# @accordproject/concerto-core

> Core Implementation for the Concerto Modeling Language

Latest version **5.0.0** (published 2026-09-08) · Apache-2.0 license · 0 weekly downloads

## Install

```sh
npm install @accordproject/concerto-core
pnpm add @accordproject/concerto-core
yarn add @accordproject/concerto-core
bun add @accordproject/concerto-core
```

## Health

**Score 75/100 (B)** — status: active.

Positive: has types; esm support; no vulnerabilities; has provenance; recently updated; high maintenance score; high quality score.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 5.0.0 |
| Published | 2026-09-08 |
| First published | 2019-10-03 |
| Weekly downloads | 0 |
| License | Apache-2.0 |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Node | >=18 |
| Dependencies | 10 |
| Unpacked size | 4 MB |
| Known vulnerabilities | 0 (+1 in 1 direct dependencies) |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 204 |
| Author | accordproject.org |
| Maintainers | mttrbrts, dselman, dianalease |
| Keywords | schema, data model, verification |

## Links

- npm: https://www.npmjs.com/package/@accordproject/concerto-core
- Repository: https://github.com/accordproject/concerto
- Issues: https://github.com/accordproject/concerto/issues
- npm.io page: https://npm.io/package/@accordproject/concerto-core

## Dependencies (10)

- [rfdc](https://npm.io/package/rfdc.md) 1.4.1
- [uuid](https://npm.io/package/uuid.md) 11.0.3
- [yaml](https://npm.io/package/yaml.md) ^2.8.3
- [dayjs](https://npm.io/package/dayjs.md) 1.11.13
- [debug](https://npm.io/package/debug.md) 4.3.7
- [semver](https://npm.io/package/semver.md) 7.6.3
- [randexp](https://npm.io/package/randexp.md) 0.5.3
- [@accordproject/concerto-cto](https://npm.io/package/@accordproject/concerto-cto.md) 5.0.0
- [@accordproject/concerto-util](https://npm.io/package/@accordproject/concerto-util.md) 5.0.0
- [@accordproject/concerto-metamodel](https://npm.io/package/@accordproject/concerto-metamodel.md) ^3.17.0

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## Recent versions

- 5.0.0 (latest) — 2026-09-08
- 5.0.0-beta.3 (unstable) — 2026-09-08
- 5.0.0-beta.2 — 2026-09-08
- 5.0.0-beta.1 — 2026-09-04
- 4.2.0 — 2026-08-26
- 4.1.5 — 2026-06-08
- 4.1.4 — 2026-06-02
- 4.1.3 — 2026-05-25
- 4.1.2 — 2026-05-19
- 4.1.0 — 2026-05-08
- 4.0.3 — 2026-05-06
- 4.0.2 — 2026-04-29
- 4.0.1 — 2026-04-27
- 4.0.0 — 2026-04-21
- 4.0.0-beta.4 — 2026-04-21
- … 935 more at https://npm.io/package/@accordproject/concerto-core/versions

## README

# Concerto Core

Main library for Concerto models, model manager, JSON instance validation and serialization.

# Installation

```
npm install @accordproject/concerto-core --save
```

## License <a name="license"></a>
Accord Project source code files are made available under the Apache License, Version 2.0 (Apache-2.0), located in the LICENSE file. Accord Project documentation files are made available under the Creative Commons Attribution 4.0 International License (CC-BY-4.0), available at http://creativecommons.org/licenses/by/4.0/.

---
_Source: https://npm.io/package/@accordproject/concerto-core · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._