Introduction

cadvm (CAD Version Manager) is a local-first version control system for CAD files — STEP/STP (B-Rep) and STL/OBJ (triangle mesh). It brings Git-like workflows — snapshots, branches, diff, checkout, revert — to CAD data, and goes further with a geometric diff and a 3D viewer that show what actually changed in the geometry, not just in the bytes.

cadvm init
cadvm snapshot -m "Cube with a Ø5 hole"
# …edit the part…
cadvm snapshot -m "Ø5 → Ø8"
cadvm geom-diff HEAD~1 HEAD     # volumes added / removed / common
cadvm view HEAD~1 HEAD          # interactive 3D diff in your browser
cadvm ui                        # full-screen terminal dashboard

Why cadvm?

CAD files are awful to version with Git: a tiny geometric edit re-exports the whole STEP file with renumbered entities and a new timestamp, so a textual diff is pure noise. cadvm instead:

• stores versions deduplicated (content-addressed, gzip-compressed chunks);
• summarizes each file with light metadata (STEP schema/entities, or mesh triangle/vertex counts);
• computes a real geometric diff (added / removed / common) — via Open CASCADE for STEP/STP, and a pure-Rust triangle diff for STL/OBJ;
• renders that diff in a self-contained 3D HTML viewer (no server, no cloud).

🧊 See it live: the Live demo embeds a real diff you can rotate and zoom right in your browser.

Architecture

cadvm is built in three layers:

The Rust core never links Open CASCADE directly — it calls the cadvm-geom helper as a subprocess, keeping the heavy CAD dependency isolated. Open CASCADE is needed only for the STEP/STP geometric diff; the VCS, the TUI and the STL/OBJ mesh diff all work without it.

Crates

• cadvm-store — content-addressed storage (BLAKE3, blobs, chunks).
• cadvm-core — repository logic.
• cadvm-cli — the cadvm binary (CLI + TUI).
• cpp/cadvm-geom — the C++/OCCT geometry helper.

The API reference (rustdoc) documents these crates.

Continue with Installation.