Comparison

Lucid Train compared with GitDiagram.

GitDiagram needs no install to look at a public repo. Lucid Train is for the one you work in every day.

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$curl -fsSL https://lucidtrain.com/install.sh | sh

GitDiagram is a free open-source web tool with a memorable trick: replace hub with diagram in a GitHub URL and it produces an interactive diagram of that repository. It needs no install, no account and no configuration, which makes it a four-second way to orient yourself in a public project you have never seen. Lucid Train solves a different problem: it is a desktop application reading a repository on your machine, including private and uncommitted work, that keeps the diagram, versions it, and can hand it to a coding agent.

Credit where it is due

The URL trick is excellent product design. There is no install, no account and no configuration, and for orienting yourself in an unfamiliar open-source project it is hard to beat something that takes four seconds. Nothing below is an argument that you should stop using it for that.

Where it stops being the right tool

It is oriented around GitHub URLs, so uncommitted work and code that is not on GitHub are outside its model. It is a viewer rather than an editor: the diagram is generated and shown rather than kept, refined, versioned and made part of your documentation. And a hosted tool means the analysis happens somewhere other than your machine.

What a persistent diagram buys

Lucid Train keeps diagrams as files with up to fifty versions each, lets you edit the graph and re-solve the layout, exports SVG that renders natively in a GitHub README, and writes a markdown architecture section into the repository. That is the difference between looking at a diagram and having one.

And then the code

The diagram becomes a specification for a coding turn in the same window, on the same repository, with reviewable diffs. That is the thing a viewer cannot do by construction, and it is the reason the two tools are not really substitutes.

Side by side

	Lucid Train	GitDiagram
Where it runs	Desktop app	Browser, hosted
Install needed	Yes	No
Reads uncommitted local work	Yes	No
Diagram is kept and versioned	Yes, 50 per diagram	No
Editable and re-solved	Yes	No
Runs fully offline	Yes	No
Diagram to code as a specification	Yes	No
Price	CLI free and open source; desktop $3/month, 7-day trial, no card	Free and open source

FAQ

Questions

Is GitDiagram free?

Yes, it is free and open source. For orienting yourself in an unfamiliar public repository it is an excellent tool and this page is not arguing otherwise.

Can it diagram private or local code?

It is built around GitHub URLs. Lucid Train reads the working tree on your machine, so private repositories and uncommitted changes are in scope.

Do I keep the diagram?

With GitDiagram you are looking at generated output. Lucid Train stores diagrams as files with version history and exports them into your repository.

Affiliation

Lucid Train is an independent product and is not affiliated with, endorsed by, or connected to the product described on this page. All names and trademarks belong to their respective owners. Pricing and features were checked on 22 August 2026 and change without notice; check the vendor's own site before deciding.

Lucid Train vs D2
D2 is a language you write. Lucid Train reads the code and writes the graph for you.
Lucid Train vs Multiplayer
Multiplayer starts from a production incident. Lucid Train starts from the shape of the code.
Lucid Train vs Cline
Both are provider-agnostic and both run local. One lives in your editor; one draws your architecture.
Lucid Train vs OpenCode
Not either-or. Lucid Train can run OpenCode as its engine.

Last updated 22 August 2026