diff --git a/.github/workflows/bundle-ucm.yaml b/.github/workflows/bundle-ucm.yaml
index 281e891118..1866f5b0ad 100644
--- a/.github/workflows/bundle-ucm.yaml
+++ b/.github/workflows/bundle-ucm.yaml
@@ -13,7 +13,7 @@ on:
         required: true
 
 env:
-  racket_version: "8.7"
+  racket_version: "8.12"
 
 defaults:
   run:
diff --git a/.github/workflows/ci-build-jit-binary.yaml b/.github/workflows/ci-build-jit-binary.yaml
index 5b3244e2f0..477f34cf91 100644
--- a/.github/workflows/ci-build-jit-binary.yaml
+++ b/.github/workflows/ci-build-jit-binary.yaml
@@ -10,7 +10,7 @@ defaults:
 env:
   jit_src: unison-jit-src/
   jit_dist: unison-jit-dist/
-  racket_version: "8.7"
+  racket_version: "8.12"
 
 jobs:
   build-jit-binary:
diff --git a/.github/workflows/ci-test-jit.yaml b/.github/workflows/ci-test-jit.yaml
index 6162c535f2..0df8205ee7 100644
--- a/.github/workflows/ci-test-jit.yaml
+++ b/.github/workflows/ci-test-jit.yaml
@@ -4,7 +4,7 @@ on:
   workflow_call:
 
 env:
-  runtime_tests_version: "@unison/runtime-tests/main"
+  runtime_tests_version: "@unison/runtime-tests/@kylegoetz/udp"
   # for best results, this should match the path in ci.yaml too; but GH doesn't make it easy to share them.
   runtime_tests_codebase: "~/.cache/unisonlanguage/runtime-tests.unison"
 
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index bee8575752..91653159b4 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -24,7 +24,7 @@ env:
   jit_src_scheme: unison-jit-src/scheme-libs/racket
   jit_dist: unison-jit-dist
   jit_generator_os: ubuntu-20.04
-  runtime_tests_version: "@unison/runtime-tests/main"
+  runtime_tests_version: "@unison/runtime-tests/@kylegoetz/udp"
   runtime_tests_codebase: "~/.cache/unisonlanguage/runtime-tests.unison"
 
   # locations of some files that will indicate whether we need to re-run certain steps