Entry Points

#Reference

Seven subpaths. Each loads only what it needs.

import from	what you get
`mountx/auto`	start here — `mount()`, which picks the transport for this host
`mountx`	the driver types, capabilities, errors, path helpers, loopback
`mountx/drivers/memory`	a ready-made in-memory filesystem
`mountx/drivers/node-fs`	a ready-made passthrough to a real folder
`mountx/drivers/unstorage`	an adapter over any unstorage `Storage`
`mountx/fuse`	the FUSE transport on its own, if you want to pin it
`mountx/nfs`	the NFSv3 transport, and `createNfsServer()`

The three mountx/drivers/* subpaths are documented in the guide, beside the interface they implement: built-in drivers. mountx/auto and the two transport subpaths are documented in Transports, beside the protocols they speak.

Plus the mountx CLI, which the package installs as a binary — a demo and a test bench, documented in the guide.

#The `mountx` root export

Everything that is not a transport, over the five pages of this section. No transport code is reachable from here, so import … from "mountx" costs nothing but the types and a few small functions.

page	what is on it
Driver interface	`FsDriver`, `StatsLike`, `DirentLike`, `StatsFsLike`, `FileHandleLike`, the `S_IF*` bits
Capabilities	`FsCapabilities`, `resolveCapabilities()`, the `mountx.*` extension namespace
Errors	`fsError()`, `isFsError()`, `errnoOf()`, `ERRNO_CODES`, `rangeError()`
Loopback harness	`createLoopback()` — the driver without a kernel
Paths and locking	`normalizePath()` and friends, `PathLock`

#What to import

mountx/auto is the one to reach for unless you have a reason not to. It works out what this host can mount with and hands back that transport's own mount object, tagged.

import { mount } from "mountx/auto";
import { createLoopback } from "mountx";
import { createMemoryDriver } from "mountx/drivers/memory";

Each subpath loads only what it needs. mountx/auto reaches a transport through await import(), so choosing FUSE never loads the NFS stack — and its probe reaches only the two cheap host checks, neither of which pulls in a protocol codec.

Note

mount is deliberately not re-exported from the root mountx. Doing so would pull the protocol layer, the session and node:child_process into every import … from "mountx" — around 90 kB — for a name that has to be chosen between transports anyway.

#Type-level guarantees

Two rules the type system holds, and both are checked in CI:

FsDriver is a subset of node:fs/promises. The acid test is const driver: FsDriver = await import("node:fs/promises"), which must compile with no cast.
AutoMount is a discriminated union. Narrowing on mounted.transport reaches everything that transport has, with no cast and no optional chaining.

#Platform support

	Linux	macOS	Windows
`createLoopback`	✅	✅	✅
`createNfsServer`	✅	✅	✅
`mount` (FUSE)	✅	—	—
`mountNfs`	✅ root	✅ no root	—
`mount` (auto)	✅ FUSE	✅ NFS	—

Everything in mountx/fuse except mount.ts, and everything in mountx/nfs except server.ts/mount.ts, is pure data transformation and runs anywhere.

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