Blokkily

Blokkily is an experimental pattern-based DAW. You can edit the same pattern in a tracker, piano roll or step grid, then arrange patterns across multiple tracks. It supports CLAP and VST3 plugins, SoundFont instruments and built-in samplers. CLAP support is required in every build.

Watch a short video (with sound) of an agent building a funky chiptune in Blokkily over MCP, using the YANES and FUZZBOI CLAP synths.

The screenshot comes from the bdd_session_everything verification session. It shows an eight-track arrangement with a tempo ramp and warped and recorded audio clips, the step grid, tracker and piano roll, the sampler, the plugin browser and the mixer, with the composition assistant's prompt bar above the editors.

Download

Each release carries packages built and tested by CI:

• Linux: blokkily-<version>-Linux.tar.gz (or .tar.xz), built on Arch Linux. It expects Qt 6, FluidSynth, RtAudio, RtMidi, JACK, libsndfile, libsamplerate and Rubber Band from the system.
• Windows: blokkily-<version>-Windows-x64-setup.exe, an installer with a Start-menu entry and an uninstaller, or blokkily-<version>-Windows-x64.zip to unzip anywhere and run bin\blokkily.exe.
• macOS: blokkily-<version>-macOS-arm64.dmg for Apple Silicon, or blokkily-<version>-macOS-x86_64.dmg for Intel Macs, each a self-contained Blokkily.app. It is signed ad hoc, not notarized, so macOS blocks the first launch. Either Control-click the app and choose Open, or run xattr -dr com.apple.quarantine /Applications/Blokkily.app.

SHA256SUMS lists every package's checksum.

To make a self-contained Linux package, packaging/appimage/build-appimage.sh turns a Release build into an AppImage, and packaging/flatpak/dev.blokkily.Blokkily.json builds a Flatpak with flatpak-builder. See usage.

Plugin editors work in every package. CI opens the suite's test CLAP and VST3 editors, and the editors of a real third-party synth (Dexed), in a real window on macOS and Windows and reads their pixels back. Retina and high-DPI scaling have not been checked there yet.

Build and run

You need CMake 3.25+, Qt 6.5+ with its Linguist tools (qt6-tools), plus FluidSynth, RtAudio, RtMidi, libsndfile, libsamplerate and Rubber Band 4 (found through pkg-config), and on Linux libjack (JACK or PipeWire's JACK). JUCE and the CLAP headers are vendored under third_party/, so clone with --recursive.

The verification tests need a SoundFont. CMake looks for basic.sf2, TimGM6mb.sf2 or FluidR3_GM.sf2 in /usr/share/fweelin, /usr/share/sounds/sf2 and /usr/share/soundfonts; otherwise pass -DBLOKKILY_TEST_SF2=/path/to/bank.sf2. They also need ffmpeg on PATH to check the scope video export, and configuring fails without it.

cmake -S . -B build -G Ninja
cmake --build build
ctest --test-dir build --output-on-failure
./build/blokkily

./build/blokkily_cli runs the headless scheduler demo.

Linux is the primary platform. macOS builds with Homebrew's Qt and libraries, and Windows builds with MSVC, vcpkg and the official Qt binaries. The CI workflows in .github/workflows/ (platforms.yml and release.yml) show the exact commands for each.

Clip warping links the Rubber Band Library, licensed under the GPL (version 2 or later) unless you buy a commercial licence from its authors. A Blokkily binary built with it is therefore subject to the GPL.

IBM Plex Sans and JetBrains Mono are bundled in resources/fonts/ under the SIL Open Font License 1.1, with licence texts beside them. Bundling the fonts keeps the layout consistent across desktops.

What you can do

• Edit notes and chords in any of the three synchronized editors. Patterns support inversions, strum, swing, microtiming, probability, ratchets, loop conditions and parameter locks, which can also move an insert on a return or the master bus. Edits are heard during playback without stopping it.

