AWS Lambda

Run your Telo manifest as an AWS Lambda function. One manifest equals one Lambda artifact — the manifest declares which AWS event sources the Lambda accepts and what each handler does; Telo owns the AWS-facing transport.

Why use this

• One artifact, multiple sources — a single Lambda.Function lists HTTP API, SQS, and direct handlers; Telo routes each event to the matching one.
• Source-shaped handler kinds — Lambda.HttpApi, Lambda.Sqs, and Lambda.Direct each carry the right matcher, inputs, and returns/catches contract for their source.
• Two runtime models, one manifest — managed Node.js (nodejs24.x) or custom (provided.al2023 / containers); pick a model by which bootstrap file you copy.
• Partial-batch SQS — Lambda.Sqs emits the standard batchItemFailures envelope so retries scope to failed messages.
• Cold-start friendly — x-telo-scope lets you defer expensive resource init until the first request that needs it.

Kinds

Kind	Purpose
Lambda.Function	Represents the AWS Lambda function (one ARN). Required in every manifest.
Lambda.HttpApi	API Gateway HTTP API v2 trigger — routes, matchers, returns/catches rendering, CORS.
Lambda.Sqs	SQS queue trigger with partial-batch-failure support.
Lambda.Direct	Catch-all for synchronous invokes (SDK, Step Functions, EventBridge Scheduler, internal RPC).
Lambda.Handler	Abstract dispatch contract every concrete handler kind extends.

Example

kind: Telo.Application
metadata: { name: my-lambda, version: 1.0.0 }
imports:
  Lambda: aws/lambda@1.0.1
  JS: std/javascript@0.5.0
targets: [ !ref Main ]
---
kind: JS.Script
metadata: { name: Worker }
code: |
  function main(input) {
    return { ok: true, received: input.payload };
  }
---
kind: Lambda.Direct
metadata: { name: AdminTools }
handler: { kind: JS.Script, name: Worker }
inputs:
  payload: "${{ event }}"
---
kind: Lambda.Function
metadata: { name: Main }
handlers:
  - { kind: Lambda.Direct, name: AdminTools }

Reference

• Lambda.HttpApi — routes, request matching, response rendering, CORS.
• Lambda.Sqs — batch handling, partial-batch failures.
• Lambda.Direct — synchronous invokes, returns matching.
• Deploying to AWS Lambda — packaging, both runtime models, SAM / CDK / Terraform snippets.
• Cold Starts — keeping init time under AWS's budget, x-telo-scope patterns.

Picking a Handler Kind

Source	Use
HTTP request via API Gateway HTTP API v2	Lambda.HttpApi
SQS message batch	Lambda.Sqs
Synchronous SDK invoke, Step Functions, EventBridge Scheduler, internal RPC	Lambda.Direct

A single Lambda.Function can list multiple handler kinds. Bind the AWS-side event source mappings (API Gateway, SQS, etc.) to the same Lambda ARN and Telo routes each event to the matching handler:

kind: Lambda.Function
metadata: { name: Main }
handlers:
  - { kind: Lambda.HttpApi, name: WebApi }
  - { kind: Lambda.Sqs, name: OrderProcessor }
  - { kind: Lambda.Direct, name: AdminTools }

Deployment

Telo supports both AWS Lambda runtime models. The manifest is identical across them — you pick a model by which bootstrap file you copy into the artifact.

Runtime	Bootstrap	When to use
Managed Node (nodejs24.x)	cp node_modules/@telorun/lambda/managed.mjs ./index.mjs	Most cases. AWS owns the outer loop and calls your exported handler.
Custom (provided.al2023 / container image)	cp node_modules/@telorun/lambda/custom.mjs ./bootstrap	Containers, SnapStart-incompatible runtimes, anywhere you want full control over the boot sequence.

The same manifest runs under either model — Telo detects which one AWS is using and adapts. You only change which bootstrap you copy.

Examples

Working manifests under examples/aws/lambda/:

• direct.yaml — minimal Lambda.Direct setup.
• http-api.yaml — two HTTP routes with CORS and structured error rendering.
• sqs.yaml — SQS batch handling with per-message retry reporting.
• multi-kind.yaml — one Lambda artifact serving all three event sources.