lambda-api

library5.5.0jsnpmunverified

lambda-api is a zero-dependency, lightweight web framework designed specifically for building serverless applications on AWS Lambda. It supports both AWS API Gateway Lambda Proxy Integration and ALB Lambda Target Support, providing a minimal yet familiar API similar to Express.js or Fastify for routing, middleware, and error handling. Optimized for the stateless, single-run execution model of Lambda, it prioritizes fast cold starts and low memory consumption by eschewing external dependencies. The package is currently at version 1.2.0, with a consistent release cadence of minor versions to introduce new features, enhance TypeScript type definitions, and resolve bugs. Its primary differentiation lies in its minimal footprint and dedicated focus on the unique demands of serverless environments, making it ideal for high-performance, cost-efficient serverless APIs.

web-framework aws

npm install lambda-api

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · LAMBDA-API

lambda-api

web-frameworkjavascriptv5.5.0

Install

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Import

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Disk

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Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

api

✓ import lambdaApi from 'lambda-api'; const api = lambdaApi();

✗ import { api } from 'lambda-api'; // Incorrectly assumes named export const api = new API(); // Incorrectly assumes class constructor

The default export is a function that needs to be invoked to get the API instance. For CommonJS, use `const api = require('lambda-api')();`.

API

✓ import type { API } from 'lambda-api';

✗ import { API } from 'lambda-api'; // Incorrectly imports the type as a value import API from 'lambda-api'; // Incorrectly assumes default export is the type

This is a type-only import for the main API interface, useful for TypeScript projects. Other types like `Request` and `Response` are also available for import.

CommonJS (API instance)

✓ const api = require('lambda-api')();

✗ const lambdaApi = require('lambda-api'); const api = lambdaApi; // Fails to invoke the factory function const { api } = require('lambda-api'); // Incorrectly assumes named export

For CommonJS modules, the `require` call must be immediately invoked as it exports a factory function that returns the API instance.

This quickstart demonstrates how to initialize `lambda-api`, define a simple GET and POST route, and expose it as an AWS Lambda handler.

import lambdaApi from 'lambda-api'; const api = lambdaApi(); // Define a route that responds with a status object api.get('/status', async (req, res) => { return { status: 'ok', timestamp: new Date().toISOString() }; }); // Define a route that handles a POST request with a body api.post('/greet', async (req, res) => { const name = req.body?.name || 'Guest'; return { message: `Hello, ${name}!` }; }); // Declare your Lambda handler function export const handler = async (event, context) => { // Run the request through the lambda-api framework return await api.run(event, context); };

Debug

Known issues

breakingVersion 1.0.0 migrated to AWS SDK v3. If your application uses `lambda-api`'s S3 service functionality, you must ensure `@aws-sdk/client-s3` and `@aws-sdk/s3-request-presigner` (peer dependencies) are installed and your code is updated for SDK v3 syntax.

fix

Install `@aws-sdk/client-s3` and `@aws-sdk/s3-request-presigner` via npm/yarn. Update any AWS SDK v2 S3 calls to their equivalent AWS SDK v3 syntax. If you must use SDK v2, pin `lambda-api` to `0.12.0`.

affects: >=1.0.0

gotchaAs of v1.0.1, AWS SDK v3 packages (`@aws-sdk/client-s3`, `@aws-sdk/s3-request-presigner`) are peer dependencies. They are not bundled with `lambda-api` and must be explicitly installed if your application leverages `lambda-api`'s S3 service.

fix

Run `npm install @aws-sdk/client-s3 @aws-sdk/s3-request-presigner` (or `yarn add`) if you intend to use the S3 service provided by `lambda-api`.

affects: >=1.0.1

deprecatedUsers still relying on AWS SDK v2 should use `lambda-api@0.12.0`. Version 1.x and above are exclusively built for AWS SDK v3.

fix

If migrating to AWS SDK v3 is not feasible, restrict `lambda-api` to `0.12.0` in your `package.json` (`"lambda-api": "^0.12.0"`). Otherwise, upgrade your application's SDK usage to v3.

affects: >=1.0.0

securityA prototype pollution vulnerability in the `deepMerge` utility was fixed in version 0.11.2. This could potentially allow an attacker to modify properties of `Object.prototype`, affecting all objects in the application.

fix

Upgrade to `lambda-api@0.11.2` or any later version (e.g., `1.x.x`) to patch this security vulnerability.

affects: <0.11.2

Errors

Common errors & fixes

TypeError: Cannot read properties of undefined (reading 's3') OR TypeError: api.s3 is not a function

The built-in S3 service functionality is being accessed without the required AWS SDK v3 peer dependencies installed, or the `lambda-api` version is incompatible with the installed AWS SDK version.

fix

Ensure `lambda-api` is `v1.0.0` or higher, and install `@aws-sdk/client-s3` and `@aws-sdk/s3-request-presigner`. If using `lambda-api@0.12.0` for AWS SDK v2, ensure `aws-sdk` is installed.

ReferenceError: require is not defined in ES module scope

Attempting to use CommonJS `require()` syntax in an environment configured for ES Modules (e.g., `"type": "module"` in `package.json`).

fix

Change your import statement to `import lambdaApi from 'lambda-api'; const api = lambdaApi();`. Alternatively, ensure your file is treated as CommonJS (e.g., change file extension to `.cjs` or set `"type": "commonjs"` in `package.json`).

Error: Cannot find module 'lambda-api' or 'lambda-api/package.json'

The `lambda-api` package has not been installed or is not resolvable from the current working directory.

fix

Run `npm install lambda-api` or `yarn add lambda-api` in your project directory.

Upgrade

Version history

5.5.0latest on npm

Audit

Dependencies

@aws-sdk/client-s3optionalRequired if utilizing the built-in S3 service for operations like object handling or pre-signed URLs.

@aws-sdk/s3-request-presigneroptionalNecessary for generating pre-signed S3 requests when using the S3 service functionality.

Agent activity

6 hits · last 30 days

node

Resources

githubhttps://github.com/jeremydaly/lambda-api ↗

packagehttps://www.npmjs.com/package/lambda-api ↗

homepagehttps://lambda-api.com ↗