# `memcachedTestHook` {#sec-memcachedTestHook} This hook starts a Memcached server during `checkPhase`. Example: ```nix { stdenv, memcachedTestHook, }: stdenv.mkDerivation { # ... nativeCheckInputs = [ memcachedTestHook ]; } ``` If you use a custom `checkPhase`, remember to add the `runHook` calls: ```nix { checkPhase = '' runHook preCheck # ... your tests runHook postCheck ''; } ``` ## Variables {#sec-memcachedTestHook-variables} Bash-only variables: - `memcachedTestPort`: Port to use by Memcached. Defaults to `11211` Example usage: ```nix { stdenv, memcachedTestHook }: stdenv.mkDerivation { # ... nativeCheckInputs = [ memcachedTestHook ]; preCheck = '' memcachedTestPort=1234; ''; }