Kerchunk

Kerchunk is a native, cross-platform desktop client for operating a full AllStarLink-style node without radio hardware, a Pi, or a VM. It is built with Electron and TypeScript and targets Windows, Linux, and macOS.

The project is independent and is not affiliated with or endorsed by AllStarLink, Inc.

Copyright © 2026 W9MDM. Released under the PolyForm Noncommercial License 1.0.0 — free to use, modify, and share for any noncommercial purpose; selling it is not permitted.

Install (Windows)

Grab a build from the release/ folder (or from whoever sent it to you):

• Kerchunk-x.y.z-Setup.exe — installer. Run it, pick a folder, and it adds Start Menu and desktop shortcuts.
• Kerchunk-x.y.z-Portable.exe — no install; double-click to run.

These builds are not code-signed, so Windows SmartScreen will show a "Windows protected your PC" prompt the first time. Click More info → Run anyway. Kerchunk only makes outbound connections (AllStarLink DNS, registration/portal HTTPS, and IAX2 on UDP 4569) — no inbound ports needed.

Two ways to connect

• Node mode — for operators with an issued AllStarLink node number. Enter your node number and secret, Register, then link to any node.
• Web Transceiver — for anyone with a callsign and a free allstarlink.org portal account, no node number required. Enter your callsign and portal password; Kerchunk fetches a per-node session token from the portal and connects as a guest.

The Node / Web TX choice, like the rest of your settings, is remembered across restarts.

Features

• First-run setup wizard — a step-by-step walkthrough on first launch (mode → credentials → audio) so you're on the air in a minute. Re-runnable any time from the menu.

• Node directory (📡 button by the gear) — searches the full AllStarLink node database, grouped by country and US state, so you can find and one-click link a node without knowing its number. Saving a node keeps its callsign, description, and location.

• Favorites / saved nodes — a quick-pick dropdown and an editable list in Settings, with live "keyed" coloring polled from the AllStarLink stats API so you can see which of your favorites are active. A Save button keeps a node deliberately (connecting only adds to Recent, so the saved list stays yours).

• Recent nodes — the last several nodes you connected to, one click to relink.

• MDC1200 PTT-ID — clean-room encoder that sends your unit ID over the air on key-up/key-down (confirmed decoding on app_rpt), with a local Motorola-style talk-permit tone and adjustable level/preamble.

• DTMF commands — a keypad and free-form sender for app_rpt * commands, plus saved commands you can name and re-send with one tap.

• Announcements — optional spoken and/or desktop-notification alerts for connect / disconnect / call-failed events (off by default; Settings → Audio).

• Push-to-talk — on-screen hold-to-talk, a global PTT hotkey that supports multi-key combos (e.g. Ctrl+Shift+T), and a floating PTT overlay — a small always-on-top button that hovers over any other application (toggle it from the menu; drag it anywhere).

• Audio device selection & levels — pick your microphone and speaker and set input/output levels in Settings → Audio, plus a speaker button in the header for quick app-volume control.

• Network topology — a live tree of the mesh you're linked into.

• Collapsible sections — every panel minimizes (state remembered); the Transmit panel keeps a compact PTT button even when collapsed.

• Auto-update — checks GitHub Releases on launch (and on demand from the menu), shows the changelog, and can download + install the update in place (NSIS installer and AppImage; Portable/.deb get a download link instead).

• In-app menu — a Font Awesome menu (directory, register, refresh, disconnect all, advanced mode, check for updates, settings, about).

• Runs in the background — optional system-tray icon with close-to-tray and launch-at-startup (Settings → General).

• Backup / migrate — export and import your settings and saved nodes as JSON (Settings → General).

• Advanced mode — reveals direct-address linking and custom IAX link credentials for private nodes/hubs (off by default).

• Tabbed Settings — Node, Saved nodes, Hotkey, Audio, MDC1200, and Appearance; everything persists, including the window size and Node/Web-TX mode.

Node and Web Transceiver modes each unlock only once their credentials are set, so you can't accidentally pick a mode you can't use.

Why Kerchunk exists

The original AllCall concept aimed to give users a practical way to participate in AllStarLink-style linking from a desktop environment. Kerchunk carries that idea forward with a modern desktop application that keeps the node experience local, focused, and testable.

