Install Fiji

The fastest way to install Fiji and its required Wasmtime runtime:

curl -fsSL https://fiji.dev/install.sh | sh

The installer detects whether a supported Wasmtime is already on your PATH and only installs one if needed.

Manual install

If you'd rather manage WebAssembly runtimes yourself:

1. Install Wasmtime (wasmtime.dev) at a supported major version.
2. Download the Fiji release tarball from Releases.
3. Extract the tarball and add bin/fiji to your PATH.

Fiji works with any installation method that puts wasmtime on PATH at a supported version.

Using wvm

For users who want a dedicated WebAssembly runtime manager, we recommend wvm. Fiji's installer uses it when needed, but Fiji itself does not depend on it at runtime — fiji doctor only checks for wasmtime.

To opt out of the installer's automatic wvm acquisition, set FIJI_NO_WVM=1 and the installer will print manual instructions instead.

Configuration

The installer respects the following environment variables:

Variable	Default	Meaning
FIJI_PREFIX	~/.fiji	Install directory
FIJI_WASMTIME_VERSION	(latest supported)	Required Wasmtime major version
FIJI_NO_WVM	(unset)	Set to 1 to never auto-install wvm

Verify your installation

fiji --version
fiji doctor          # check whether the host has a supported Wasmtime
fiji verify-release  # run the release verification floors

fiji doctor reports the resolved Wasmtime version, the install prefix, and any actionable gaps. fiji verify-release runs the release's verification floors against the artifacts shipped in the tarball.

What you get

Command	What it does
fiji --version	Print release version
fiji doctor	Diagnose host Wasmtime availability
fiji verify-release	Run release verification floors
fiji manifest	Emit MANIFEST.json
fiji wit	Emit the public WIT

Next: Hello, Fiji.