libtorrent_flutter 1.6.3

Native libtorrent 2.0 bindings for Flutter with a built-in HTTP streaming server for instant torrent video playback. Supports Windows, Linux, macOS, iOS, and Android.

Changelog

1.6.3

• Streaming: Instant start — staggered piece deadlines (0ms, 500ms, 1000ms…) on startup instead of flat 0ms for all. libtorrent's time-critical picker now funnels all bandwidth to piece 0 first, so playback can begin as soon as 1 piece arrives instead of waiting for 8
• Streaming: Shrunk critical window from 6 pieces → 2, hot window from 9 → 5, readahead from 15 → 6 — concentrates bandwidth on the most urgent data per libtorrent's streaming docs: "any block you request that is not urgent takes away bandwidth from urgent pieces"
• Streaming: Buffer percentage now based on the 2-piece critical window — reports "ready" faster since it no longer waits for 6 pieces
• Seeking: Tighter seek focus — 2 pieces at staggered near-zero deadlines + 2 more at 200ms stagger (was 4 all at 0ms), reducing bandwidth dilution on seek
• Seeking: Seek cooldown reduced from 1000ms → 100ms — priority loop resumes almost immediately after a seek instead of staying blind for a full second
• Seeking: Wait timeout reduced from 120s → 30s — fails faster on dead peers instead of hanging
• Performance: Priority loop now runs every 100ms (was 200ms) for faster reaction to playback position changes
• Performance: libtorrent tick_interval set to 100ms (was 500ms default) — internal scheduler reacts 5x faster to deadline changes and priority updates
• Serve: Inline lookahead reduced from 5 → 3 pieces with 100ms stagger (was 10ms) — less bandwidth competition with the current piece

1.6.2

• CRITICAL FIX: Removed force_recheck() from cache eviction — it was re-hashing the ENTIRE torrent, marking ALL pieces (including currently streaming ones) as unknown, killing the stream
• Streaming: Capped readahead window to 50% of cache capacity — prevents downloading so far ahead that the cache overflows and evicts data at the current playback position
• Streaming: Hard safety floor — cache eviction NEVER evicts anything within 5 pieces of the current playhead, regardless of cache pressure

1.6.1

• Streaming: Fixed serial pipeline stall after seek — serve_range now pre-primes the next 5 pieces with priority 7 and staggered deadlines before each wait_for_piece call, so the swarm downloads them in parallel instead of one at a time
• Streaming: Reduced seek cooldown from 3s → 1s — the new serve_range lookahead covers the gap, so the priority loop can resume sooner and set broader readahead windows

1.6.0

• Streaming: Rewrote priority system using torrest-cpp's proven priority-only-upgrade pattern — never downgrade piece priorities, staggered i*10ms deadlines for the hot window
• Streaming: Increased critical window from 3 → 5 pieces at deadline=0ms for faster initial playback
• Streaming: Total seek focus — on seek, all piece priorities are wiped and ONLY the seek position + 3 pieces get deadline=0ms with a 3-second cooldown before the priority loop resumes
• Streaming: wait_for_piece timeout increased from 15s → 120s to prevent "Stream ends prematurely" errors during slow torrent startup
• Streaming: Reduced readahead buffer from 30 → 15 pieces to concentrate bandwidth closer to the playhead
• Engine: Added no_recheck_incomplete_resume — skips file recheck on resume for faster startup
• Engine: Added allow_multiple_connections_per_ip — connects to seedboxes, VPNs, and shared NAT peers
• Engine: Added peer_connect_timeout=3s for faster peer handshakes
• Engine: Tuned timeouts to stop peer churn (piece_timeout 2→5s, request_timeout 2→4s, peer_timeout 5→10s) — proven by libtorrent issue #7666, torrest, and Elementum
• Engine: whole_pieces_threshold increased 5 → 20, forcing fast peers to complete whole pieces instead of scattering blocks

1.5.0

• Streaming: Removed speculative tail preloading — the engine no longer downloads the last 4MB of a file at startup. Modern players (MPV, VLC, etc.) fetch container metadata (MP4 moov atom, MKV cues) on-demand via HTTP range requests, which the built-in server already supports
• Streaming: Head-only preload now sets 8 pieces at flat deadline=0ms instead of staggered 30ms intervals, focusing 100% of startup bandwidth on the beginning of the file
• Streaming: Removed file anchor logic from the priority loop that re-prioritized the last 2 pieces every 200ms, which competed with the playhead for bandwidth
• Performance: Startup time reduced from ~30–60s to ~5–15s by eliminating bandwidth competition between head and tail piece downloads

1.4.0

• Platform: Added iOS support

1.3.0

• Platform: Added iOS support (arm64 device + x86_64 simulator, universal static library)
• CI: New build-ios job cross-compiles libtorrent + torrent_bridge as a static .a for iOS, merged with lipo
• Packaging: iOS podspec with -force_load so all FFI symbols are visible via DynamicLibrary.process()

1.2.0

• License: Switched to GPL v3 (OSI-approved)
• Streaming: Dual-end preloading — fetches first 4MB and last 4MB of the file simultaneously on stream start. The tail contains the MP4/MKV moov atom (seek table), enabling instant seeking without buffering the whole file first
• Streaming: Staggered 30ms piece deadlines on the head (down from 45ms) for faster playback start
• API: disposeTorrent(id) — stop streams, remove torrent, and delete files in one call
• API: disposeAll() — clean up every torrent and stream at once (ideal for exit button)
• API: startStream() now accepts maxCacheBytes for a sliding window RAM cache limit
• API: init() now accepts defaultSavePath (defaults to system temp dir — no permission setup needed)
• API: addMagnet() and addTorrentFile() savePath is now optional (uses defaultSavePath)
• README: Fully rewritten with complete API documentation and code examples

1.1.0

• Streaming: Removed sequential_download flag (conflicts with set_piece_deadline)
• Streaming: Reduced readahead from 150 to 30 pieces to avoid excessive pre-buffering
• Streaming: clear_piece_deadlines() on seek + 1-second cooldown for faster seek response
• Streaming: Re-enabled uTP for incoming and outgoing connections (reaches more peers behind NAT)
• Cache: Configurable RAM cache limit with percentage-based sliding window eviction (10% safety buffer, min 5 pieces)
• Save path: Defaults to system temp directory on all platforms
• CI: Automatic GitHub Release creation with zipped native libraries on every build
• pubspec: Added repository, issue_tracker, and topics fields for pub.dev discoverability

1.0.0

• Initial release
• Native libtorrent 2.0 bindings via Dart FFI
• Built-in HTTP streaming server with byte-range support
• Windows, Linux, macOS, and Android support with prebuilt binaries (no build required)
• Auto-fetches best public trackers on startup
• Magnet link and .torrent file support
• Per-file streaming with automatic largest-file selection
• torrentUpdates and streamUpdates streams for reactive UI
• DHT, PEX, LSD peer discovery