Current status

• The Electron shell (main, preload, renderer) and the theme bridge are in place.
• Kerchunk is a self-contained node: it implements in-app what Asterisk + chan_iax2 + app_rpt do. KerchunkNode owns one UDP socket, demultiplexes incoming frames to per-peer call legs by call number, and runs an app_rpt-style conference bridge (N-1 mixing) so every linked node plus the local port (the operator's mic) hears everyone but itself.
• A pure-TypeScript IAX2 protocol engine underneath: full/mini frame codecs, RFC 5456-compliant information elements (correct type numbers and field widths, so it interoperates with real Asterisk peers), a guarded call-control state machine, call-time and registration MD5 authentication, and voice/DTMF/text handling. No Electron dependency; exercised entirely from Node tests.
• Node-number linking over AllStarLink DNS (nodes.allstarlink.org SRV/A/TXT): link to a node by number, or to a direct address (a node/hub you run). Outbound linking only for now; the socket is structured so accepting inbound is a later toggle. Outbound calls that go unanswered time out after 15 s (instead of hanging in "calling" forever) and announce the failure.
• ASL3 HTTP registration (register.allstarlink.org) with automatic refresh, so the node publishes its number → public IP and other nodes accept its links.
• Standard ITU-T G.711 µ-law/A-law codecs, wire-compatible with Asterisk.
• A renderer audio path: AudioWorklet microphone capture framed to 8 kHz / 20 ms frames, G.711 encoding over the IPC bridge, push-to-talk gating, and scheduled playback of the node's mixed RX audio.
• The desktop UI exposes node identity, link-by-number (or address), a live connected-nodes list with per-link disconnect, drop-all, and push-to-talk, plus TX/RX level meters and an activity log. Icons throughout are Font Awesome (bundled inline; no webfont fetch), with tooltips and screen-reader labels on icon-only controls.
• Vitest covers the codecs, frame wire format, IE handling, the call state machine, the framing helper, DNS resolution, the conference mixer, the call leg, and the node end-to-end (bidirectional conference over real UDP).

Build from source

Requires Node.js 20+ and npm.

npm install
npm run dev          # run in development
npm run dist:win     # build the Windows installer + portable .exe → release/
npm run dist:mac     # macOS .dmg (must run on macOS)
npm run dist:linux   # Linux build (packaged as a tarball; see note below)
npm test             # run the Vitest suite

Build artifacts land in release/. The app icon is generated into build/icon.png and electron-builder derives the per-platform icons from it.

Linux packaging note: the .deb can't be assembled on Windows (mksquashfs isn't available), so a local Windows workflow ships Linux as a Kerchunk-x.y.z-linux-x64.tar.gz tarball built from release/linux-unpacked (with a run.sh launcher). CI builds the native .deb on Linux. (The AppImage target was dropped: at ~112 MB it exceeded the 100 MB upload cap of the Cloudflare proxy in front of the Gitea release host.)

Documentation

• docs/ARCHITECTURE.md — process layout, IPC boundaries, protocol engine, audio path.
• docs/IAX2.md — notes on the IAX2 protocol as implemented.
• docs/PROTOCOL-INVARIANTS.md — live-verified protocol behaviors that must not change without live-node testing.
• docs/DEVELOPMENT.md — building, testing, packaging, release/download stats.
• docs/PRESENTATION.md — slide-deck content & design brief for presenting Kerchunk.

Roadmap

1. Inbound-link support (accept NEW; UDP 4569 forwarding / reachability check).
2. Reliable delivery for full frames (retransmission, sequence recovery).
3. Remaining app_rpt niceties: courtesy tones, CW/voice node ID.
4. Full 32-bit format negotiation and codec fallback beyond G.711.
5. Code-signing for signed, SmartScreen-clean installers.

License

Kerchunk is copyright © 2026 W9MDM and released under the PolyForm Noncommercial License 1.0.0: you may use, modify, and share it for any noncommercial purpose, but you may not sell it or use it commercially. See LICENSE for the full text and THIRD-PARTY-NOTICES.md for the open-source components it builds on (which keep their own permissive licenses).