go-sequence

MIDI sequencer/arranger. Not a DAW. A MIDI brain.

Status

Working: Drum sequencer (16 sounds, 32 steps, variable length), piano roll (note editing, playback), clip launcher, Launchpad X with LED feedback. Track-based architecture with per-track MIDI channels.

Feature Checklist

Universal

• Pattern selection per device (</> to switch editing pattern)
• Device reports pattern content (empty vs has data) for clip launcher display
• Undo/redo
• Multiple Launchpads (independent navigation)

UI

• Mini Launchpad in TUI (with color zones)
• Pattern select on Launchpad (all devices)

Session Device (clip launcher)

• Launch patterns on devices
• Show playing vs queued
• Show empty vs has-content patterns
• Track-based with MIDI channel per track
• UI to change track channel/device/output (Settings device, press ,)
• Scene launch (whole row at once)
• Stop clip on device

Drum Device

• Toggle steps
• Basic playback
• 1-32 steps per track (variable length, [/] to adjust)
• 16 sounds/notes per pattern
• Drum kit mapping (GM, RD-8, TR-8S, ER-1) - patterns store slot indices, kit maps to MIDI notes
• Velocity per step (data exists, no per-step UI yet)
• Clear track (c) / clear pattern (C)
• Launchpad layout (top: steps, bottom-left: track select, bottom-right: commands)
• Preview mode - audition sounds from track pads
• Record mode - record steps from MIDI input
• Nudge notes forward/backward (data structure exists)
• Copy/paste pattern

Piano Roll Device

The piano roll is for editing notes you play in via MIDI keyboard - not for composing from scratch. Quick fixes: nudge timing, fix wrong notes, adjust velocity/length.

• Playback note events with timing and note-off
• Viewport-based rendering (center follows selection)
• Select notes with hjkl, move with yuio (no mode toggle)
• Note length with n/m
• Add/delete notes (space/x)
• Pattern length ([/])
• Horizontal zoom (8 levels, q/w)
• Vertical zoom (smushed/spread, a/s)
• Edit sensitivity (coarse/fine, d/f horiz, e/r vert)
• Overlap visualization (overlapping notes shown with ═)
• Record from MIDI keyboard ← priority
• Quantize

Metropolix Device

• Stages with pitch, gate, probability
• Ratchets
• Slides
• Accumulators

Transport

• Play/stop
• Tempo control
• Tap tempo

MIDI

• Note-off tracking (piano roll tracks held notes)
• Per-track MIDI channel output
• Multiple MIDI output ports (per-track routing in Settings)
• Channel mapping UI (Settings device)

Save/Load

• Project folders with timestamped saves (~/.config/go-sequence/projects/)
• Quick save (Shift+S)
• Save device for browsing/loading (Shift+D)
• Create/rename/delete projects and saves

Controls

Global

• Q - quit (Shift+Q)
• P - play/stop (Shift+P)
• +/- - tempo ±5 BPM
• S - quick save to current project (Shift+S)
• D - focus save device (Shift+D)
• 0 - focus session (clip launcher)
• 1-8 - focus device by track number
• , - focus settings

Drum Device

• h/l - cursor left/right
• j/k - select track up/down
• space - toggle step
• [/] - track length -/+
• c - clear track
• </> - previous/next pattern (editing)

Launchpad commands (bottom-right 4x4):

• Preview toggle - audition sounds when tapping track pads
• Record toggle - write steps when tapping track pads during playback
• Clear track/pattern, length +/-

Piano Roll

Select notes

• hjkl - select notes (vim movement)

Move selected note

• yuio - move note (vim movement, one row up)
• n/m - shorter/longer

Add/delete

• space - add note at view center
• x - delete selected note

View

• q/w - zoom out/in
• a/s - smushed/spread (vertical)

Grid sensitivity

• d/f - horizontal coarse/fine
• e/r - vertical coarse/fine

Pattern

• </> - previous/next pattern (editing)
• [/] - pattern length -/+
• c - clear pattern

Session

• h/l - cursor left/right (tracks)
• j/k - cursor up/down (patterns)
• space/enter - launch clip

Settings

• h/l - move between columns
• j/k - move between tracks
• enter - edit selected cell
• r - rescan MIDI devices

Running

go run .

Launchpad X: put in Programmer Mode (hold Session + bottom-right Scene button on startup).

Pattern Chaining (future)

• Chains: sequence of patterns that play in order
• Session device sees chains, not individual patterns
• Chain of length 1 = current behavior
• Allows song arrangement without duplicating pattern data