diff --git a/.github/go.mod b/.github/go.mod
index 3f38e2f0..9c70ef9a 100644
--- a/.github/go.mod
+++ b/.github/go.mod
@@ -1,7 +1,10 @@
 module sigstore/sigstore-python
 
-go 1.23
+go 1.23.1
+
 toolchain go1.23.5
 
 // We don't have a Go module here but this file is picked up by dependabot
 // and this will automatically update the dependency when needed.
+
+require github.com/sigstore/timestamp-authority v1.2.4
diff --git a/.github/go.sum b/.github/go.sum
new file mode 100644
index 00000000..42d5069e
--- /dev/null
+++ b/.github/go.sum
@@ -0,0 +1,2 @@
+github.com/sigstore/timestamp-authority v1.2.4 h1:RjXZxOWorEiem/uSr0pFHVtQpyzpcFxgugo5jVqm3mw=
+github.com/sigstore/timestamp-authority v1.2.4/go.mod h1:ExrbobKdEuwuBptZIiKp1IaVBRiUeKbiuSyZTO8Okik=