Coax

The desktop app for your .http files.

A free, open-source (MIT), cross-platform desktop client for .http files — the format used by VS Code REST Client and JetBrains HTTP Client. Open existing .http files, edit them in a polished UI, manage environments and secrets, and execute requests against any HTTP endpoint.

Built with Electron + TypeScript and the Melodic component library.

Download: grab the latest installer for macOS, Windows, or Linux from GitHub Releases.

┌─────────────────────────────────────────────────────────────────┐
│  ●─● Coax   Env: [dev ▾] + ───── tab1 · tab2 · + ───  ⚙ ⬇ ⬆ ☾ │
├──────────────────┬──────────────────────────────────────────────┤
│ COLLECTIONS      │ Chain name: getToken                          │
│  ▾ oneroster     │ [POST ▾] {{baseUrl}}/token        [ Send → ] │
│    ▸ Auth        │  Params · Headers · Body · Auth · Vars · cURL │
│    ▾ Users       │  ┌───────────────────────────────────────┐   │
│      • Get all   │  │ { "clientCode": "...", "scope": "..." │   │
│      • Get by id │  │ }                                     │   │
│      • New       │  └───────────────────────────────────────┘   │
│  ▸ Schools       │ ─── 200 OK · 142 ms · 4.2 KB ─────────────── │
│                  │  Body · Headers · Raw                         │
│                  │  { "access_token": "eyJhbGc...", ... }        │
└──────────────────┴──────────────────────────────────────────────┘
  ● Default · ~/Library/Application Support/Coax/workspaces/...

Quick start

Install from GitHub Releases, or build from source:

git clone https://github.com/MelodicDevelopment/coax.git
cd coax
npm install
npm run dev          # launches the app in development mode

To build a packaged app for your OS:

npm run build
npm run package      # produces dist/Coax-X.Y.Z-<arch>.dmg|exe|AppImage

(Unsigned local builds work fine — the signing/notarization steps only run when the corresponding credentials are present in your environment; see .env.example.)

Open the app, click the ⬇ Import button in the header, and pick a .http file. The example files in examples/ are a good starting point.

What works

• Open .http files as collections — variable definitions become an environment, ### Title blocks become requests, ############ comment dividers become folders, # @name foo becomes a chain name
• Send any HTTP request — GET/POST/PUT/PATCH/DELETE/HEAD/OPTIONS, with custom headers, JSON/form/text/multipart bodies, query params, and Bearer/Basic/API Key auth
• Variable substitution with {{var}} syntax across URL, headers, and body
• Layered environments — global → collection → request, plus built-ins ({{$timestamp}}, {{$guid}}, {{$randomInt 1 10}})
• Encrypted secrets — variables marked secret are encrypted at rest via Electron safeStorage
• Response chaining — reference another request's last response with {{name.response.body.$.field}}
• Live editing with autosave; tabs persist across restarts
• Export collections as .http files with secrets stripped to placeholders

Documentation

Topic	Where
Full user guide	docs/user-guide.md
Variables & environments	docs/user-guide.md#variables-and-environments
Response chaining	docs/user-guide.md#response-chaining
Keyboard shortcuts & UI tour	docs/user-guide.md#interface-tour
CLI reference (coax run in CI)	docs/cli.md
Privacy & telemetry details	docs/privacy.md
Roadmap	docs/roadmap.md
Architecture (for contributors)	docs/superpowers/specs/2026-05-14-http-ui-design.md

Project layout

src/
  parser/      .http file parser & serializer (pure TypeScript, no Electron)
  resolver/    Variable resolver: layered scopes + built-ins + JSONPath chain refs
  storage/     SQLite via better-sqlite3 — workspaces, collections, requests, envs, vars
  secrets/     Wrapper around Electron safeStorage for encrypted variables
  runner/      HTTP runner using undici (with cancel + timeout)
  ipc/         Typed IPC contract between renderer and main process
  app/         Electron main process glue (dispatcher, file dialogs, lifecycle)
  ui/          Renderer — Melodic web components
docs/          User-facing documentation
examples/      Sample .http files (OneRoster API spec)
tests/         Vitest unit + integration tests
tests-e2e/     Playwright end-to-end test against the packaged Electron app

Scripts

Command	What it does
npm run dev	Launch the app in development mode (hot reload)
npm run build	Build production bundles into out/
npm run package	Package the app into a platform installer (dist/)
npm test	Run the Vitest unit/integration suite
npm run test:e2e	Build and run the Playwright E2E test
npm run typecheck	TypeScript type check (no emit)

Tech stack

• Electron 33 with strict context isolation, no Node integration in the renderer
• TypeScript with strict, noUncheckedIndexedAccess, exactOptionalPropertyTypes
• Melodic (@melodicdev/core + @melodicdev/components) for the UI component library
• Monaco Editor for body and response code editing
• better-sqlite3 for the workspace database
• undici for HTTP execution in a dedicated Node worker
• electron-vite for the build, electron-builder for packaging
• Vitest for unit tests, Playwright for end-to-end

Contributing

Contributions are welcome — bug reports, feature requests, and pull requests. See CONTRIBUTING.md for dev setup, how to run the test suites, and what to expect from the PR process. For anything non-trivial, open an issue first so we can agree on the approach before you invest time.

Found a security issue? Please follow SECURITY.md instead of opening a public issue.

Roadmap

See docs/roadmap.md — highlights: pre-request scripts, Postman/Insomnia/Bruno importers, GraphQL/WebSocket/SSE support, and deeper git integration.

Telemetry

Coax contains optional, opt-in Sentry crash reporting. It is entirely inert unless (a) a Sentry DSN was baked in at build time and (b) you explicitly opt in when asked on first run. Builds from source have no DSN, so they never phone home at all.

License

MIT © Melodic Development.

The marketing site lives at coax.melodic.dev.