Nix owns the stack
rig compose is nix build. Layers and agents are flakes. The CLI does not merge files by hand.
SlopKit Rig
Stack layers. Attach the session.
An agent is an ordered stack of layers. Nix builds the home.
The runtime keeps that session on a relay.
rig attach opens a PTY into it. Your laptop does not
have to be the machine that ran the build.
curl -fsSL https://rig.slopkit.dev/install.sh | bash
session · deepwriter
$ rig session create --agent deepwriter --prompt "hello" creating session deepwriter root /nix/store/…-deepwriter-root $ rig attach deepwriter
Named sessions
rig attach review-mr-42 works from another machine. The supervisor holds the PTY.
Cache, not a tarball
Publish uploads a Nix binary cache plus a card at name@tag. Shared store paths land once.
How it runs
Same agent definition locally and on the relay. Only the runtime changes.
Layers
A layer declares skills, MCP, packages, sandbox, secrets, hooks. Later layers override. Mergeable paths like AGENTS.md concatenate.
Agent
An agent is a stack. Every stack starts with base. You do not list it. nix build .#default -o .agent materializes the home.
Publish
rig push repo.slopkit.dev/deepwriter:latest writes the cache and the card. Pull is anonymous HTTPS.
Session
The runtime realizes the root, starts MCP inside it, and waits. rig shell and rig attach enter that box.
The CLI and the runtime
Keep the boundaries. One binary does not do all of this.
rig
Compose, inspect, pull, push, talk to a running runtime. It does not embed the supervisor.
runtime
Sessions, TLS API, ACP, attach. nix backend today. Firecracker when you want a snapshot.
Want a session that is not on your laptop?
Install the CLI, point it at a runtime, pull an agent, create a named session. Start has the commands.