A multitrack recording, editing, mixing and mastering environment written in Rust — Linux first, Wayland native, GTK 4 native; Windows and macOS builds come from the same code.
FaderFrame aims to be a professional DAW: graph-based routing with buses, aux sends and sidechains, hard-realtime multicore audio processing with automatic plugin delay compensation, MIDI and virtual instruments, automation, CLAP/VST3 hosting, an analogue-console-style mixer, mastering meters and dockable, detachable editors.
Status: in active development. Most of a working DAW is there; see docs/ARCHITECTURE.md for what comes next.
The demo session playing — Mixing workspace:
The MIDI workspace with the piano roll editing the lead synth's melody:
The Mastering workspace with the Tools view (EBU R128 loudness, levels, phase and spectrum):
Seven skins, switched live (View → Theme or Preferences → General → Theme): Studio, Vintage Console (walnut cheeks, enamel panels, skirted knobs, plasma bar-graph meters), Daylight (light), Midnight, Frost, Neon and High Contrast:
- GTK 4 application, native on Wayland, HiDPI/fractional scaling via GTK.
- Arranger (virtualised): tracks, audio clips with waveforms, MIDI clips, move/split/delete, snapping, zoom down to single samples, loop range, playhead, console-style track headers with mute/solo/arm/monitor, volume, pan and meters. Clicking a clip selects it and moves the playhead to the (snapped) click; Shift- or Ctrl-click selects more clips, and moves, trims, fades and gain changes apply to every selected clip.
- Global lanes under the ruler (click a lane's title to show or hide lanes): markers (double-click to add, drag to move, double-click to rename, click to jump there), the arranger lane for song sections (drag to create Intro, Verse, Chorus …; resize, rename, recolour, loop or select a section), time signature changes and the tempo map (drag points up and down or sideways, type values, steps or ramps).
- Song arrangement with sections: drag a section to move it with its content — clips (split at its edges), automation, tempo and time signature changes, markers — and the song closes up and makes room around it; Ctrl-drag inserts a copy, Shift-drag moves only the section. The section menu duplicates a section, moves it earlier or later, or deletes it with its content. Each is one undo step.
- Track colours: click a track's colour stripe (arranger) or colour bar (mixer) for a colour chooser, or pick from the palette in the track menu.
- Pro-style editing, with an edit toolbar under the transport (Edit button or Ctrl+E; it wraps into as many rows as the window needs): edit modes Shuffle, Slip, Spot and Grid (absolute or relative); the Smart tool (upper half selects a range, lower half grabs, edges trim, top corners fade) plus Zoom, Trim and Time-Stretch Trim, Selector, Grabber and Separation Grabber, Scrubber and Pencil; grids from a bar down to 1/256 with triplet and dotted values; nudge values; Tab to clip boundaries or transients; Link Timeline and Edit Selection; Insertion Follows Playback; selection Start/End/Length counters in bars, time or samples; zoom buttons; a Follow button for scrolling along while playing. Range edits: separate, trim to selection, clear (Shuffle closes the gap), copy/cut/paste, duplicate, repeat, insert silence. The Scrubber plays the audio under the pointer while you drag; zoomed in to single samples, the Pencil redraws the waveform (click repair, on a copy — undo brings the original back).
- Clip gain: a gain knob in every audio clip's name strip (drag or turn the wheel; double-click resets, Alt-click types a value; Ctrl+Shift+↑/↓) and fades with five shapes (Linear, Equal Power, S-Curve, Fast, Slow) and a curve you bend by dragging its handle; right-click a fade to pick its shape.
- Transient detection (spectral flux, adjustable sensitivity, cached) and elastic audio: Warp view shows transients and warp markers — double-click adds a marker, dragging a transient moves just that hit (its neighbours stay pinned), dragging inside a selection warps only that range, Ctrl-drag telescopes; Separate at Transients and time-compression trims. Quantize (Q) and Humanize work on the selected clips, audio by its transients and MIDI by its notes alike: quantize strength and swing, note ends, humanize timing (ms) and velocity — set in the edit toolbar's Quantize menu or the piano roll's quantize settings. Warped clips play pitch-preserving (Polyphonic or Rhythmic, via Signalsmith Stretch) or as Varispeed.
