# aws/jsii

jsii allows code in any language to naturally interact with JavaScript classes. It is the technology that enables the AWS Cloud Development Kit to deliver polyglot libraries from a single codebase!

Repository: https://github.com/aws/jsii
Canonical: https://ross.abutalabs.com/products/jsii
Homepage: https://aws.github.io/jsii
Language: TypeScript
License: Apache-2.0
License Family: permissive
Topics: aws, node, cross-language, typescript, hacktoberfest
Last push: 2026-08-26T14:34:29+00:00

## Health v2 (maintenance only)
Score: 99/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 99, longevity 100
- inputs: {"age_days": 3255, "days_push": 7, "days_rel": 9, "gap_med": 13.5, "n_releases_24m": 37}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2866, forks 268 (observed 2026-08-28T04:07:26.680024+00:00)

## What it is
jsii is a toolchain that lets TypeScript class libraries be consumed natively from Python, Java, C#/.NET, Go, and JavaScript by generating idiomatic bindings for each target language. It is the technology behind the AWS CDK's polyglot libraries.

## Use cases
- generate python java and dotnet libraries from a typescript codebase
- build a cdk construct library for multiple languages
- make my typescript sdk usable from python and java
- create polyglot infrastructure-as-code libraries
- cross-language bindings for a javascript class library

## When to choose
- you maintain a TypeScript library that must be published to multiple language ecosystems with identical APIs
- you are building AWS CDK constructs or similar developer/build tooling
- you want one source of truth for your API across languages

## When to avoid
- performance-sensitive or resource-constrained applications, due to JSON marshaling overhead and lack of distributed garbage collection
- you only need bindings for a single target language
- your API relies on JavaScript-specific runtime semantics that do not translate cleanly

## Facets
- artifact type: library
- maturity: active
- function: compiler, sdk, developer-tools
- domain: developer-tools, cross-platform, programming-languages, cloud-computing
- platform: python, jvm, dotnet, go, cross-platform
- tags: polyglot-bindings, aws-cdk, typescript-to-native, interop, code-generation, nodejs, typescript

## Member repositories
- aws/jsii (main) score 99

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:26.680024+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:36:06.481767+00:00, confidence not recorded.
  - readme: https://github.com/aws/jsii (fetched 2026-08-28T04:07:26.680024+00:00, sha ddc30bc0783c)
  - homepage: https://aws.github.io/jsii (fetched 2026-08-29T09:52:08.434741+00:00, sha 6205ae706e54)
- Data as of 2026-08-30T08:39:29.467469+00:00.