Schemity is an ERD tool with JSON storage: each connection - its schema, layout, views, and annotations - is saved as one plain JSON file on your disk. There is no proprietary binary format and no cloud database holding your work hostage.
Why JSON
A binary or cloud format locks your schema inside someone else’s tool. JSON does the opposite:
- Readable - open the file in any editor and recognize your entities.
- Diff-friendly - changes show up as clean line-by-line diffs in Git.
- Portable - the file is yours, with no export step required.
- Scriptable - other tooling can read it if you ever need it to.
What is in the file
One connection’s JSON captures everything the diagram contains:
- ents - entities and their fields, with types, keys, defaults, and constraints
- rels - relationships and their cardinality and referential actions
- legends - annotation boxes
- contextViews - every context view, with its included entities, layout, and routing
- templates - reusable field templates
- logs - a change history of the diagram
- conn - the connection metadata (engine, naming convention, host, and so on)
Where the files live
A local workspace lives at ~/schemity/<workspace-id>/, with a small meta.json and one <connection-id>.json per connection. If you import a workspace into a Git repository, those same files live in the folder you chose.
Passwords are not in the file
Database and SSH passwords are never written to the JSON. Schemity stores them in your operating system’s keychain, so you can safely commit and share the diagram files.
Own your data
Because the source of truth is a file you control, Schemity stays a local ERD tool with no cloud. Back it up, move it between machines, or keep it on an air-gapped laptop - the diagram goes wherever the file goes.
Next
Put the file to work in Version Control in Git.