- Transport: tap tempo (the TAP pad in the display), editable time signature (click it; right-click for common meters and meter changes), metronome button (K).
- Analogue-console mixer: inserts, sends (pre-FX / pre / post), pan, M/S/R, faders with a console fader law, segmented peak meters, routing menus, any number of sends per channel (rows grow, ◂ ▸ pages through banks), scribble strips, pinned master section; click a pan or level readout to type a value. The inserts section shows five slots by default; drag the grip on the rule below it for more or fewer (saved with the layout). Drag inserts to reorder them or onto another track to copy them with their settings (Ctrl copies within a track, Shift moves to another track); Alt-click removes one.
- Groups, VCAs and multi-track edits: with several tracks selected, moving a fader, pan or send moves all of them relatively (balances survive even pulling everything to −∞ and back), and mute, solo, arm, polarity, monitoring, colour, output and VCA are set on all of them. Track groups link volume, mute, solo, record arm and selection (each switchable, the group can be deactivated); VCA faders scale, mute and solo the tracks assigned to them, nested VCAs included, with automation. The mixer shows each strip's group and VCA.
- Sidechains: any plugin with a sidechain input can be keyed by another track (insert menu → Sidechain from …; the signal after its inserts, so a muted "ghost" track still keys); the built-in compressor has one.
- Freeze and bounce: Freeze Track renders a track after its inserts and plays the file instead (its plugins are unloaded until you unfreeze); Bounce to New Track puts the rendered audio on a new track.
- Piano roll: select/draw/erase/split/mute tools, rubber-band selection, moving and Alt-copying with snap (Shift: free), resizing from either edge, chords (fixed or scale-aware), scales with highlighting, snap and folding, quantize (strength, swing, ends), humanize, legato, reverse, invert, velocity stems and line ramps, controller lanes (mod wheel, pitch bend, sustain, any CC: freehand, lines, erase), ghost notes of the track's other clips, auditioning, step input from a MIDI keyboard, copy/paste/duplicate, clip-length handle, inspector with numeric entry, live keys on the keyboard.
- Docking: mixer / Tools / album / piano roll / automation / performance tabs in a bottom dock, detach any view into its own window and dock it back, workspaces (Recording, Editing, Mixing, MIDI, Mastering), layouts saved with the project. View → Master Strip at the Side keeps the master fader at the window's right edge, full height, whatever view is shown (per workspace; on in Mastering).
- Mastering meters (Tools, F12; the Mastering workspace opens on them): EBU R128 loudness — integrated, short-term and momentary, loudness range, true peak and PLR against a delivery target (−14, −16, −23, −24 or −9 LUFS) with a short-term history; peak/RMS levels in dBFS or K-12/14/20; goniometer and correlation; an FFT spectrum with peak hold — for the master or any track.
- Album (bottom dock, next to Tools): songs in release order — the project's sections, the whole project, other FaderFrame projects or finished mixes — with a pause or an equal-power crossfade, trim, fades, ISRC, credits and the song's own plugin inserts (heard on the master while editing) per song, and the release's title, credits and UPC/EAN; offline analysis (integrated loudness, range, true peak) and a preview of how each song will be delivered; export with one gain for the album (the songs keep their balance) or per-song levelling, true-peak limiting, dither, one file per song (cut gaplessly when songs crossfade), the whole album with a cue sheet and a CD master for replication: a DDP 2.00 fileset (44.1 kHz/16-bit, PQ codes, CD-Text, checksums) verified after writing.
- Engine: routing graph with cycle detection and plugin delay compensation, buses, auxes, sends, sidechains, solo-in-place, sample-accurate loops, built-in synth, echo, compressor, gain and latency-probe plugins, realtime-safe (verified by an allocation-counting test).
- Audio: native PipeWire (one node with a port per channel, linked to your
default devices), JACK (JACK2 or PipeWire-JACK), ALSA, WASAPI and ASIO
(Windows; ASIO in builds with the
asiofeature, see below), CoreAudio (macOS) and a silent dummy device; Automatic picks PipeWire, then JACK, then ALSA on Linux, and ASIO before WASAPI where it is built in. All common sample rates (44.1 – 192 kHz) and buffer sizes (16 – 8192 frames). - Audio import: WAV, AIFF, CAF, FLAC, MP3, Ogg Vorbis, AAC/M4A, ALAC — via
File → Import Audio (Ctrl+I) or drag & drop onto the arranger. Files are
converted to the project rate once and streamed from disk during playback
(bounded memory, lock-free read-ahead); media is kept in the project's
Audio/folder; missing files show as offline clips. - Recording: arm tracks, choose a mono input or a stereo pair per track, record with punch in/out, pre-roll and metronome; takes are latency compensated. Loop recording keeps every pass as a take. The record button (Shift+R) records and plays when stopped, punches in while playing and out while recording; with nothing armed a notice pops up. Warnings and errors pop up at the top of the window.
