# jitx

> Base skill for JITX hardware design workflow. Use when working with JITX Python projects for PCB design, circuit creation, or component modeling. Provides environment setup verification, build commands, project structure guidance, documentation lookup, and navigation to specialized subskills (component-modeler, etc.). Triggers on any JITX-related task or when user mentions JITX, circuits, PCB design, or hardware. Also triggers when user asks about JITX APIs, landpattern generators, protocols, or needs to look up JITX documentation. IMPORTANT - When user provides a datasheet or asks to create/model a component, ALWAYS invoke the jitx-component-modeler subskill.

- Author: Duncan
- Repository: JITx-Inc/jitx-skills
- Version: 20260204215630
- Stars: 0
- Forks: 0
- Last Updated: 2026-02-06
- Source: https://github.com/JITx-Inc/jitx-skills
- Web: https://mule.run/skillshub/@@JITx-Inc/jitx-skills~jitx:20260204215630

---

---
name: jitx
description: Base skill for JITX hardware design workflow. Use when working with JITX Python projects for PCB design, circuit creation, or component modeling. Provides environment setup verification, build commands, project structure guidance, documentation lookup, and navigation to specialized subskills (component-modeler, etc.). Triggers on any JITX-related task or when user mentions JITX, circuits, PCB design, or hardware. Also triggers when user asks about JITX APIs, landpattern generators, protocols, or needs to look up JITX documentation. IMPORTANT - When user provides a datasheet or asks to create/model a component, ALWAYS invoke the jitx-component-modeler subskill.
---

# JITX Workflow Skill

Base skill for JITX hardware design automation. JITX is a Python framework for programmatic PCB design.

## Environment Setup

Before any JITX work, check and fix the environment automatically:

```bash
# Check for JITX project
if [ ! -f pyproject.toml ] || ! grep -q "jitx" pyproject.toml; then
  echo "ERROR: Not a JITX project (no pyproject.toml with jitx dependency)"
  exit 1
fi

# Create venv if missing
if [ ! -d .venv ]; then
  echo "Creating virtual environment..."
  python3 -m venv .venv
fi

# Activate venv and install deps
source .venv/bin/activate
pip install -e . --quiet

# Verify
python -c "import jitx; print(f'JITX ready: {jitx.__version__}')"
```

Run this automatically when starting JITX work. Don't ask user to do manual setup.

## IDE Setup (Recommended)

Install the Pyright LSP plugin for Python type checking:

```bash
claude plugin install pyright-lsp@claude-plugins-official
```

The plugin provides:
- Real-time type errors before running builds
- Autocomplete for JITX APIs (jitx, jitxlib, jitxstd)
- Import resolution and hover documentation

**Requires:** `pyright` or `pyright-langserver` installed:
```bash
pip install pyright
# or
npm install -g pyright
```

**Verify:** Ask Claude to "check for type errors" or run manually:
```bash
pyright src/
```

## Running JITX Designs

```bash
# Build a specific design
python -m jitx build <module.path.DesignClass>

# Build all designs in project
python -m jitx build-all
```

**Success output:** `status: ok`
**Error output:** Python traceback or `status: error`

**Output files** (in `designs/<design_name>/`):
- `cache/netlist.json` - JSON netlist for verification
- `cache/design-explorer.json` - Design hierarchy
- `design-info/stable.design` - Design snapshot

## Project Structure

Standard JITX project layout:
```
project/
├── pyproject.toml          # Project config with JITX deps
├── src/<namespace>/
│   ├── components/         # Custom component definitions
│   │   ├── <category>/     # mcus, connectors, power, etc.
│   │   │   └── <mfr>_<mpn>.py
│   │   └── __init__.py
│   ├── circuits/           # Reusable circuit blocks
│   └── designs/            # Top-level designs
├── designs/                # Build output directory
└── .venv/                  # Virtual environment
```

## Core Concepts

**Circuit**: Python class inheriting from `jitx.Circuit`. Contains components and connections.

**Component**: Python class inheriting from `jitx.Component`. Defines ports, landpattern, symbol.

**Design**: Python class inheriting from design base (e.g., `SampleDesign`). Top-level entry point.

**Net operators**:
- `+` : Unordered connection (add to net set)
- `>>` : Topology operator for ordered routing
- `self +=` : Add connections to circuit

## Subskills

### Component Modeler (`jitx-component-modeler`)

**ALWAYS invoke this subskill** when user:
- Provides a datasheet PDF (file path or URL)
- Asks to "create a component", "model a part", or "add a component"
- Mentions specific part numbers (e.g., "NE555", "RP2040", "LM1117")

**How to invoke:** Use the Skill tool with `skill: "jitx-skills:jitx-component-modeler"`

Supports:
- BGA, QFN, SOIC, SON, SOT packages
- Multi-unit symbols and thermal pads
- Complex pin mappings
- Batch component creation

**Do NOT attempt component generation without invoking this subskill** - it contains critical patterns, dimension mappings, and code templates.

### Coming Soon
- Circuit templates
- Design patterns
- Signal integrity constraints

## Documentation Lookup

JITX docs: `https://docs.jitx.com/en/latest/`

**When to fetch docs:**
- Unfamiliar API class or method → fetch API reference page
- Protocol wiring (USB, Ethernet, I2C) → fetch protocol docs
- Landpattern generator parameters → fetch generator docs
- UI commands or shortcuts → fetch UI command page
- Design patterns (pin assignment, SI constraints) → fetch essentials page

**How to look up:**
1. Read `references/docs-index.md` to find the right page URL
2. Use WebFetch to retrieve the page content
3. Apply the information to the task

**Common lookups:**

| Topic | Doc Path |
|-------|----------|
| Pin assignment | `essentials/design/pin_assignment.html` |
| Design hierarchy | `essentials/design/design-hierarchy.html` |
| Autorouter | `essentials/physical_design/autorouter.html` |
| SI constraints | `essentials/SI/constraints.html` |
| Component class | `api/jitx.component.html` |
| Circuit class | `api/jitx.circuit.html` |
| QFN landpattern | `jitxlib-standard/jitxlib.landpatterns.generators.qfn.html` |
| BGA landpattern | `jitxlib-standard/jitxlib.landpatterns.generators.bga.html` |
| USB protocol | `jitxlib-standard/jitxlib.protocols.usb.html` |
| Box symbol | `jitxlib-standard/jitxlib.symbols.box.html` |

For complete index with all pages, see `references/docs-index.md`.

## Quick Reference

| Task | Command/Pattern |
|------|-----------------|
| Build design | `python -m jitx build module.Design` |