Why .dt

Typed, versioned data contracts that compile to every warehouse.

Type safety primer
main.dt•
Hints On
TypeScript for data

Ship typed data contracts in .dt.

For CEOs/CTOs: Reduce data risk while keeping velocity with versioned contracts, not fragile SQL.

For engineers: Type safety and compile-time checks catch joins, aggregates, and schema drift early.

deet checkPortable SQLGit-native .dt files
Sources
2
users, orders
Transforms
4
1 joins • 1 aggregations • 1 sorts
Contracts
0
Define a model
Type safety now
module analytics
deet check
Clean
Contracts
0 models
Compile
Not run
Outputs
Pending
0 hintsAuto compile onTarget: DuckDB

Source Code

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Output

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deet check
Clean

Typecheck runs on every edit so you can fix issues before SQL compiles.

Type error demo

Inject a deliberate mismatch so deet check fails, then restore with one click.

CLI quick check
deet check
Type safety primer →
No type issues detected. Your contract is clean.

Contract view

Define a model to see its contract surface here.