Lockstep

Lockstep is a performance-oriented step sequencer that runs as a plugin inside your DAW or as a standalone application. It is a VST3, a CLAP, a standalone app, and an AU on macOS.

It is a sequencer you play, not one you configure. Trigs, conditional logic and per-step parameter locks replace the click-and-drag automation of a traditional DAW, and the entire editing workflow is reachable from the computer keyboard — no mouse required.

Three influences are explicit in the design:

• Digitakt — the feel of the core: the trig grid, P-Locks, trig conditions, fills, performance mutes, and the "control-all" gesture that broadcasts one parameter edit across every track at once.
• Octatrack — the project hierarchy, and the idea that every track chooses its own sound engine. A track can host a sampler, a synth, or a MIDI-out adapter, and the sequencer treats them identically.
• Squarp Pyramid — external gear as a first-class citizen rather than an afterthought.

One rule shapes more of the design than any other: every key earns its place in a small scope + verb grammar, and adding a bespoke single-purpose button is forbidden. If a feature would need its own key, it is not ready.

Status: pre-beta, and honest about it

Lockstep is not released yet. There are no downloadable builds — you build it from source today. See Installing.

Platform support, stated precisely, because "it compiles" and "it works" are different claims:

Platform	State
Linux	Built, tested and used. This is where every line was written.
macOS	Compiles and passes the full test suite in CI. Never loaded in a host. No window has been opened, no audio device opened, and the AU has never been through auval.
Windows	Compiles under MSVC and passes the vendored test suites. Its two GUI-dependent suites are excluded in CI because a Windows runner has no interactive desktop session, so they are unrun rather than passing.

macOS and Windows were first compiled on 2026-10-04 and are marked experimental in CI for exactly these reasons. If you run Lockstep on either, a report of what happened is the single most useful contribution the project can receive — see CONTRIBUTING.md.

Where to go next

• Installing — building from source, and what each platform is actually known to do.
• Tutorial — your first piece of music.
• The paradigm — how to reason about the system. Worth reading before the reference; most confusion about Lockstep is a paradigm mismatch rather than a missing feature.
• Feature reference and Gesture tree — the complete surface, every action by press order.
• Implemented vs. planned — what exists today, stated honestly against what is designed.

Licence

Lockstep is free software under the GPLv3. Its dependencies and their obligations are recorded in THIRDPARTY.md.