pub package package publisher

A generic file system abstraction for Dart.


Like dart:io, package:file supplies a rich Dart-idiomatic API for accessing a file system.

Unlike dart:io, package:file:

  • Can be used to implement custom file systems.
  • Comes with an in-memory implementation out-of-the-box, making it super-easy to test code that works with the file system.
  • Allows using multiple file systems simultaneously. A file system is a first-class object. Instantiate however many you want and use them all.


Implement your own custom file system:

import 'package:file/file.dart';

class FooBarFileSystem implements FileSystem { ... }

Use the in-memory file system:

import 'package:file/memory.dart';

var fs = MemoryFileSystem();

Use the local file system (requires dart:io access):

import 'package:file/local.dart';

var fs = const LocalFileSystem();


A file system that provides a view into another FileSystem via a path.
Core interfaces containing the abstract FileSystem interface definition and all associated types used by FileSystem.
A local file system implementation. This relies on the use of dart:io and is thus not suitable for use in the browser.
An implementation of FileSystem that exists entirely in memory with an internal representation loosely based on the Filesystem Hierarchy Standard.