Node.js
N-API
Learn to write native addons with N-API.
What is N-API?
N-API is the stable application programming interface (API) Node.js offers for writing C/C++ code. N-API provides a contract that does not change across Node.js versions, so a native addon written once runs on many Node.js versions.
Historically addons depended directly on V8 headers; when V8 updated the addon broke. N-API removes this dependency: you write N-API calls and Node.js translates them to V8 internally. A napiModule(name) function models this idea: it returns {name: name, api: 'N-API', version: 9}. N-API version 9 ships with Node.js 22. This abstraction greatly reduces addon maintenance.
The N-API module
An N-API module is a registration function that returns an object to the JS side. napiModule(name) models this: it returns the name, API name and version. In real N-API this is written in C; here we model it in JS.
Example: function napiModule(name) { return {name: name, api: 'N-API', version: 9}; }. napiModule('myaddon') returns {name: 'myaddon', api: 'N-API', version: 9}. console.log(napiModule('myaddon').api + ' v' + napiModule('myaddon').version) prints N-API v9. This is a simple model of N-API module registration; real registration uses the NAPI_MODULE macro but the idea is the same: a name and a set of exports.
Exercise Write the N-API module
Write function napiModule(name). Return {name: name, api: 'N-API', version: 9}. Print console.log(napiModule('myaddon').api + ' v' + napiModule('myaddon').version).
Show example solution
function napiModule(name) {
return {name: name, api: 'N-API', version: 9};
}
console.log(napiModule('myaddon').api + ' v' + napiModule('myaddon').version);
Test yourself
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What does N-API solve?
- Low memory usage
- Addon compatibility across versions
- Otomatik testi
- Faster network requests
Show answer
Addon compatibility across versions — N-API keeps addons compatible across Node.js versions.
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Return the N-API version
function napiModule(name) { return {name: name, api: 'N-API', version: ____}; }
Show answer
function napiModule(name) { return {name: name, api: 'N-API', version: 9}; }
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Match each concept to its description
- N-API
- Stable addon interface
- V8
- JavaScript engine
- addon
- C/C++ extension
- Node.js 22
- Ships with N-API v9
Next lesson: node-addon-api
