KELD

The desktop framework that replaces Electron without a rewrite. Rust core · Bun-powered JS/TS main process · system webviews · security by default. By GyldLab.

Status: pre-alpha — public repo contains the implementation; research and architecture specs are maintained privately by the GyldLab team.

The idea in 30 seconds

Every Electron alternative asks you to rewrite your app. Keld doesn't.

cd my-electron-app
bunx keld migrate   # analyzes your app, generates config, aliases electron → @keld/electron
bunx keld dev       # your app runs — no Chromium bundle, no Node, no rewrite
bunx keld build     # signed installers + kilobyte-scale delta updates

Under the hood, Keld replaces Electron's architecture, not its API:

• A prebuilt Rust host owns windows, webviews, and every native API — you never install a Rust toolchain.
• Your JS/TS main process runs on Bun as a supervised, unprivileged child process — full npm ecosystem, no ambient OS access, crashes don't take your windows down.
• System webviews by default (WebView2 / WKWebView / WebKitGTK) with a polyfill pack and per-platform engine policy.
• Typed binary IPC (schema-first, shared-memory bulk lane, backpressured).
• Default-deny permissions generated from your code, reviewed like a lockfile.
• Delta updates (bsdiff+zstd, signed) and cross-compiled installers.

Workspace layout

crates/   keld-core · keld-wv · keld-ipc · keld-guard · keld-native · keld-runtime
          keld-update · keld-pack · keld-compat · keld-host (bin) · keld-cli (bin)
packages/ @keld/api · @keld/electron · @keld/web · @keld/cli · @keld/schema · create-keld   (upcoming)

Development

See AGENTS.md for engineering rules and verification gates.

cargo nextest run --workspace --profile ci
just hello    # macOS: open WKWebView hello window (Phase 1 slice)

License

MIT OR Apache-2.0 (see workspace Cargo.toml).