v.4.0.0

A ground-up rebuild of how FileSync connects and saves files — native WebRTC, a built-in signaling server, and true streaming-to-disk for transfers of any size.

This is a major release. FileSync no longer depends on PeerJS: connection setup is now handled by a lightweight first-party signaling server bundled with the app, and received files stream straight to disk so even multi-gigabyte transfers stay memory-safe.

Important

Upgrading from 3.x requires re-downloading the compose files (docker-compose.yml, and for HTTPS the docker-compose-ssl.yml + Caddyfile). Pulling the new image alone is not enough — see Upgrading.

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✨ Highlights

• 🔗 Native WebRTC — PeerJS is gone. Smaller footprint, fewer moving parts, no third-party connection broker.
• 📡 Built-in signaling server — served by FileSync itself at /ws. Nothing extra to run; it relays only connection setup and never sees your files.
• 💾 Streaming downloads, any size — files are written to disk as they arrive, so memory stays flat even on multi-GB transfers.
• 🩺 Redesigned diagnostics page at /test.html — light/dark, an at-a-glance verdict, and a one-click connectivity report to share with support.
• 🛡️ Hardened for production — required secret at startup, rate-limited credentials, a self-healing container, and self-hosted fonts.

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🚀 What's new

Connectivity

• Native RTCPeerConnection / RTCDataChannel client replacing the PeerJS wrapper.
• First-party WebSocket signaling relay (/ws) with rate limiting, idle timeouts, and capacity guards.
• Relayed transfers now work correctly behind Docker — TURN relay candidates are rewritten in transit so peers on different networks get a reachable address.

Transfers

• Chunked, backpressured protocol that keeps both sender and receiver memory bounded.
• Three save methods, auto-selected per browser:

  Method	When	Notes
  File System Access	Desktop Chrome/Edge/Brave/Opera (HTTPS)	Streams straight to a file you pick
  Service Worker	All modern browsers (HTTPS)	Streamed browser download, memory-safe
  Blob	Fallback / plain HTTP	Buffered in memory (~500 MB practical limit)

Reliability

• Serialized disk writes — fixes a File System Access corruption case on fast/large transfers.
• Transfers no longer hang if a peer drops mid-send; abort, remove, and "cancel all" now tear down cleanly (no leaked connections or stuck downloads).
• Transient network blips are tolerated instead of killing an in-progress transfer.
• The container self-heals: if the backend process dies, it restarts instead of serving a half-dead app.

Security

• The server refuses to start without SECRET_KEY (used to sign TURN credentials and tokens).
• /api/credentials is rate-limited; CORS is off by default (opt-in via CORS_ORIGINS).
• Fonts are self-hosted — no third-party font CDN, satisfying the app's strict Content-Security-Policy.

Tooling & docs

• End-to-end Playwright test harness covering browsers × save methods × connection modes.
• Dependabot for Python, Docker, GitHub Actions, and the test harness.
• README refreshed: how connections are made, the required ports, and how files are saved.

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⚠️ Upgrading from 3.x

The compose files changed — re-download them.

1. Re-download the deploy file(s) for your setup:

   • HTTP → deploy/docker-compose.yml
   • HTTPS → deploy/docker-compose-ssl.yml + deploy/Caddyfile

2. Set your secret (now required — the app won't start without it). Generate one:

   python3 -c "import secrets, base64; print(base64.b64encode(secrets.token_bytes(32)).decode())"

   Replace both <SECRET_KEY> placeholders in the compose file.

3. Open the required ports (below) if you haven't already.

4. Pull and restart:

   docker compose pull && docker compose up -d

💡 No separate PeerJS server is needed anymore — if you ran one, you can decommission it.

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📋 Required ports

Port	Protocol	Purpose
80 / 443	TCP	Web interface (HTTP / HTTPS)
3478	TCP + UDP	STUN/TURN — connection setup
50000–50100	UDP	TURN relay range (used when a direct path isn't possible)

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Full changelog: v.3.7.0...v.4.0.0

v.3.7.0

Changes:

• WebRTC compatibility check — Added a browser compatibility check that detects if RTCPeerConnection is unavailable and displays a user-friendly error message with a link to supported browsers, preventing the app from crashing on incompatible browsers.

v.3.6.0

Changes:

• Version badge in title — The app version is now displayed as a pill badge next to the "FileSync" heading, fetched dynamically from the API.

v.3.5.0

Automatic reconnection with exponential backoff

This release improves connection resilience by automatically reconnecting to the PeerJS signaling server when the connection drops, instead of immediately showing an error.

What's new:

• Auto-reconnect for user peers — When the signaling server connection is lost, FileSync now schedules up to 5 reconnection attempts with exponential backoff (1s → 2s → 4s → 8s → 16s). If all attempts fail, a clear error message is shown asking the user to refresh.
• Auto-reconnect for file transfer peers — File-transfer peers independently retry up to 3 times with the same backoff strategy, preventing interrupted transfers from silently failing.
• Smarter error handling — Peer errors are now classified into:
  • Fatal (browser-incompatible, invalid-id, unavailable-id, ssl-unavailable) → immediate error page.
  • Recoverable (disconnected, network, server-error, socket-error, socket-closed) → triggers reconnect.
  • Expected (peer-unavailable) → logged as a warning, no disruption.

v.3.4.0

Changes:

UI Redesign

• New design system with Inter font, refined spacing, shadows, and animations
• Modernized cards, buttons, modals, tables, and form elements across light/dark themes

Toast Notifications

• Replaced modal notifications with lightweight slide-in toasts
• Contextual feedback for all user actions (file ops, user joins/leaves, clipboard, password, name changes)

File Sharing

• Drag-and-drop file uploads with visual drop-zone feedback
• Duplicate file detection to prevent re-sharing identical files
• Redesigned file details modal with inline progress bars and status badges

Docker

• Upgraded Python 3.12 → 3.14
• Added container HEALTHCHECK
• Path-agnostic site-packages cleanup

v.3.3.0

Changes:

• The default HTTP port (80) is now configurable.
• Replaced the deprecated crypto-js library with the modern Web Crypto API.
• Improved the README.md for better clarity and easier setup instructions.

v.3.2.0

• Deploying FileSync is now simpler. Port 9000 no longer needs to be exposed, as FileSync can connect to the PeerJS server internally.

⚠️ Important

Make sure to re-download the docker-compose.yml and Caddyfile from the deployment folder, as this Release includes important changes.

v.3.1.0

• Fixed a Chrome compatibility issue transferring files.
• Bootstrap is now bundled directly in the project.
• Added a new page (test.html) to test ICE server connectivity (STUN and TURN).

v.3.0.0

• Full rework of core functionality.
• Numerous bug fixes and performance improvements.
• Added Docker Compose support for easy self-hosted deployment.

v.2.3.0

This update introduces a custom TURN server to enhance the reliability of connections behind NATs.