- Takes and comping: take folders with take lanes — click a lane to use a take, drag across it to comp a section, flatten when done. Record mode (keep as takes / replace) and loop-record mode (takes / last pass / new track per pass) are selectable in Transport and Preferences → Recording.
- Track presets: save a track's channel settings (format, input, plugins with state, fader, pan, sends, output, colour) and recall them as a new track or onto another track. Resizable tracks (drag a header's bottom edge, Alt+wheel for all, View → Track Height).
- Automation for every automatable parameter — volume, pan, mute, sends, plugin parameters and bypass: lanes under each track (A button / A key), point editing and freehand drawing with curve shapes, Read / Touch / Latch / Write modes; faders follow the automation while playing. The Automation tab in the bottom dock lists every lane of the project by track (modes, point counts, shown in the arranger or not; "+" adds a lane; all lanes to Read or Off at once) and edits the selected lane at full width over the whole song — add, drag and delete points, curve shapes, Write Value at the playhead or over the edit selection, Thin, Clear, Delete.
- Multicore engine: tracks, buses and plugins are processed in parallel on all cores (critical path first, realtime priority, flush-to-zero), with output bit-identical to single-threaded processing; Preferences → Audio → Processing threads.
- Render ahead (anticipative processing, on by default): tracks nobody plays live are rendered 200 ms ahead of the playhead on threads of their own, so heavy plugin chains need not finish within one tiny buffer — armed and live tracks, tracks with a plugin editor open, faders and sends stay immediate. With 64 tracks of six effects at 64-frame buffers the audio thread's worst callback went from 1.3 ms to 81 µs.
- Plugins: built-in synth/echo/compressor/gain, CLAP and VST3 effects and instruments on every platform and Audio Units on macOS, found by a crash-safe background scan (Audio Units: the system's registry) and picked in a plugin browser (click an empty insert slot or Track → Plugin Browser…). New instrument tracks start empty and open the browser to choose their instrument (an instrument picked for an empty instrument track's insert slot becomes its instrument); plugins that take notes in insert slots get the track's MIDI too. Click a filled insert slot for the plugin's own GUI (Ctrl-click bypasses, right-click for the parameter window, presets, sidechain and more); editors open centred or where they were last, and their positions are saved with the project. Plugin state, parameters and automation are saved too. Moving a knob in a plugin's own GUI writes automation like FaderFrame's controls do. Presets: save and load your own for any plugin (insert menu or the parameter window's Presets menu), and VST3 factory presets are listed too, as are VST3 program lists (selecting a program is one undo step; MIDI program changes select VST3 programs). Plugins that offer it can process in 64-bit floating point (Preferences → Audio). Sandboxing (Preferences → General, on by default): each CLAP and VST3 plugin (and Audio Unit on macOS) runs in a process of its own, so a plugin that crashes or hangs costs only itself — its track plays on dry, FaderFrame says so, and Reload Plugin (insert or instrument menu) starts it again with its recent settings. On Linux and Windows editors still open in FaderFrame's windows; on macOS, where a window cannot show another program's views, they open in a window of their own. Audio passes through shared memory (7–9 µs per plugin and block).
- MIDI files: File → Import MIDI File… (a track per MIDI track or channel, with controllers and SysEx; tempo and meter too when the project is empty) and File → Export MIDI File… (all MIDI tracks, or the selected clips).
