- Assertion testing
- Asynchronous context tracking
- Async hooks
- C++ addons
- C/C++ addons with Node-API
- C++ embedder API
- Child processes
- Command-line options
- Deprecated APIs
- Diagnostics Channel
- File system
- Modules: CommonJS modules
- Modules: ECMAScript modules
- Modules: Packages
- Performance hooks
- Query strings
- Single executable applications
- String decoder
- Test runner
- Trace events
- Web Crypto API
- Web Streams API
- Worker threads
Table of contents
About this documentation#
Welcome to the official API reference documentation for Node.js!
Throughout the documentation are indications of a section's stability. Some APIs are so proven and so relied upon that they are unlikely to ever change at all. Others are brand new and experimental, or known to be hazardous.
The stability indices are as follows:
Experimental features are subdivided into stages:
- 1.0 - Early development. Experimental features at this stage are unfinished and subject to substantial change.
- 1.1 - Active development. Experimental features at this stage are nearing minimum viability.
- 1.2 - Release candidate. Experimental features at this stage are hopefully ready to become stable. No further breaking changes are anticipated but may still occur in response to user feedback. We encourage user testing and feedback so that we can know that this feature is ready to be marked as stable.
Features are marked as legacy rather than being deprecated if their use does no harm, and they are widely relied upon within the npm ecosystem. Bugs found in legacy features are unlikely to be fixed.
Use caution when making use of Experimental features, particularly when authoring libraries. Users may not be aware that experimental features are being used. Bugs or behavior changes may surprise users when Experimental API modifications occur. To avoid surprises, use of an Experimental feature may need a command-line flag. Experimental features may also emit a warning.
|Async hooks||(1) Experimental|
|Asynchronous context tracking||(2) Stable|
|Child process||(2) Stable|
|Diagnostics Channel||(2) Stable|
|File system||(2) Stable|
|Modules: ||(1) .2 - Release candidate|
|Modules: CommonJS modules||(2) Stable|
|Performance measurement APIs||(2) Stable|
|Query string||(2) Stable|
|Single executable applications||(1) Experimental: This feature is being designed and will change.|
|String decoder||(2) Stable|
|Test runner||(2) Stable|
|TLS (SSL)||(2) Stable|
|Trace events||(1) Experimental|
|UDP/datagram sockets||(2) Stable|
|Web Crypto API||(2) Stable|
|Web Streams API||(1) Experimental.|
|WebAssembly System Interface (WASI)||(1) Experimental|
|Worker threads||(2) Stable|
.html document has a corresponding
.json document. This is for IDEs
and other utilities that consume the documentation.
System calls and man pages#
Node.js functions which wrap a system call will document that. The docs link to the corresponding man pages which describe how the system call works.
Most Unix system calls have Windows analogues. Still, behavior differences may be unavoidable.