fix(prisma): Explain schema.prisma config settings

[Tobbe]

Had this comment first, but it felt like it was too long

// For CJS Cedar apps:
// It might feel a little out of place to have .mts files in the codebase, and
// especially importing them like we do in `src/lib/db`.
// For ESM Cedar apps:
// It might feel a little weird to ask Prisma to generate CJS compatible format.
//
// Setting `moduleFormat = "cjs"` and using `.mts` extensions is however the
// only combination that makes Prisma 7, which is ESM-only, work in CJS Cedar
// apps while also having the same configuration work for ESM Cedar apps.
//
// The only reason this works is thanks to Node 24's support for require(esm).
// https://www.prisma.io/docs/orm/prisma-schema/overview/generators

So I shortened it to what we have now, and then pointing here for more info.

This all came out of the discussion on PR #1752

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☁️ Nx Cloud last updated this comment at 2026-05-12 20:47:13 UTC

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☁️ Nx Cloud last updated this comment at 2026-05-12 17:09:42 UTC

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☁️ Nx Cloud last updated this comment at 2026-05-12 17:09:42 UTC

[greptile-apps]

Greptile Summary

Adds a 3-line explanatory comment above the generator client block in all 9 schema.prisma files, explaining that the moduleFormat = "cjs" / .mts extension combination is required to make Prisma 7 work across both CJS and ESM Cedar apps, with a link to PR #1761 for deeper context. The project overview doc (docs/implementation-docs/2026-03-26-cedarjs-project-overview.md) remains factually consistent — it already lists Prisma 7 and Node.js 24 in the runtime section, which aligns with the Node 24 require(esm) dependency described in the PR.

• All 9 schema.prisma files (four create-cedar-app templates, three test fixtures, two local-testing projects) receive the identical comment block.
• No schema, generator settings, or runtime behavior is changed — this is a documentation-only update.

Confidence Score: 5/5

Documentation-only change with no impact on runtime behavior; safe to merge.

Every changed file receives the same identical 3-line comment block. No generator settings, migrations, or code paths are modified. The comment text is accurate and consistent with the Prisma 7 / Node 24 setup already reflected in the codebase and project overview doc.

No files require special attention.

Important Files Changed

Filename	Overview
packages/create-cedar-app/templates/ts/api/db/schema.prisma	Adds a 3-line explanatory comment before the generator block linking to PR #1761 for context on the CJS/ESM settings combination
packages/create-cedar-app/templates/js/api/db/schema.prisma	Same explanatory comment addition as other templates
packages/create-cedar-app/templates/esm-ts/api/db/schema.prisma	Same explanatory comment addition as other templates
packages/create-cedar-app/templates/esm-js/api/db/schema.prisma	Same explanatory comment addition as other templates
fixtures/test-project/api/db/schema.prisma	Same explanatory comment addition as other fixtures
fixtures/test-project-esm/api/db/schema.prisma	Same explanatory comment addition as other fixtures
fixtures/test-project-live/api/db/schema.prisma	Same explanatory comment addition as other fixtures
local-testing-project/api/db/schema.prisma	Same explanatory comment addition as other local testing projects
local-testing-project-live/api/db/schema.prisma	Same explanatory comment addition as other local testing projects

_{Reviews (1): Last reviewed commit: "Update comment" | Re-trigger Greptile}

[github-actions]

The changes in this PR are now available on npm.

Try them out by running yarn cedar upgrade -t 5.0.0-canary.2326

Or try it in a new app with yarn dlx create-cedar-app@5.0.0-canary.2326