diff --git a/.travis.yml b/.travis.yml
index deadaf32..938f39c5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,10 +5,14 @@ scala:
   - 2.12.6
   - 2.13.0-M4
 jdk:
-  - openjdk7
+  - openjdk6
   - oraclejdk8
 env:
   global:
+    # force jdk 8 for sbt due to sonatype droping support for jdk6 on https (TLS 1.0)
+    # https://stackoverflow.com/questions/50824789/why-am-i-getting-received-fatal-alert-protocol-version-or-peer-not-authentic/50824799#50824799
+    - JAVA_HOME: /usr/lib/jvm/java-8-oracle
+
     # PGP_PASSPHRASE
     - secure: "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"
     # SONA_USER
@@ -23,10 +27,10 @@ env:
 matrix:
   exclude:
     # > 2.12 requires jdk8
-    - jdk: openjdk7
+    - jdk: openjdk6
       scala: 2.12.6
 
-    - jdk: openjdk7
+    - jdk: openjdk6
       scala: 2.13.0-M4
 
     # ?
@@ -43,11 +47,17 @@ matrix:
       jdk: oraclejdk8
       env: TEST_SCALAFIX=true
 
+    - addons:
+       apt:
+         packages:
+           - openjdk-6-jdk
+     jdk: openjdk6
+
 # | jdk         |   scala   | scala target | scala target version | scalafix test |
 # | ----------- | --------- | ------------ | -------------------- |---------------|
-# |    openjdk7 | 2.11.12   | jvm          |                      |               |
-# |    openjdk7 | 2.11.12   | js           | 0.6.23               |               |
-# |    openjdk7 | 2.11.12   | js           | 1.0.0-M3             |               |
+# |    openjdk6 | 2.11.12   | jvm          |                      |               |
+# |    openjdk6 | 2.11.12   | js           | 0.6.23               |               |
+# |    openjdk6 | 2.11.12   | js           | 1.0.0-M3             |               |
 # |  oraclejdk8 | 2.12.6    | jvm          |                      |               |
 # |  oraclejdk8 | 2.12.6    | js           | 0.6.23               |               |
 # |  oraclejdk8 | 2.12.6    | js           | 1.0.0-M3             |               |
diff --git a/README.md b/README.md
index 74d90f4e..487ea2d0 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@ To use this library, add the following to your build.sbt:
 libraryDependencies += "org.scala-lang.modules" %% "scala-collection-compat" % "0.1.1"
 ```
 
+
 Note that there are multiple ways to cross-build projects, see https://github.com/scala/collection-strawman/wiki/FAQ#how-do-i-cross-build-my-project-against-scala-212-and-scala-213.
 
 Also note that this library has not fully stabilized yet. We expect that new, binary incompatible releases of this library will be published (for 2.11, 2.12) until Scala 2.13 is getting close to its final state. Therefore you might want to avoid adding a dependency on that library to your 2.11 / 2.12 artifacts for the time being.
diff --git a/admin/build.sh b/admin/build.sh
index 52a555dd..7993b08e 100755
--- a/admin/build.sh
+++ b/admin/build.sh
@@ -62,4 +62,4 @@ if [[ "$TRAVIS_TAG" =~ $tagPat ]]; then
   fi
 fi
 
-sbt -Dhttps.protocols=TLSv1.2 -sbt-dir=/home/travis/.sbt ";$crossScalaVersion ;$publishVersion ;$projectPrefix/clean ;$testProjectPrefix/test ;$projectPrefix/publishLocal ;$publishTask"
+sbt ";$crossScalaVersion ;$publishVersion ;$projectPrefix/clean ;$testProjectPrefix/test ;$projectPrefix/publishLocal ;$publishTask"
diff --git a/build.sbt b/build.sbt
index cc7362c6..939a91d4 100644
--- a/build.sbt
+++ b/build.sbt
@@ -32,7 +32,24 @@ lazy val compat = crossProject(JSPlatform, JVMPlatform)
   )
   .jvmSettings(
     OsgiKeys.exportPackage := Seq(s"scala.collection.compat.*;version=${version.value}"),
-    libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % "test"
+    libraryDependencies += "com.novocode" % "junit-interface" % "0.11" % "test",
+    javaHome := {
+      val oldValue = javaHome.value
+      val isOnCi = sys.env.get("CI").isDefined
+
+      if (isOnCi) {
+        // switch back to the jdk set by the build matrix
+        val ciJavaHome =
+          sys.env("TRAVIS_JDK_VERSION") match {
+            case "openjdk6"   => "/usr/lib/jvm/java-6-openjdk-amd64"
+            case "oraclejdk8" => "/usr/lib/jvm/java-8-oracle"
+          }
+
+        println(s"using JAVA_HOME: $ciJavaHome")
+        Some(file(ciJavaHome))
+      }
+      else oldValue
+    }
   )
   .jsSettings(
     scalacOptions += {
diff --git a/compat/src/test/scala/test/scala/collection/JdkVersionTest.scala b/compat/src/test/scala/test/scala/collection/JdkVersionTest.scala
new file mode 100644
index 00000000..1e5ac7cc
--- /dev/null
+++ b/compat/src/test/scala/test/scala/collection/JdkVersionTest.scala
@@ -0,0 +1,25 @@
+package test.scala.collection
+
+import org.junit.Assert._
+import org.junit.Test
+
+class JdkVersionTest {
+
+  @Test
+  def testJavaVersion: Unit = {
+    val isOnCi = sys.env.get("CI").isDefined
+
+    if (isOnCi) {
+      val travisJdkVersion = sys.env("TRAVIS_JDK_VERSION")
+      val jdkVersion = sys.props("java.specification.version")
+
+      if (travisJdkVersion == "openjdk6") {
+        assertEquals(jdkVersion, "1.8")
+      } else if (travisJdkVersion == "oraclejdk8") {
+        assertEquals(jdkVersion, "1.6")
+      } else {
+        throw new Exception(s"Unknown CI jdk version: $travisJdkVersion")
+      }
+    }
+  }
+}