AWS Lambda
AWS Lambda
AWS Lambda API creates, updates, and invokes serverless functions — the core of the AWS serverless ecosystem.
Pay per invocation and execution time — no idle cost
Cold starts remain a hidden tax for high-QPS endpoints
All AWS APIs use SigV4 signing (handled automatically by the AWS SDK in almost every case). Create an access key in the AWS Console or IAM, run aws configure locally, then import the AWS SDK and call CreateFunction, Invoke, etc. For production prefer IAM Roles + Identity Providers over long-lived access keys.
Uptime · 30-day window
GitHub activity
About this API
AWS Lambda is AWS's serverless compute service — you upload function code (zip or container image), define triggers (HTTP, S3, DynamoDB events, schedulers, etc.), and Lambda spins up a container to run your code on each event, billing per invocation and millisecond of execution time with no idle cost.
The Lambda API is the REST interface behind the AWS Console, wrapped by AWS SDKs in every major language. Through it you can create/update/delete functions, configure environment variables and IAM roles, attach trigger sources, Invoke synchronously or asynchronously, and query logs through CloudWatch Logs. Function code can be a zip (50MB max) or a container image (10GB max); the latter unlocks heavy dependencies, particularly important for ML inference workloads.
Real-world projects typically use IaC tools like Serverless Framework, SAM, or CDK — all of which call the Lambda API under the hood. Cold starts (first invocation or after idle periods) are a serverless reality; AWS keeps improving them with SnapStart (Java) and Provisioned Concurrency. Single executions are hard-capped at 15 minutes; longer jobs need decomposition or Fargate/Step Functions.
What you can build
- 1Build serverless backends behind API Gateway
- 2Process events from S3, DynamoDB, SQS, etc.
- 3Run scheduled jobs via CloudWatch Events
- 4Distribute function versions across accounts and regions
- 5Embed functions into Step Functions state machines
Strengths & limitations
Strengths
- Pay per invocation and execution time — no idle cost
- Native triggers from 200+ AWS services
- Cold starts keep improving; container images support heavy dependencies
- Provisioned Concurrency eliminates cold starts on critical paths
Limitations
- Cold starts remain a hidden tax for high-QPS endpoints
- Single invocation capped at 15 minutes — long jobs need decomposition or Fargate
- Function package size limit is 50MB zipped or 10GB as a container image
Example request
curl https://github.com/mermade/aws2openapi/<endpoint> \
-H "Authorization: Bearer $API_KEY"
# Some providers use X-Api-Key instead — verify in the docs.Getting started
All AWS APIs use SigV4 signing (handled automatically by the AWS SDK in almost every case). Create an access key in the AWS Console or IAM, run aws configure locally, then import the AWS SDK and call CreateFunction, Invoke, etc. For production prefer IAM Roles + Identity Providers over long-lived access keys.
FAQ
How big is the Lambda free tier?+
1M free invocations and 400,000 GB·s of compute per month — small projects almost never exhaust it.
How bad are cold starts?+
Depends on runtime and package size. Node/Python typically tens to hundreds of ms; Java/.NET can hit seconds — use Provisioned Concurrency or SnapStart to remove them on critical paths.
Can Lambda use GPUs?+
No — for GPU workloads use SageMaker, AWS Batch, EC2, or ECS/EKS.
Where do function logs go?+
CloudWatch Logs — each function has its own log group automatically. You can subscribe log groups to forward to external analytics systems.
Technical details
- Auth type
- api_key
- Pricing
- freemium
- Protocols
- REST
- SDKs
- python, javascript, typescript, java, go, ruby, csharp
- Response time
- 21 ms
- Last health check
- 5/12/2026, 7:36:33 AM
Endpoints
Parsed from the OpenAPI spec. Showing 12 of 65 non-deprecated endpoints.
/2015-03-31/event-source-mappings//2015-03-31/event-source-mappings//2015-03-31/event-source-mappings/{UUID}/2015-03-31/event-source-mappings/{UUID}/2015-03-31/event-source-mappings/{UUID}/2015-03-31/functions/2015-03-31/functions//2015-03-31/functions/{FunctionName}/2015-03-31/functions/{FunctionName}/2015-03-31/functions/{FunctionName}/aliases/2015-03-31/functions/{FunctionName}/aliases/2015-03-31/functions/{FunctionName}/aliases/{Name}53 more endpoints not shown. See the OpenAPI spec for the full list.
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