# jerryscript-project/jerryscript

Ultra-lightweight JavaScript engine for the Internet of Things.

Repository: https://github.com/jerryscript-project/jerryscript
Canonical: https://ross.abutalabs.com/products/jerryscript
Homepage: https://jerryscript.net
Language: C
License: Apache-2.0
License Family: permissive
Topics: javascript-engine, javascript, jerryscript, internet-of-things, iot, runtime
Last push: 2025-10-08T17:35:32+00:00

## Health v2 (maintenance only)
Score: 44/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 46, release rhythm 8, longevity 100
- inputs: {"age_days": 4171, "days_push": 329, "days_rel": 623, "gap_med": null, "n_releases_24m": 1}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 7418, forks 691 (observed 2026-08-28T04:09:59.767923+00:00)

## What it is
JerryScript is an ultra-lightweight JavaScript engine written in C99 for resource-constrained devices like microcontrollers, running in under 64 KB RAM and 200 KB flash. It offers full ECMAScript 5.1 compliance, partial ES2025 support, snapshot precompilation, and a mature C API for embedding.

## Use cases
- run JavaScript on microcontrollers with limited RAM
- embed a scripting engine in a C application
- control IoT device peripherals from JavaScript
- precompile JavaScript to bytecode snapshots for small devices
- add scripting to firmware on ARM Cortex-M devices

## When to choose
- targeting devices with <64 KB RAM and <200 KB flash
- you need an embeddable, portable C99 JavaScript engine
- on-device compilation and execution of scripts is required

## When to avoid
- you need full modern ECMAScript compliance
- building server-side or browser JavaScript applications
- your device has ample memory for V8 or other full engines

## Facets
- artifact type: library
- maturity: maintenance
- function: interpreter, embedded
- domain: embedded-systems, iot, programming-languages, hardware
- platform: embedded, iot, cross-platform, c
- tags: javascript-engine, ecmascript, microcontrollers, c99, snapshot, embeddable, linux

## Member repositories
- jerryscript-project/jerryscript (main) score 44

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:59.767923+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 2026-08-29T17:37:45.890594+00:00, confidence not recorded.
  - readme: https://github.com/jerryscript-project/jerryscript (fetched 2026-08-28T04:09:59.767923+00:00, sha cdebb81bec94)
  - homepage: https://jerryscript.net (fetched 2026-08-29T08:33:18.700817+00:00, sha 0836eec76c9c)
  - site_page: https://jerryscript.net/getting-started (fetched 2026-08-29T08:33:18.703332+00:00, sha bea67d4dcca0)
- Data as of 2026-08-30T08:39:29.467469+00:00.