diff --git a/build.gradle b/build.gradle
index 9e034a03b..2dc635638 100644
--- a/build.gradle
+++ b/build.gradle
@@ -93,17 +93,17 @@ subprojects {
     }
 
     dependencies {
-        compile "io.projectreactor:reactor-core:$reactorVersion"
-        compile "io.netty:netty-buffer:$nettyVersion"
-        compile "org.reactivestreams:reactive-streams:$reactiveStreamsVersion"
-        compile "org.slf4j:slf4j-api:$slf4jVersion"
-        compile "com.google.code.findbugs:jsr305:$jsr305Version"
-
-        testCompile "junit:junit:$junitVersion"
-        testCompile "org.mockito:mockito-core:$mockitoVersion"
-        testCompile "org.hamcrest:hamcrest-library:$hamcrestVersion"
-        testCompile "org.slf4j:slf4j-log4j12:$slf4jVersion"
-        testCompile "io.projectreactor:reactor-test:$reactorVersion"
+        compile "io.projectreactor:reactor-core:3.1.0.RC1"
+        compile "io.netty:netty-buffer:4.1.15.Final"
+        compile "org.reactivestreams:reactive-streams:1.0.1"
+        compile "org.slf4j:slf4j-api:1.7.25"
+        compile "com.google.code.findbugs:jsr305:3.0.2"
+
+        testCompile "junit:junit:4.12"
+        testCompile "org.mockito:mockito-core:2.10.0"
+        testCompile "org.hamcrest:hamcrest-library:1.3"
+        testCompile "org.slf4j:slf4j-log4j12:1.7.25"
+        testCompile "io.projectreactor:reactor-test:3.1.0.RC1"
     }
 
     publishing {
diff --git a/rsocket-core/build.gradle b/rsocket-core/build.gradle
index 24363b91e..7a026d3d2 100644
--- a/rsocket-core/build.gradle
+++ b/rsocket-core/build.gradle
@@ -17,13 +17,13 @@
 apply plugin: 'me.champeau.gradle.jmh'
 
 jmh {
-    jmhVersion = "$jmhVersion"
+    jmhVersion = "1.19"
     profilers = ['gc']
     zip64 = true
     duplicateClassesStrategy = DuplicatesStrategy.WARN
 }
 
 dependencies {
-    jmh "org.openjdk.jmh:jmh-core:$jmhVersion"
-    jmh "org.openjdk.jmh:jmh-generator-annprocess:$jmhVersion"
+    jmh "org.openjdk.jmh:jmh-core:1.19"
+    jmh "org.openjdk.jmh:jmh-generator-annprocess:1.19"
 }
diff --git a/rsocket-examples/build.gradle b/rsocket-examples/build.gradle
index cb5b29b95..fd154cf64 100644
--- a/rsocket-examples/build.gradle
+++ b/rsocket-examples/build.gradle
@@ -17,7 +17,7 @@
 apply plugin: 'me.champeau.gradle.jmh'
 
 jmh {
-    jmhVersion = "$jmhVersion"
+    jmhVersion = "1.19"
     jvmArgs = ['-XX:+UseG1GC', '-Xmx4g', '-Xms4g', '-XX:+UnlockCommercialFeatures', '-XX:+FlightRecorder']
     profilers = ['gc']
     zip64 = true
@@ -32,7 +32,7 @@ dependencies {
     compile project(':rsocket-transport-netty')
     compile project(':rsocket-transport-local')
 
-    jmh "org.openjdk.jmh:jmh-generator-annprocess:$jmhVersion"
+    jmh "org.openjdk.jmh:jmh-generator-annprocess:1.19"
 
     testCompile project(':rsocket-test')
 }
diff --git a/rsocket-spectator/build.gradle b/rsocket-spectator/build.gradle
index b352e0518..f7eca3545 100644
--- a/rsocket-spectator/build.gradle
+++ b/rsocket-spectator/build.gradle
@@ -17,7 +17,7 @@
 dependencies {
     compile project(':rsocket-core')
     compile "com.netflix.spectator:spectator-api:$spectatorVersion"
-    compile "org.hdrhistogram:HdrHistogram:$hdrHistogramVersion"
+    compile "org.hdrhistogram:HdrHistogram:2.1.9"
 
