Crust – A CLI framework for TypeScript and Bun
We've been building Crust (https://crustjs.com/), a TypeScript-first, Bun-native CLI framework with zero dependencies. It's been powering our core product internally for a while, and we're now open-sourcing it. The problem we kept running into: existing CLI frameworks in the JS ecosystem are either minimal arg parsers where you wire everything yourself, or heavyweight frameworks with large dependency trees and Node-era assumptions. We wanted something in between. What Crust does differently: - Full type inference from definitions — args and flags are inferred automatically. No…
In plain words
Crust is a TypeScript-first CLI framework built for Bun with zero dependencies. It sits between minimal argument parsers and heavyweight frameworks, offering full type inference for arguments and flags without manual annotations. The framework includes compile-time validation to catch configuration errors like flag collisions before runtime. Designed for developers building command-line tools in TypeScript who want built-in structure without large dependency overhead.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
We've been building Crust (https://crustjs.com/), a TypeScript-first, Bun-native CLI framework with zero dependencies. It's been powering our core product internally for a while, and we're now open-sourcing it. The problem we kept running into: existing CLI frameworks in the JS ecosystem are either minimal arg parsers where you wire everything yourself, or heavyweight frameworks with large dependency trees and Node-era assumptions. We wanted something in between. What Crust does differently: - Full type inference from definitions — args and flags are inferred automatically. No manual type annotations, no generics to wrangle. You define a flag as type: "string" and it flows through to your handler. - Compile-time validation — catches flag alias collisions and variadic arg mistakes before your code runs, not at runtime. - Zero runtime dependencies — @crustjs/core is ~3.6kB gzipped (21kB install). For comparison: yargs is 509kB, oclif is 411kB. - Composable modules — core, plugins, prompts, styling, validation, and build tooling are all separate packages. Install only what you need. - Plugin system — middleware-based with lifecycle hooks (preRun/postRun). Official plugins for help, version, and shell autocompletion. - Built for Bun — no Node compatibility layers, no legacy baggage. Quick example: import { Crust } from "@crustjs/core"; import { helpPlugin, versionPlugin } from "@crustjs/plugins"; const main = new Crust("greet") .args([{ name: "name", type: "string", default: "world" }]) .flags({ shout: { type: "boolean", short: "s" } }) .use(helpPlugin()) .use(versionPlugin("1.0.0")) .run(({ args, flags }) => { const msg = `Hello, ${args.name}!`; console.log(flags.shout ? msg.toUpperCase() : msg); }); await main.execute(); Scaffold a new project: bun create crust my-cli Site: https://crustjs.com GitHub: https://github.com/chenxin-yan/crust Happy to answer any questions about the design decisions or internals.
More dev tools this month
the category →
Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com
OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 1d ago · opentrailpaper.com
Launched alongside, March 2026
the whole month →
Switch from ChatGPT to Claude with import memory feature
AI · Mar 2026 · claude.com