- MIDI sync: follow an external MIDI clock (tempo too) or MIDI time code
(Preferences → MIDI → Sync). Per-note expression: pitch, pressure,
timbre, volume, pan, vibrato and expression per note — drawn in the piano
roll's expression lanes, recorded from MPE controllers, played natively
to plugin instruments (CLAP note expressions, VST3 note expression values
and poly pressure, the built-in synth) or as MPE on member channels
(track menu → MPE: pitch, pressure, timbre). SysEx is recorded,
sent to external devices and to the track's plugins with the clip (and
from a live keyboard to the instrument playing it), imported from and
sent as
.syxfiles. - MIDI keyboards and controllers: every MIDI input (ALSA sequencer incl. PipeWire, CoreMIDI, WinMM; hotplug) — instrument tracks play what you play while armed or selected, with constant low latency; choose the input and channel per track (track menu → MIDI In). Record MIDI into clips (takes or replace, loop recording). MIDI learn: right-click a fader, pan, mute, send, automation lane or plugin parameter → MIDI Learn and move a knob; pads can toggle switches or run transport functions; soft takeover and endless encoders (relative modes); mapped controls don't reach the instrument. Mod wheel, pitch bend, sustain and aftertouch are recorded into clips and chased on playback. MIDI tracks play external instruments (track menu → MIDI Out) in time with the audio, and MIDI clock can sync external gear. Inputs, outputs, clock and mappings in Preferences → MIDI.
- Performance meter (F8, or click the DSP readout in the status bar): total DSP load with a 60 s history and a breakdown into plugins, mixing and engine work; load per track and per plugin instance (average and peak, sortable, latency and bypass shown); xruns, late callbacks and late disk reads.
- Render / export to WAV (16/24-bit with TPDF or noise-shaped dither, 32-bit float): master or stems, project/loop/bar range, any sample rate, mono or stereo, tail, peak normalisation. Delivery: loudness normalisation to a target (BS.1770 integrated loudness) with a true-peak lookahead limiter, presets for streaming, Apple Music, CD, EBU R128 and ATSC A/85, and each written file's loudness, range and true peak.
- Preferences (start-up project, audio system, sample rate, buffer size,
live DSP statistics, editing defaults), undo/redo, versioned project
files (
.ffproj). A new start opens the last project, a new one or the demo session (Preferences → General;--empty/--demo/ a project path override it once); File → Open Recent lists the last ten projects.
Requirements: Rust 1.92 or newer (rustup) and GTK 4.14+ with pkg-config.
Linux additionally needs the development files of JACK (jack.pc;
libjack itself is loaded at run time, so FaderFrame starts without it),
ALSA and PipeWire, and libclang (the PipeWire bindings are generated at
build time):
| Distribution | Packages |
|---|---|
| Arch / Manjaro | gtk4 pkgconf pipewire-jack (or jack2) alsa-lib pipewire clang |
| Debian / Ubuntu (24.04+) | libgtk-4-dev pkg-config libjack-jackd2-dev libasound2-dev libpipewire-0.3-dev libclang-dev |
| Fedora | gtk4-devel pkgconf-pkg-config pipewire-jack-audio-connection-kit-devel alsa-lib-devel pipewire-devel clang-devel |
macOS (Apple Silicon or Intel): brew install gtk4 pkgconf.
Windows: in an MSYS2 UCRT64 shell,
pacman -S mingw-w64-ucrt-x86_64-gtk4 mingw-w64-ucrt-x86_64-pkgconf mingw-w64-ucrt-x86_64-gcc mingw-w64-ucrt-x86_64-rust.
Plugin GUIs embed natively everywhere: X11 windows on Linux (through XWayland), Win32 windows on Windows, Cocoa views on macOS. CI builds and tests all three platforms.
ASIO (Windows) is opt-in: cargo build --release --features faderframe-app/asio compiles Steinberg's ASIO SDK (downloaded by asio-sys,
or taken from CPAL_ASIO_DIR; bindgen needs LLVM — CI checks the backend
with the MSVC toolchain). The SDK's licence — Steinberg's proprietary one
or GPLv3 — then applies to that binary, which is why the default builds
leave it out.
cargo build --release
cargo run --release -p faderframe-app -- --demo # starts with the demo sessionThe binary is target/release/faderframe:
faderframe [--backend auto|pipewire|jack|system|asio|dummy] [--sample-rate HZ]
[--buffer-size FRAMES] [--threads N] [--empty | --demo]
[--import FILE]... [PROJECT.ffproj]
Without --empty, --demo or a project, FaderFrame opens what
Preferences → General → On start-up says (the last project by default).
