diff --git a/.gitignore b/.gitignore
index d4c5dd7..232ed2c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -225,6 +225,9 @@
 /lib/haxe/test/data.tmp
 /lib/hs/dist
 /lib/java/.gradle
+/lib/java/gradle/wrapper
+/lib/java/gradlew
+/lib/java/gradlew.bat
 /lib/java/android/.gradle
 /lib/java/build
 /lib/java/out
diff --git a/.travis.yml b/.travis.yml
index 41a8a3f..8b08449 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -61,11 +61,6 @@
     - stage: docker
       script: true
       env:
-        - JOB="Docker Build ubuntu-xenial 16.04 LTS"
-        - DISTRO=ubuntu-xenial
-        - TRAVIS_BUILD_STAGE=docker
-    - script: true
-      env:
         - JOB="Docker Build ubuntu-bionic 18.04 LTS"
         - DISTRO=ubuntu-bionic
         - TRAVIS_BUILD_STAGE=docker
@@ -130,12 +125,6 @@
         - DISTRO=ubuntu-bionic
         - SCRIPT="autotools.sh"
 
-    - script: build/docker/run.sh
-      env:
-        - JOB="Autotools (Ubuntu Xenial)"
-        - DISTRO=ubuntu-xenial
-        - SCRIPT="autotools.sh"
-
     # ------------------------- phase: cmake ------------------------
     - script: build/docker/run.sh
       env:
diff --git a/build/docker/README.md b/build/docker/README.md
index 1746d6d..4b09700 100644
--- a/build/docker/README.md
+++ b/build/docker/README.md
@@ -52,9 +52,9 @@
 
 ### Ubuntu ###
 
-* bionic (stable, current)
-* artful (previous stable)
-* xenial (legacy)
+* focal (stable, current)
+* bionic (previous stable)
+* jammy (next stable, WIP)
 
 ## Unsupported Containers ##
 
diff --git a/build/docker/ubuntu-xenial/Dockerfile b/build/docker/old/ubuntu-xenial/Dockerfile
similarity index 100%
rename from build/docker/ubuntu-xenial/Dockerfile
rename to build/docker/old/ubuntu-xenial/Dockerfile
diff --git a/lib/kotlin/settings.gradle.kts b/lib/kotlin/settings.gradle.kts
index 2eff402..c252add 100644
--- a/lib/kotlin/settings.gradle.kts
+++ b/lib/kotlin/settings.gradle.kts
@@ -19,14 +19,7 @@
 pluginManagement {
     plugins {
         kotlin("jvm") version "1.6.10"
-        // per https://github.com/cortinico/ktfmt-gradle/tags the latest version requires Gradle 7.4 which in turn
-        // requires Java 11, failing the xenial build which is still on Java 8. Here we both configure the plugin
-        // but with different version, and only enabling ktfmt configure for Java 11+, to make the legacy build happy
-        if (JavaVersion.current().isJava11Compatible) {
-            id("com.ncorti.ktfmt.gradle") version "0.8.0"
-        } else {
-            id("com.ncorti.ktfmt.gradle") version "0.5.0"
-        }
+        id("com.ncorti.ktfmt.gradle") version "0.8.0"
     }
 }
 
diff --git a/lib/perl/build-cpan-dist.sh b/lib/perl/build-cpan-dist.sh
index ac0ff0b..b9250f4 100755
--- a/lib/perl/build-cpan-dist.sh
+++ b/lib/perl/build-cpan-dist.sh
@@ -2,7 +2,7 @@
 #
 # This script is intended to be used after tagging the repository and updating
 # the version files for a release.  It will create a CPAN archive.  Run this
-# from inside a docker image like ubuntu-xenial.
+# from inside a docker image like ubuntu-focal.
 #
 
 set -e