diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2f50938..4696541 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -35,10 +35,21 @@ jobs:
           export TEST_PHP_EXECUTABLE="$(command -v php)"
           RUN_TESTS="$(find /usr/lib/php -name run-tests.php | head -n1)"
           echo "Using runner: ${RUN_TESTS}"
-          php "${RUN_TESTS}" -q --show-diff --show-slow 1000 --set-timeout 120 tests
+          if [ -z "${RUN_TESTS}" ]; then
+            echo "run-tests.php not found under /usr/lib/php" >&2
+            exit 1
+          fi
+          # run-tests.php writes run-test-info.php next to itself, but the system
+          # build dir is not writable by the runner user. Copy it to a writable
+          # temp dir so it can generate its helper files.
+          cp "${RUN_TESTS}" "${RUNNER_TEMP:-/tmp}/run-tests.php"
+          php "${RUNNER_TEMP:-/tmp}/run-tests.php" -q --show-diff --show-slow 1000 --set-timeout 120 tests
       - name: Custom runner smoke check
         env:
           CUSTOM_PHPT_RUNNER: 1
+          # Make phpt_runner.php load the extension in the child PHP process,
+          # otherwise every test is reported as SKIPPED.
+          PHPT_ADD_EXTENSION: 1
         run: |
           for f in tests/*.phpt; do php -d extension=blake3 .github/phpt_runner.php "$f" || exit 1; done
 
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 57ad10f..7b16d88 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -4,7 +4,7 @@ on:
   workflow_dispatch:
     inputs:
       version:
-        description: 'Version as year.month.day-subversion (e.g. 2026.9.13-1)'
+        description: 'Version as year.month.day.subversion (e.g. 2026.9.13.1)'
         required: true
         type: string
 
@@ -44,8 +44,10 @@ jobs:
           set -euo pipefail
           # Accept the version with or without the leading "v"
           VERSION="${VERSION_INPUT#v}"
-          if ! [[ "${VERSION}" =~ ^[0-9]{4}\.[0-9]{1,2}\.[0-9]{1,2}-[0-9]+$ ]]; then
-            echo "Invalid version '${VERSION}'. Expected year.month.day-subversion, e.g. 2026.9.13-1" >&2
+          # Must be a Composer-valid version: four dot-separated numeric parts,
+          # e.g. 2026.9.13.1 (a dash suffix like 2026.9.13-1 is NOT valid).
+          if ! [[ "${VERSION}" =~ ^[0-9]{4}\.[0-9]{1,2}\.[0-9]{1,2}\.[0-9]+$ ]]; then
+            echo "Invalid version '${VERSION}'. Expected year.month.day.subversion, e.g. 2026.9.13.1" >&2
             exit 1
           fi
           echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
diff --git a/tests/Dockerfile b/tests/Dockerfile
index f51ddb5..2f7eef5 100644
--- a/tests/Dockerfile
+++ b/tests/Dockerfile
@@ -39,7 +39,7 @@ RUN printf '%s\n' \
   '  exec php "${RUN_TESTS}" -q --show-diff --show-slow 1000 --set-timeout 120 tests' \
   'else' \
   '  echo "run-tests.php not found, using custom runner"' \
-  '  for f in tests/*.phpt; do PHPT_ADD_EXTENSION= php .github/phpt_runner.php "$f" || exit 1; done' \
+  '  for f in tests/*.phpt; do PHPT_ADD_EXTENSION=1 php .github/phpt_runner.php "$f" || exit 1; done' \
   'fi' \
   > /usr/local/bin/run-phpt && chmod +x /usr/local/bin/run-phpt