diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 352bae1..4be91d4 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go: ['1.15', '1.16', '1.17', '1.18', '1.19', '1.20']
+        go: ['1.21', '1.22', '1.23']
 
     steps:
       - name: Set up Go
diff --git a/go.mod b/go.mod
index 507295d..6d21a95 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
 module github.com/jonboulle/clockwork
 
-go 1.15
+go 1.21