{{DATA:SCREEN:SCREEN_8}}
terminal SYSTEM STATUS: OFFLINE

Stop Solving Puzzles.
Start Fixing Real Outages.

An open-source, chaos-driven CLI harness that tests your engineering skills inside local, disposable Docker environments.

$ uv tool install yanju
Copied!
travel_explore Browse Scenarios
yanju-terminal
yanju@host:~$ yanju play official/nginx-upstream
[ INFO ] Initializing chaos scenario: Nginx Upstream 504...
[ INFO ] Provisioning local Docker environment...
[ INFO ] Network isolated. Injecting latency payload...
WARN: Connection timeout to upstream server at 10.0.0.5
ERROR: 504 Gateway Time-out
Task: Diagnose and fix the upstream configuration.
Time remaining: 14m 59s
root@scenario-container:~# tail -f /var/log/nginx/error.log

Core Philosophy

lock

100% Local & Private

Runs entirely on your local Docker engine. No sign-ups, accounts, or telemetry required.

terminal

Chaos-Driven

Scenarios aren't static puzzles. They actively break themselves to simulate real-world incidents.

source

Git Native

Run any community or internal scenario directly from public or private Git URLs.

4-Step Quickstart

# 1. Install CLI
$ uv tool install yanju
# 2. Preflight Check (Docker running?)
$ yanju check
# 3. Launch a Scenario
$ yanju play official/nginx-upstream
# 4. Verify your fix
$ yanju verify