• Arrange named patterns and audio clips on a multi-track timeline, with tempo steps, ramps and meter changes. LOOP wraps playback between IN and OUT on the arrangement; an export still writes the whole song. The scene launcher lets you perform patterns live, give a scene its own tempo, and record the performance into the arrangement.

• Play and record with a MIDI controller or the on-screen piano, isomorphic grids, fretboards and chord pads. Tunings and scales include microtonal options. A session with no instruments uses an installed SoundFont by default, preferring a General MIDI bank when available.

• Load CLAP, VST3, LV2 and SoundFont instruments, or use the keyed and drum samplers. CLAP and VST3 plugins open their own editors, embedded in a Blokkily window on Linux, macOS and Windows.

• Mix with inserts (including built-in EQ, delay, reverb, compressor, true-peak limiter, resonant filter, saturation, chorus, flanger and gate), sends, returns, sidechains, auxiliary outputs, automation and modulation. Plugin latency is compensated in playback and export.

• On Linux, play through ALSA, PulseAudio or JACK. Blokkily drives JACK (and PipeWire's JACK) directly, at whatever block size the server runs. See audio system.

• Warp audio clips to follow the tempo, or stretch and pitch-shift them.

• Play hardware synths and drum machines from a track through a MIDI output, and send them MIDI clock, or follow another machine's clock.

• Record audio and MIDI (including MPE and poly pressure), with a metronome and count-in. Resample a bus or bounce stems. Export the arrangement as 16-bit, 24-bit or 32-bit float WAVE, MP3 or Ogg Vorbis through the same engine used for playback, every track as a file of its own (STEMS), or an oscilloscope video of every track over the master (SCOPE VIDEO, encoded by ffmpeg on PATH). Import and export Standard MIDI Files for note exchange, and export the whole song (mixer, automation, plugin states, audio) as a DAWproject for Bitwig Studio, Studio One or Cubase.

• Save named versions of the song and restore any of them in one undo step, and keep notes with it, in the VERSIONS and NOTES tabs.

• Read any part as staff notation in the SCORE view: all eleven clefs from French violin to percussion, any key, any meter or unmetered chant, chords, voices, ties, accidentals and lyrics in any script, with the clef, key and meter saved with the song. Write notes straight onto the staff with the mouse and arrow keys. Bring a hymn or a choral score in from notation software with SCORE IN, and send the song out with SCORE OUT, as MusicXML.

  

  The screenshot comes from the bdd_score_file verification session: a MusicXML hymn brought in with SCORE IN, its Hebrew lyrics drawn under the notes, as voice and organ tracks in the arrangement above.

• Press F1 or HELP for a guided tour of the window. CLEAR empties the session in one undo step.

• Press GUIDE for a mascot that narrates what you and your agent do and why, answers theory questions and teaches short interactive lessons.

• Ask the LLM composition assistant for a phrase. Review its proposal before applying it; each generation is one undo step. An MCP bridge also lets agents control the running application and measure what they render (loudness, true peak, band energy).

See the usage guide for controls, keyboard shortcuts and recording workflows.

Current limitations

Blokkily is experimental. MPE support varies by instrument format. Large unwarped audio clips can stream from disk; warped clips and sampler samples still load into memory. On Linux, plugin editor windows need X11, or Wayland with XWayland or a CLAP plugin's own Wayland support. Export always renders the arrangement, so record a launcher performance into it before exporting.

The limitations reference covers these restrictions and others, including sidechains, modulation timing, sampler editing and stems.

Documentation and development

• Usage guide: editing, arranging, recording, mixing and shortcuts.
• Architecture: the shared model, scheduler, plugin adapters and coverage commands.
• Agent control through MCP: setup, tools and environment variables.
• LLM composition assistant: backends and reply format.
• Verification: repeatable BDD, integration, end-to-end and screenshot checks.

Behaviour specifications live in features/. Repository-wide completion rules are in AGENTS.md.