Overview

Comparing two versions of a board takes three steps:

1. Point kigit at a project: run it inside a KiCad project folder, give the folder with -C, or open it in the GUI.
2. Pick two revisions: commits, branches, tags, HEAD~3, or LOCAL for your uncommitted changes.
3. Read the page: kigit writes one HTML page and opens it in your browser, with the PCB and the schematic as tabs.

flowchart LR
    A[git history] -->|old revision| K(kigit)
    A -->|new revision| K
    K --> P[PCB diff]
    K --> S[Schematic diff]
    P --> H[viewer.html]
    S --> H

Minimal setup

cd ~/boards/my-board
kigit                      # HEAD vs the working tree (your uncommitted changes)
kigit HEAD~3               # HEAD~3 vs the working tree
kigit c46da63..HEAD        # two commits

The page is written to .kigit/ next to the board (or wherever -o FILE says) and opened in your browser. The terminal also prints a summary of the most-changed nets and of the schematic changes.

Which way to use it

You want to...	Use
Browse the history and click two commits	GUI
Compare from a script, a hook or CI	Command Line
Compare two copies of a project without git	Without Git

Colours

The same colours are used everywhere:

Colour	Meaning
Green	Added in the newer revision
Red (dashed on the schematic)	Removed
Blue	Moved (same item, new place)
Amber	Schematic part whose value, footprint or connections changed
Grey	Unchanged