new-module

name: new-module description: Create a new VCV Rack module (Faust DSP or native C++) using architect → builder → verify/fix cycle argument-hint: [description]

Create New Module: $ARGUMENTS

Workflow

This skill creates a new VCV Rack module through a multi-phase agent cycle.

Phase 0: Determine Implementation Type

IMPORTANT: Before starting implementation, determine whether this module should be:

Ask the user if unclear. Simple CV utilities (mixing, crossfading, logic) should almost always be native C++. Complex audio processing benefits from Faust's DSP primitives and automatic parameter handling.

For native C++ modules:

• Skip the Faust-specific steps (no .dsp file, no test infrastructure updates)
• No test_config.json needed (test framework is Faust-specific)
• Simpler CMakeLists.txt (no add_faust_dsp())

Phase 1: Create Feature Branch

git checkout -b feature/{module-name-lowercase}

This ensures all module development happens on an isolated branch.

Phase 2: Save Specification

First, save the module specification to specs/{ModuleName}.md:

# {ModuleName} Module Specification

## Overview
{Brief description of what the module does}

## Type
[instrument / filter / effect / resonator / utility]

## Sonic Character
{Describe the sound - warm, harsh, ethereal, punchy, etc.}

## Parameters
- **param1**: Description (range: 0-1, default: 0.5)
- **param2**: Description

## Inputs
- **gate**: Gate signal for triggering
- **volts**: V/Oct pitch CV
- [other inputs]

## Outputs
- **out_l/out_r**: Stereo audio output

## Inspiration / References
{Any DSP algorithms, synths, or effects to reference}

## Special Requirements
{Any specific technical requirements}

Phase 3: Design (Architect) - Faust modules only

For Faust modules, spawn the architect agent:

Task tool:
  subagent_type: "module-dev:architect"
  description: "Design {ModuleName}"
  prompt: "Read the specification at specs/{ModuleName}.md and create a detailed technical design for implementation."

For native C++ modules, skip this phase and implement directly.

Phase 4: Build (Builder)

For Faust modules, spawn the builder agent:

Task tool:
  subagent_type: "module-dev:builder"
  description: "Build {ModuleName}"
  prompt: "Create all files for {ModuleName} based on this design:\n\n{ARCHITECT_OUTPUT}"

For native C++ modules, create the files directly (see File Checklist below).

Phase 5: Verify/Fix Loop (Faust modules only)

Run the standard module-dev verification loop:

Task tool:
  subagent_type: "module-dev:verifier"
  description: "Verify {ModuleName}"
  prompt: "Verify the {ModuleName} module. Return metrics and verdict."

If NEEDS_WORK:

Task tool:
  subagent_type: "module-dev:judge"
  description: "Judge {ModuleName}"
  prompt: "Evaluate these verification results:\n\n{VERIFIER_OUTPUT}"

Then fix and repeat until PASS.

Quick Reference - Just Commands

File Checklist

All Modules (Faust and Native C++)

New Files:

• src/modules/{ModuleName}/{ModuleName}.cpp - Module implementation
• src/modules/{ModuleName}/CMakeLists.txt - Build config
• res/{ModuleName}.png - Faceplate (generate with just faceplate)

Updated Files:

• src/plugin.cpp - extern + addModel (with HAS_* guard)
• CMakeLists.txt - HAS_* compile definition
• plugin.json - module entry
• README.md - add to module table and update count
• scripts/generate_faceplate.py - HP width

Faust Modules Only (additional files)

New Files:

• src/modules/{ModuleName}/{lowercase}.dsp - Faust DSP code
• src/modules/{ModuleName}/test_config.json - Test configuration

Updated Files:

• test/faust_render.cpp - factory declaration
• test/dsp_wrappers.cpp - DSP wrapper
• test/CMakeLists.txt - module mapping

Example Usage

/new-module ChaosSynth A chaotic subtractive synthesizer with Lorenz attractor modulation

This will:

1. Create branch feature/chaossynth
2. Save spec to specs/ChaosSynth.md
3. Architect designs the module
4. Builder creates all files
5. Verifier/Judge/Dev loop until passing

After module passes verification, you can create a PR:

git add .
git commit -m "feat: Add ChaosSynth module"
git push -u origin feature/chaossynth
gh pr create --title "Add ChaosSynth module" --body "..."

Module Types Reference