cloudformation (parlel)
A zero-dependency, in-process fake of AWS CloudFormation. Speaks the AWS Query
(XML) wire protocol, API version 2010-05-15.
| Field | Value |
|---|---|
| Service | cloudformation |
| Port | 4564 |
| Protocol | AWS Query / XML |
| Health | GET /_parlel/health |
| Reset | POST /_parlel/reset |
Default connection
AWS_ENDPOINT_URL=http://127.0.0.1:4564
AWS_REGION=us-east-1
AWS_ACCESS_KEY_ID=parlel
AWS_SECRET_ACCESS_KEY=parlel
Any credentials are accepted.
Supported operations
| Operation | Notes |
|---|---|
| CreateStack | Parses a JSON template's Resources/Outputs/Parameters. |
| DescribeStacks | Returns status, parameters, outputs, tags. |
| UpdateStack | Re-applies template/parameters; status UPDATE_COMPLETE. |
| DeleteStack | Idempotent; status DELETE_COMPLETE. |
| ListStacks | Optional StackStatusFilter. |
| GetTemplate | Returns the original template body. |
| CreateChangeSet | CREATE or UPDATE; computes resource changes. |
| DescribeChangeSet | Returns change list + parameters. |
| ExecuteChangeSet | Applies the change set to the stack. |
| ListChangeSets | Per-stack change set summaries. |
| DescribeStackResources | Per-resource detail. |
| ListStackResources | Resource summaries. |
| ListExports | Outputs with an Export.Name. |
| ValidateTemplate | Returns template parameters + description. |
SDK example
import { CloudFormationClient, CreateStackCommand } from "@aws-sdk/client-cloudformation";
const cfn = new CloudFormationClient({
endpoint: "http://127.0.0.1:4564",
region: "us-east-1",
credentials: { accessKeyId: "parlel", secretAccessKey: "parlel" },
});
await cfn.send(new CreateStackCommand({
StackName: "demo",
TemplateBody: JSON.stringify({ Resources: { B: { Type: "AWS::S3::Bucket" } } }),
}));
Access via MCP / preview URL
When running under the parlel pool, this service is reachable through the MCP gateway and the preview URL assigned to the pool. Use the same operations over the preview URL host; credentials are still ignored.
Surface coverage
This emulator faithfully replicates the API surface most application code and agents exercise. Anything below the supported lines is either an intentional design choice for a fast, zero-cost local emulator (✓ By design) or a candidate for a future release (⟳ Roadmap) — never a silent inaccuracy.
Legend: ✅ fully supported · ◐ accepted (stored, not strictly enforced) · ✓ by design · ⟳ on the roadmap.
| Area | Limitation |
|---|---|
| Templates | JSON only (no full YAML parser). |
| Intrinsics | Only simple { "Ref": "Param" } resolved in outputs. |
| Provisioning | Resources are simulated, not actually created. |
| Drift / rollback | Not modeled (status always NOT_CHECKED). |
| Async states | All operations complete synchronously. |
Configuration — test.env
Copy these into your test.env (used by the bridge sidecar flow). Tokens are Parlel's seeded test credentials — any non-empty value is accepted by the emulator, so you rarely need to change them. Swap in real credentials only when pointing at the live service in prod.env.
AWS_ACCESS_KEY_ID=parlel
AWS_SECRET_ACCESS_KEY=parlel
AWS_REGION=us-east-1
AWS_ENDPOINT_URL_CLOUDFORMATION=http://parlel-bridge:4564
AWS_ENDPOINT_URL=http://parlel-bridge:4564