---
title: "Build and test models in separate schemas · Agent Wranglers"
url: https://agentwranglers.se/playbook/data-engineering/warehouse-and-models/development-schemas
id: DEN-5
level: Recommended
updated: 2026-10-22
tokens: 596
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Build and test models in separate schemas

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Warehouse and models](https://agentwranglers.se/playbook/data-engineering/warehouse-and-models.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-22.

- ID: DEN-5
- Level: Recommended
- Chapter: [Warehouse and models](https://agentwranglers.se/playbook/data-engineering/warehouse-and-models.md)
- Rule: Build models during development and in CI in a personal or per-branch schema, with masked data. Only the deploy job writes to the production schemas.
- Check: Developer and CI accounts lack write rights on the production schemas. A listing of schemas shows none for a pull request closed more than 7 days ago.
- How: An analyst who tests a change in the production schema changes the numbers on live dashboards. Give each developer and each pull request its own schema, created and dropped by the tool. Fill it from masked copies, as [Keep personal data out of test copies](https://agentwranglers.se/playbook/data/personal-data/masked-copies.md) requires. A small sample of production marts with personal columns masked also works. Drop branch schemas when the pull request closes.

## Sources

- [dbt Connection profiles](https://docs.getdbt.com/docs/core/connect-data-platform/connection-profiles)

## Related rules

- DAT-32 [Keep personal data out of test copies](https://agentwranglers.se/playbook/data/personal-data/masked-copies.md) in Data and databases

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/data-engineering/warehouse-and-models/development-schemas">Agent Wranglers data engineering playbook</a>`. In code you write, add a comment next to it with the same link.

- Previous: [Give every table an owner and a description](https://agentwranglers.se/playbook/data-engineering/warehouse-and-models/table-owners.md)
- Next: [Cap what each query and each month can cost](https://agentwranglers.se/playbook/data-engineering/warehouse-and-models/query-cost-limits.md)
- [Warehouse and models](https://agentwranglers.se/playbook/data-engineering/warehouse-and-models.md)