.30.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjweaver</artifactId>
-            <version>1.8.6</version>
+            <version>1.9.7</version>
         </dependency>
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>3.4</version>
+            <version>3.12.0</version>
         </dependency>
 
         <!-- Test Dependencies Follow -->
@@ -94,7 +94,7 @@
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>
-            <version>4.2.3.RELEASE</version>
+            <version>4.3.30.RELEASE</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
diff --git a/simpleclient_tracer/pom.xml b/simpleclient_tracer/pom.xml
index 14d573067..dd646182e 100644
--- a/simpleclient_tracer/pom.xml
+++ b/simpleclient_tracer/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>parent</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>simpleclient_tracer</artifactId>
@@ -18,7 +18,7 @@
       <dependency>
         <groupId>io.opentelemetry</groupId>
         <artifactId>opentelemetry-api</artifactId>
-        <version>1.0.1</version>
+        <version>1.10.1</version>
       </dependency>
     </dependencies>
   </dependencyManagement>
diff --git a/simpleclient_tracer/simpleclient_tracer_common/pom.xml b/simpleclient_tracer/simpleclient_tracer_common/pom.xml
index bf4498212..acc02c7ce 100644
--- a/simpleclient_tracer/simpleclient_tracer_common/pom.xml
+++ b/simpleclient_tracer/simpleclient_tracer_common/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>simpleclient_tracer</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>simpleclient_tracer_common</artifactId>
diff --git a/simpleclient_tracer/simpleclient_tracer_otel/pom.xml b/simpleclient_tracer/simpleclient_tracer_otel/pom.xml
index 335213475..f60633366 100644
--- a/simpleclient_tracer/simpleclient_tracer_otel/pom.xml
+++ b/simpleclient_tracer/simpleclient_tracer_otel/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>simpleclient_tracer</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>simpleclient_tracer_otel</artifactId>
diff --git a/simpleclient_tracer/simpleclient_tracer_otel_agent/pom.xml b/simpleclient_tracer/simpleclient_tracer_otel_agent/pom.xml
index 82284541d..9ed206650 100644
--- a/simpleclient_tracer/simpleclient_tracer_otel_agent/pom.xml
+++ b/simpleclient_tracer/simpleclient_tracer_otel_agent/pom.xml
@@ -5,7 +5,7 @@
   <parent>
     <groupId>io.prometheus</groupId>
     <artifactId>simpleclient_tracer</artifactId>
-    <version>0.14.1</version>
+    <version>0.15.1-SNAPSHOT</version>
   </parent>
 
   <artifactId>simpleclient_tracer_otel_agent</artifactId>
diff --git a/simpleclient_vertx/pom.xml b/simpleclient_vertx/pom.xml
index ca298114c..31619a4b3 100644
--- a/simpleclient_vertx/pom.xml
+++ b/simpleclient_vertx/pom.xml
@@ -17,7 +17,7 @@
     <parent>
         <groupId>io.prometheus</groupId>
         <artifactId>parent</artifactId>
-        <version>0.14.1</version>
+        <version>0.15.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>simpleclient_vertx</artifactId>
@@ -52,17 +52,17 @@
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.prometheus</groupId>
             <artifactId>simpleclient_common</artifactId>
-            <version>0.14.1</version>
+            <version>0.15.1-SNAPSHOT</version>
         </dependency>
         <dependency>
             <groupId>io.vertx</groupId>
             <artifactId>vertx-web</artifactId>
-            <version>3.3.2</version>
+            <version>3.5.4</version>
             <scope>provided</scope>
         </dependency>
         <!-- Test Dependencies Follow -->
@@ -75,7 +75,7 @@
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>2.6.0</version>
+            <version>3.22.0</version>
             <scope>test</scope>
         </dependency>
     </dependencies>