# Timer Schedule one-shot or repeating scene-clock callbacks. [Feature status and language/platform compatibility](https://rustic-game-engine.pages.dev/markdown/reference/compatibility.md) Choose an API to see its signature, parameters, examples and behavior. ## APIs - [Timer.after()](https://rustic-game-engine.pages.dev/markdown/api/timer/after.md) - [Timer.every()](https://rustic-game-engine.pages.dev/markdown/api/timer/every.md) ## Module guide ## Setup and language support These engine-owned services work in Lua 5.4, Luau, JavaScript, Python, C, C++, C#, Java, PHP, and HTML inline JavaScript. Follow [Use gameplay actions](https://rustic-game-engine.pages.dev/markdown/guides/gameplay-actions.md) to create and attach a script, install external toolchains, and choose the correct language binding. PHP and HTML scripts belong under `ui/`; CSS alone runs no gameplay code. The Calls section uses JavaScript signatures. The function examples below include native syntax for all ten script types, including SDK-specific alternatives and limitations. Attach a JavaScript Object Component script to the specified target and press **Play**. Globals are supplied by the engine. Schedule actions from `Start` or a callback, rather than at script top level. Native languages use typed options and their own builder conventions; see the guide's language bindings. ## Parameters Delay is finite non-negative seconds. Interval is positive finite seconds. Optional count is a positive integer; omit it for indefinite repetition. In C, count 0 means indefinite repetition. Callbacks take no timer argument. ## Return and timing Both return pausable, resumable, cancellable operation handles. Deliveries are queued during Update; they do not block the scripting runtime. ## Behavior and limitations - The Console prints four ticks at half-second intervals, delayed at two seconds, and timer finished on repeat completion. - Large frames preserve leftover time and can deliver multiple ticks. Keep callbacks short and within the runtime budget. - Clock scaling and pause affect timers. Cancel prevents future delivery and does not invoke onFinished. - Zero-duration infinite loops are rejected or fail within a bounded scheduler step budget. - Check script attachment, enabled state and the Console when an operation fails. Asynchronous errors also appear in operation state. Callback exceptions disable the owner and clean up its actions. - Owner destruction, disable, successful reload or Stop cleans up owned actions and subscriptions. Failed reload retains the previous behavior's operations. See [Operation handles](https://rustic-game-engine.pages.dev/markdown/api/operation-handles.md) for controls and lifetime details.