schedule a cancellable function to run once

pending-queue ensures a certain asynchronous method only run once, and queues listeners which are registered to it.

The test infrastructure is complicated because some tests are meant to be run once, and some tests are meant to be run once for each dialect, or once for each dialect from a set of dialects. Work is happening to clean this up and clarify how to deal with

Helper for react effects that only run once

Smart database seeding with run-once tracking - Core package

Code-based data migrations with a run-once ledger for SPFN apps.

Factory functions for creating isolated test databases using the template-clone pattern: migrations run **once** to build a template, then each test gets a cheap clone — no repeated migration overhead.

A noop function that can only be run once

Oils js run once plugin

Run once then retrieve

Run a particular task only once

Ready-queue ensures initialization method only run once, and queues listeners which are registered to it.

Run an array of functions in parallel

Set up Marrow in your AI agent (MCP) with one disposable command — run once via npx, nothing to install. Gets a free key, wires up MCP, installs the scout→read skill.

Execution tracer as an MCP server — record a Python/Node run once (calls, args, returns, exceptions, line probes), then query the recording instead of printf-debugging and rerunning.

Run a function exactly one time

Simply do something once, or once under a condition

The ultimate Grunt Browserify task. Run once or watch files for changes. Uses a cache for super speed (instant builds). CoffeeScript support built in. Alias mappings. Shimming. Everything in one easy to use package.

Run once

Ensure a function is only called once