Yeast
Yeast turns a folder into real Linux VMs.
Define machines in yeast.yaml, run yeast up, and get SSH-ready QEMU/KVM guests with cloud-init, provisioning, snapshots, private networking, Docker-style service port forwarding, and JSON output for automation.
Learn Yeast In Order
If you are new, follow this path. It is ordered so each page teaches one layer before the next one.
| Step | Read | You learn |
|---|---|---|
| 1 | What Is Yeast? | What problem Yeast solves |
| 2 | Installation | How to get the CLI and check your host |
| 3 | Quickstart | The shortest working loop |
| 4 | Write yeast.yaml |
How to edit RAM, CPU, disk, image, users, provisioning, networking, and forwarded ports |
| 5 | First VM | A slower first-machine walkthrough |
| 6 | Yeast Labs | Guided tutorials that build confidence |
The Short Version
Run these commands from a new project folder:
When you are done:
yeast up downloads supported cloud images automatically when they are missing.
The File You Edit Most
Most Yeast work happens in yeast.yaml.
This small file says what machines you want:
version: 1
instances:
- name: web
image: ubuntu-24.04
memory: 1024
cpus: 1
disk_size: 20G
ports:
- "8080:80"
Common edits:
| Want to change | Edit |
|---|---|
| RAM | memory: 2048 |
| CPU count | cpus: 2 |
| disk size | disk_size: 30G |
| image | image: debian-12 |
| VM name | name: web |
| host SSH port | ssh_port: 2222 |
| guest web app on your laptop | ports: ["8080:80"] |
With that ports example, yeast up and yeast status print a host URL you can open directly, such as http://127.0.0.1:8080.
Read Write yeast.yaml when you want to understand every field without jumping straight into reference docs.
What Yeast Handles
- project-local VM definitions with
yeast.yaml - trusted image discovery and caching
- QEMU/KVM startup
- cloud-init seed generation
- SSH readiness
- package, file, and shell provisioning
- stopped-VM snapshots and restore
- one private lab network per project
- Docker-style host-to-guest service forwarding with
instances[].ports - guest control with
ssh,exec,copy,logs, andinspect - stable JSON output and lifecycle events
What Yeast Is Not
Yeast is not a cloud platform, container orchestrator, web dashboard, or replacement for Kubernetes.
It is a Linux-first local VM engine for repeatable real-machine labs.
Current Release
The current docs target Yeast v1.1.4.
Start with Quickstart, or jump to the command reference.