Install the CLI
Get the nebula command-line tool and the prerequisites for running a mesh locally.
The nebula CLI is the front door to Nebula: it installs the middleware into a Unity project, builds the player, runs the whole mesh on your machine and deploys it to a cloud provider. It is one self-contained executable (no .NET runtime needed) built from cli/Nebula.Cli, and it works the same on Windows, macOS and Linux.
Prerequisites
| What | Why | Notes |
|---|---|---|
| Unity 6 (6000.x) | Nebula is a Unity project; every role is the same player build | Developed on 6000.6. Add the Linux Dedicated Server module to deploy to the cloud. |
| SpacetimeDB CLI | Runs the local control plane and publishes the module | nebula setup installs it with the official installer. |
| .NET 10 SDK | Compiles the control-plane module (and the CLI itself, when built from source) | nebula setup installs it into ~/.dotnet if missing. |
| git, ssh | nebula init fetches the SDK; nebula deploy reaches the VMs | Only needed for those two commands. |
Install
iwr https://windows.nebula.1by3.co -useb | iexThe installer puts nebula.exe in ~/.nebula-cli/bin and adds that folder to your user PATH. Open a new terminal afterwards.
Hosted installer URLs
The hosted URLs are not live yet. Until they are, install from a checkout, or use the installer scripts in cli/install/ with -Archive/--archive <file> pointing at a release archive built by cli/scripts/package.ps1 or package.sh. Without either, the scripts download nebula-<version>-<rid>.zip or .tar.gz from the repository's releases; NEBULA_VERSION picks a version and NEBULA_RELEASE_BASE another host.
Check the install and set up prerequisites
nebula --version
nebula setupnebula setup installs what is missing and reports what it finds: the SpacetimeDB CLI, a .NET 10 SDK, git and ssh, and the Unity editors Unity Hub has installed (with whether they include Linux Dedicated Server support). nebula setup --check only reports. nebula setup --yes answers every prompt with yes.
Environment variables
| Variable | Effect |
|---|---|
NEBULA_SOURCE | A checkout of the Nebula repository for the installer to build from, and for nebula init to copy Packages/com.1by3.nebula from. |
NEBULA_UNITY | Path to the Unity editor executable (or the Hub's Editor folder) nebula build should use. nebula config unity stores the same thing. |
NEBULA_CLI_HOME | Where the CLI keeps its binary, config and scratch builds (default ~/.nebula-cli). |
HCLOUD_TOKEN | Hetzner Cloud API token; always takes precedence over the one stored by nebula config hetzner, so CI can deploy without a config file. |