Splice

What it does

Splice is a specialized CAD tool for designing cable harnesses and electrical assemblies. It provides an interactive SVG canvas for placing connectors, routing wires, assigning signals, and generating documentation. The tool includes a Harness Builder for drag-and-drop design, a Component Creator for custom parts (connectors, motors, relays, power supplies), and a Cable Creator for defining multi-core cables with conductor properties. It automatically generates bills of materials (BOMs) and supports export to SVG, PNG, and PDF. Splice also offers version control, a parts database with fuzzy search, and an expanding library of connectors from manufacturers like JST, Molex, Samtec, and TE Connectivity.

Who it is for

Splice is designed for engineers and technicians who need to design and document cable harnesses and wiring assemblies. It is suitable for industries such as avionics, CNC manufacturing, industrial power distribution, and any field requiring precise electrical interconnect documentation. The tool is free and runs natively on macOS, Windows, and Linux, with offline capability and filesystem integration.

Why it matters

Traditional CAD tools are often overkill or ill-suited for cable harness design, leading to manual, error-prone processes. Splice fills a niche by providing a purpose-built, free tool that streamlines harness creation, reduces errors, and automates BOM generation. Its MCP server, web embed, and Python library enable integration with AI agents and automation workflows, making it a modern solution for electrical assembly design.

Launch signal

Splice was launched on Hacker News as a Show HN post titled "Show HN: Splice – CAD for Cable Harnesses and Electrical Assemblies." The website is live at splice-cad.com, and the tool is available for download. The project includes open-source components on GitHub (splice-cad-mcp, splice-embed, splice-py).

Brand and naming

The name "Splice" directly references the action of joining cables, making it intuitive for the target audience. The tagline "CAD for Cable Harnesses and Electrical Assemblies" clearly positions the product. The brand is functional and straightforward, emphasizing utility over flashiness.