system is ALSA, WASAPI or CoreAudio. JACK clients connect to the PipeWire
graph directly when pipewire-jack is installed; the native PipeWire
backend needs no JACK at all.
packaging/ builds installable packages; the Release workflow builds all
of them for a v* tag and attaches them to the GitHub release.
| Platform | Package | How |
|---|---|---|
| Linux | portable tarball (GTK bundled; runs in place, install.sh installs it) |
cargo build --release && packaging/linux/tarball.sh |
| Linux | Flatpak (GNOME 51 runtime) | flatpak-builder --user --install build-dir packaging/flatpak/io.github.BurningTreeC.FaderFrame.yml |
| Linux | system install from source (binary, desktop entry, AppStream, MIME type, icon) | cargo build --release && sudo packaging/linux/install.sh /usr/local |
| macOS | FaderFrame.app in a DMG (GTK bundled, ad-hoc signed) |
brew install gtk4 adwaita-icon-theme librsvg pkgconf && packaging/macos/bundle.sh |
| Windows | installer (Inno Setup) and portable zip | in MSYS2 UCRT64: packaging/windows/bundle.sh |
The macOS app is not notarised: open it the first time with right-click → Open.
Portable mode. With a folder named FaderFrame Data next to the
program, FaderFrame keeps everything it would put into your profile in
there — settings, plugin caches, presets, recordings of unsaved projects —
and also loads CLAP and VST3 plugins from its Plug-Ins/CLAP and
Plug-Ins/VST3. The Linux tarball and the Windows zip come with the
folder, so they run from a USB stick as they are; on macOS put the folder
next to FaderFrame.app (after moving the app out of the download
folder, which macOS runs from a read-only copy). Preferences → General
shows where the data goes.
| Key | Action |
|---|---|
| Space | Play / pause |
| Home | Return to start |
| L | Toggle loop |
| Shift+R | Record |
| Ctrl+P | Punch in/out |
| T | Show / hide the take lanes of the selected take folder |
| A | Show / hide automation of the selected tracks |
| Alt+wheel | Track height (all tracks) |
| Ctrl+Z / Ctrl+Shift+Z | Undo / redo |
| F2 / F3 / F4 | Toggle bottom dock / show mixer / show piano roll |
| F8 | Performance meter |
| F12 | Tools (loudness, level, phase, spectrum) |
| Ctrl+1 … Ctrl+5 | Workspaces |
| Ctrl+I | Import audio files |
| Ctrl+Shift+R | Render / export |
| Ctrl+, | Preferences |
| Ctrl+wheel / Shift+wheel | Zoom / scroll horizontally |
| Shift or Ctrl while dragging | Fine adjustment |
| Alt while dragging | Disable snapping |
| Ctrl+E | Show / hide the edit toolbar |
| K (or keypad 7) | Metronome on / off |
| Alt+1 … Alt+4 | Edit mode: Shuffle, Slip, Spot, Grid |
| Alt+S, F5–F7, F9, F10 (Alt+5 … Alt+0) | Smart, Zoom, Trim, Selector, Scrubber, Pencil (Grabber: Alt+8) |
| B | Separate clips at the selection (or the selected clips at the playhead) |
| Ctrl+C / Ctrl+X / Ctrl+V / Ctrl+D | Copy / cut / paste / duplicate the selection range |
| Alt+R | Repeat the selection range… |
| Ctrl+Alt+T | Trim clips to the selection |
| , / . | Nudge back / forward (Alt: trim start, Ctrl: trim end) |
| Tab / Shift+Tab | Next / previous clip boundary or transient (Ctrl: extend the selection) |
| Ctrl+Shift+↑ / ↓ | Clip gain ±0.5 dB |
| Ctrl+] / Ctrl+[ | Zoom in / out |
cargo fmt --all -- --check
cargo clippy --workspace --all-targets
cargo test --workspace # or: cargo nextest run --workspace
cargo run -p faderframe-bench --release -- --tracks 128 --block 64 --rate 96000
python3 scripts/third_party_licenses.py --check
cargo deny check licenses bans sourcesSee docs/ARCHITECTURE.md for the design, crate responsibilities and invariants.
FaderFrame is released under the MIT license. Third-party components and their licenses are listed in THIRD_PARTY_LICENSES.md.