In the wild
We pointed mcdview at the schemas of well-known open-source projects, and rebuilt each one's history from its own git log. Ten live diagrams, each with a time-lapse of how the database grew and a diff you can read at a glance.
The trick is that many projects keep their whole schema in a single committed
file: a Rails db/schema.rb, a PostgreSQL db/structure.sql,
or a Prisma schema.prisma. That file's git history is the
schema's history. We walked the commits, kept one state per structural change,
and replayed them into mcdview with their real dates, pinned as versions. mcdview
reads all three formats directly, no conversion.
One honest caveat: a diagram only shows the foreign keys a project actually declares in its database. Some apps keep relations in application code, so their early diagrams look sparse even when the tables are related.
Each has three links: the current diagram, a time-lapse of its whole history, and one diff worth a look. Open the diagram, click a table to isolate it, follow a foreign key, switch to dark mode.
The decentralized social network at the heart of the fediverse (ActivityPub).
Diagram · Time-lapse · A diff · GitHub
The DevOps platform: Git hosting, CI/CD, issues. (This public mirror's schema stops in 2020.)
Diagram · Time-lapse · A diff · GitHub
The modern open-source discussion platform. Its Postgres structure.sql, 363 tables today.
Diagram · Time-lapse · A diff · GitHub
Open-source scheduling, the Calendly alternative. A Prisma schema.
Diagram · Time-lapse · A diff · GitHub
The computing-focused link-aggregation community (a cousin of this very demo).
Diagram · Time-lapse · A diff · GitHub
A pioneer of the decentralized social web. Schema history runs 2010 to 2016.
Diagram · Time-lapse · A diff · GitHub
Open-source document signing, the DocuSign alternative.
Diagram · Time-lapse · A diff · GitHub
Privacy-friendly web analytics, a small and legible schema.
Diagram · Time-lapse · A diff · GitHub
Want your project here, kept current automatically? Paste a schema on mcdview.dev, or wire it into CI so the diagram updates on every push. See Keep a diagram updated on every push.