     testCompile project(':rsocket-test')
 }
diff --git a/rsocket-tck-drivers/build.gradle b/rsocket-tck-drivers/build.gradle
index c1be506d4..ce4dc075d 100644
--- a/rsocket-tck-drivers/build.gradle
+++ b/rsocket-tck-drivers/build.gradle
@@ -33,9 +33,9 @@ dependencies {
     compile project(':rsocket-transport-netty')
     compile project(':rsocket-transport-local')
     compile project(':rsocket-test')
-    compile "com.fasterxml.jackson.core:jackson-core:$jacksonVersion"
-    compile "com.fasterxml.jackson.core:jackson-databind:$jacksonVersion"
-    compile "org.apache.commons:commons-lang3:$commonsLang3Version"
-    compile "io.airlift:airline:$airlineVersion"
+    compile "com.fasterxml.jackson.core:jackson-core:2.9.1"
+    compile "com.fasterxml.jackson.core:jackson-databind:2.9.1"
+    compile "org.apache.commons:commons-lang3:3.6"
+    compile "io.airlift:airline:0.8"
     compile "io.reactivex.rxjava2:rxjava:$rxjavaVersion"
 }
diff --git a/rsocket-test/build.gradle b/rsocket-test/build.gradle
index b04798e3d..a72a0b9c3 100644
--- a/rsocket-test/build.gradle
+++ b/rsocket-test/build.gradle
@@ -16,9 +16,9 @@
 
 dependencies {
     compile project(':rsocket-core')
-    compile "junit:junit:$junitVersion"
-    compile "org.mockito:mockito-core:$mockitoVersion"
-    compile "org.hamcrest:hamcrest-library:$hamcrestVersion"
-    compile "org.hdrhistogram:HdrHistogram:$hdrHistogramVersion"
-    compile "io.projectreactor:reactor-test:$reactorVersion"
+    compile "junit:junit:4.12"
+    compile "org.mockito:mockito-core:2.10.0"
+    compile "org.hamcrest:hamcrest-library:1.3"
+    compile "org.hdrhistogram:HdrHistogram:2.1.9"
+    compile "io.projectreactor:reactor-test:3.1.0.RC1"
 }
diff --git a/rsocket-transport-aeron/build.gradle b/rsocket-transport-aeron/build.gradle
index d797b09a2..f20e7cb44 100644
--- a/rsocket-transport-aeron/build.gradle
+++ b/rsocket-transport-aeron/build.gradle
@@ -16,7 +16,7 @@
 
 dependencies {
     compile project(':rsocket-core')
-    compile "io.aeron:aeron-all:$aeronVersion"
+    compile "io.aeron:aeron-all:1.4.1"
 
     testCompile project(':rsocket-test')
 }
diff --git a/rsocket-transport-netty/build.gradle b/rsocket-transport-netty/build.gradle
index 3333d4750..28b1d75e5 100644
--- a/rsocket-transport-netty/build.gradle
+++ b/rsocket-transport-netty/build.gradle
@@ -16,11 +16,11 @@
 
 dependencies {
     compile project(':rsocket-core')
-    compile "io.projectreactor.ipc:reactor-netty:$reactorNettyVersion"
-    compile "io.netty:netty-handler:$nettyVersion"
-    compile "io.netty:netty-handler-proxy:$nettyVersion"
-    compile "io.netty:netty-codec-http:$nettyVersion"
-    compile "io.netty:netty-transport-native-epoll:$nettyVersion"
+    compile "io.projectreactor.ipc:reactor-netty:0.7.0.M2"
+    compile "io.netty:netty-handler:4.1.15.Final"
+    compile "io.netty:netty-handler-proxy:4.1.15.Final"
+    compile "io.netty:netty-codec-http:4.1.15.Final"
+    compile "io.netty:netty-transport-native-epoll:4.1.15.Final"
 
     testCompile project(':rsocket-test')
 }