# kmackay/micro-ecc

ECDH and ECDSA for 8-bit, 32-bit, and 64-bit processors.

Repository: https://github.com/kmackay/micro-ecc
Canonical: https://ross.abutalabs.com/products/micro-ecc
Language: PHP
License: BSD-2-Clause
License Family: permissive
Last push: 2024-11-14T03:34:49+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4868, "days_push": 657, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1432, forks 511 (observed 2026-08-28T04:04:43.176858+00:00)

## What it is
A small, fast C library implementing ECDH key exchange and ECDSA signatures for 8-bit, 32-bit, and 64-bit processors, with optional inline assembly for AVR, ARM, and Thumb. It uses no dynamic memory allocation, resists known side-channel attacks, and supports five standard NIST/SEC curves.

## Use cases
- add elliptic curve cryptography to an Arduino or AVR microcontroller project
- implement ECDH key exchange on an embedded device with limited memory
- verify ECDSA signatures on an 8-bit or 32-bit microcontroller
- secure IoT device communication without dynamic memory allocation
- use secp256r1 or secp256k1 in a bare-metal C project
- add side-channel-resistant public-key crypto to firmware

## When to choose
- you need ECDH or ECDSA on resource-constrained embedded hardware
- you want a tiny, dependency-free C library with no heap usage
- you target AVR, ARM, or Thumb platforms and want optimized assembly
- you need side-channel-resistant elliptic curve operations

## When to avoid
- you need RSA or other non-elliptic-curve cryptography
- you want a full TLS stack rather than raw ECDH/ECDSA primitives
- you need curves beyond the five supported ones
- you prefer a high-level managed-language crypto library

## Facets
- artifact type: library
- maturity: maintenance
- function: cryptography, security, embedded
- domain: security, embedded-systems, privacy
- platform: embedded, cpp, c, cross-platform, iot
- tags: ecc, ecdh, ecdsa, elliptic-curve, arduino, microcontroller, no-dynamic-allocation, side-channel-resistant

## Member repositories
- kmackay/micro-ecc (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:43.176858+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 2026-08-30T04:37:02.083733+00:00, confidence not recorded.
  - readme: https://github.com/kmackay/micro-ecc (fetched 2026-08-28T04:04:43.176858+00:00, sha 6dc943ae31e3)
- Data as of 2026-08-30T08:39:29.467469+00:00.