diff --git a/scripts/ci-run.sh b/scripts/ci-run.sh
index 9c32a3a..92c1042 100755
--- a/scripts/ci-run.sh
+++ b/scripts/ci-run.sh
@@ -19,6 +19,17 @@ if [ -z "$JOB" ]; then
   exit 1
 fi
 
+# CoreCI's shell-isolated executor (buildIsolatedEnv) does NOT forward
+# Go toolchain env vars (GOROOT, GOPATH, GOCACHE, GOMODCACHE are in the
+# systemVars deny-list). Re-derive them from the `go` binary on PATH so
+# Go commands work in the shell-isolated executor.
+if command -v go >/dev/null 2>&1; then
+  export GOROOT="${GOROOT:-$(go env GOROOT)}"
+  export GOPATH="${GOPATH:-$(go env GOPATH)}"
+  export GOCACHE="${GOCACHE:-$(go env GOCACHE)}"
+  export GOMODCACHE="${GOMODCACHE:-$(go env GOMODCACHE)}"
+fi
+
 info() { echo "ci-run: $*"; }
 err()  { echo "ci-run: error: $*" >&2; exit 1; }