Use familiar AWS tooling
Keep the CLI, CDK, SDKs, and Terraform workflows where Overcast already supports the services you need. Start by changing the endpoint URL, then check the support matrix for gaps.
alpha local cloud emulation for developers
Develop against AWS-compatible services on your laptop and in CI.
Overcast is a free, MIT-licensed local emulator for AWS APIs. Run it with Docker, point supported AWS CLI,
CDK, or SDK workflows at localhost:4566, and inspect what your app creates in the included web
UI.
>_ start overcast
docker run --rm \
-p 4566:4566 \
-p 4567:4567 \
ghcr.io/overcast-sh/overcast:latest50
services registered
1308
implemented operations
4566
default API port
No paid feature gates
Use implemented features without an auth token, telemetry, usage limits, or a paid tier. The support matrix
shows what works today and what intentionally returns 501.
Inspect local state
Use the web UI to inspect resources, follow the event stream, view metrics, and debug SNS, SQS, Lambda, and email flows while your tests run.
service implementation
Check listed operations before you depend on them
API Gateway 104/106
listed operations implemented
CloudFront 89/89
listed operations implemented
AppSync 82/82
listed operations implemented
IAM 74/74
listed operations implemented
EC2 / VPC 72/72
listed operations implemented
Cognito 70/70
listed operations implemented
Lambda 57/59
listed operations implemented
EKS 50/50
listed operations implemented
docs from release source
Documentation follows the tracked Overcast release.
This site includes 61 public documentation pages from the configured Overcast source ref
v0.0.1-alpha.38. Published docs stay tied to the
release they describe, while internal plans and contributor-only notes stay out of the public site.