git:20260809.e8d3666 to git:20260810.cf963da

32 added, 0 removed. Audit A to A.

---

name: cloudflare-production-builder

description: Design, review, debug, migrate, or deploy production systems on Cloudflare Workers and related Developer Platform products. Use for material architecture, durability, release, migration, rollback, or live-verification decisions across Workers, Durable Objects, D1, R2, Queues, Workflows, bindings, and routes.

---

# Cloudflare Production Builder

Apply this guidance proportionally. It is a production reasoning aid, not a

mandatory ceremony layer. Stay within the user's requested operation and do not

turn a diagnosis or recovery into an architecture program.

## Choose the operating mode

- **Answer or diagnose:** inspect only the evidence needed to explain the

behavior. Do not mutate or design a replacement unless asked.

- **Recover:** restore a known-good capability with the smallest supported,

reversible operation. Preserve evidence and defer refactoring.

- **Change or migrate:** design compatibility, durability, rollout, verification,

and rollback for the surfaces actually affected.

Do not mix recovery and refactoring in one production operation.

## Core contract

1. Identify authoritative state, the coordination key, the durability boundary,

and user-visible completion.

2. Treat source, build, upload, configuration, migration, traffic, route,

stateful lifecycle, and live behavior as separate facts only when the task

depends on those surfaces.

3. Prefer immutable artifacts and conditional pointer changes. Make external

mutations idempotent, fenced, conditional, or compensatable.

4. Classify errors before retrying. Persist terminal domain failures; bound

transient retries; reconcile ambiguous mutations before replay.

5. Preserve accepted work across handoff failures. Use a durable record and a

repair path when an initiating request can disappear.

6. Verify the owning live path and exact identity after a production mutation.

Use precise language such as `version uploaded`, `traffic switched`, and

`live smoke passed`.

## Proportional workflow

1. Inspect current code and provisioned state for the touched surface. Resolve

the exact account, environment, resource, bindings, and live version before

mutation.

2. State the intended authority and repair/rollback path. For simple work, one

sentence is enough.

3. Run focused local or remote checks that can falsify the change. Do not add

unrelated global gates.

4. When authorized to deploy, upload and inspect before switching when the

provider supports it. Use a verification path supported by the topology.

5. After mutation, verify only the affected rollout axes plus the user-visible

capability. Record exact identities and rollback evidence.

Pause when the exact production target, current state, retry safety, or rollback

target cannot be resolved. A blocker in an unrelated surface is not permission

to broaden the operation.

+ ## Integrate preview and newly launched capabilities safely

+ When a preview or newly launched Cloudflare capability materially improves the

+ design, use it deliberately rather than trusting remembered APIs:

+ 1. Retrieve current first-party docs and changelog entries at action time. Note

+ the capability's maturity, launch date, documented limits, and production

+ support status.

+ 2. Inspect the installed package's `package.json`, README/examples, exports, and

+ `.d.ts` files. Installed types are the compilation contract; marketing docs

+ are not.

+ 3. Put the preview surface behind a narrow adapter so churn does not spread

+ through domain code. Keep a supported fallback or an explicit failure mode

+ when the capability is not production-suitable.

+ 4. Pin the exact package version during the proving release. Compile and build

+ immediately after wiring each preview primitive; do not defer integration

+ feedback until the full system exists.

+ 5. Inspect generated artifacts, not just source: Worker entrypoint, generated

+ Wrangler config, asset directories, binding names, Durable Object migrations,

+ and the path the release system will actually upload.

+ 6. Scan the final bundle for `.dev.vars*`, `.env*`, credentials, and unexpected

+ local files. Fail or scrub the build before packaging; a clean Git ignore is

+ not evidence that build output is clean.

+ 7. Record the exact version and local evidence separately from live evidence.

+ Do not claim production behavior until the exact uploaded artifact, bindings,

+ routes, migrations, and owning live path have passed smoke verification.

+ Treat type casts between preview packages as an adapter concern and test the

+ runtime seam. Structurally similar workspace, loader, or RPC types from different

+ package versions can compile only after a cast while still disagreeing at

+ runtime.

## Load references selectively

- [primitive-selection.md](references/primitive-selection.md): use when the

product or coordination primitive is genuinely undecided.

- [durable-execution.md](references/durable-execution.md): use for asynchronous

handoffs, retries, queues, Workflows, or long-running external work.

- [storage-and-caching.md](references/storage-and-caching.md): use for storage,

cache, and authorization boundaries.

- [deployments-and-migrations.md](references/deployments-and-migrations.md): use

for multi-surface rollout, schema or Durable Object lifecycle, and rollback.

- [multitenant-hosting-and-security.md](references/multitenant-hosting-and-security.md):

use for untrusted code or tenant isolation.

- [observability-testing-and-cost.md](references/observability-testing-and-cost.md):

use when adding or reviewing telemetry, test layers, or spend controls.

Retrieve current first-party Cloudflare documentation before relying on API

signatures, configuration, limits, pricing, retention, or product support.