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Calm night room with Luna asleep by the window

on-call · night shift · rain

404:SleepNot Found

A lo-fi developer incident game

Learn software engineering by surviving production.

PLAY FREE Watch the shift

The night · 01:13

A quiet room. Then the pager.

01 · Quiet

The room is calm.

Rain, a lamp, a mug. Pebble & Pine is a fictional home-goods marketplace, and tonight you are the on-call engineer.

02 · Page

Production breaks.

A monitor flips. Customers are stuck. Someone in Relay is already sure they know why.

03 · Evidence

You investigate.

Logs, traces, flags, deploys. The notebook keeps facts. Opinions stay opinions until the system agrees.

04 · Recovery

The system comes back.

A mitigation stops the bleeding. A real fix is the change you would still defend in the morning.

05 · After

Then you build the thing.

Engineering Lab is the other half of the night: design a system, send traffic, break it, and see why.

Workstation · healthy

Production is broken.

Logs are noisy. The dashboard is green. Customers disagree. Find what actually happened.

Pulse in the game, checkout-api failing

Relay incident channel in the game

Pulsecheckout error rate

0.2%

HEALTHY

The dashboard is green.

Pulse

Health, graphs, logs, traces. Green is a color, not a conclusion.

Relay

Team chat. People have theories. Theories are not evidence.

Switchboard

Feature flags and runtime config. A lot of flags start with TEMP_.

Deploy

What shipped, and when. Timing is a clue, not a verdict.

Notebook

The facts you have actually earned, plus the hypothesis you are willing to test.

Skymap

Services, dependencies, owners. Symptoms live here. Motives do not.

Wick

A local assistant. It names a tool, then separates confirmed, likely, and unknown.

Notebook

The incidents actually make sense.

Each night has a real root cause, an evidence chain, and at least one thing that looks guilty and is not.

You are investigating a system, not guessing a quiz answer.

likelyRoot cause
unknownEvidence chain
unknownRed herrings
unknownLogs
unknownTraces
unknownConfig
unknownDeployments
unknownMitigation
unknownPermanent fix

Engineering Lab

Build it.
Break it.
Understand why.

Blueprint is a small architecture you can actually run. Traffic goes up. The queue rises. Latency follows. Then you change the drawing.

Client—Load balancer—API—Queue—Worker—Database

Queue is hot. Latency follows. Change the drawing and run it again.

Open the Engineering Lab page

Tracks · System Design

Learn modern engineering by touching it.

These are interactive scenarios. There is no lecture track, no certificate, and no claim that a night shift replaces the job.

System Design

Shape a path, then watch traffic move through it. A cache is a decision, not a sticker.

Distributed Systems

Retries, duplicates, ordering, and the charge that may have already happened.

Backend & API Design

How a request should behave. Not how to spell JSON.

Cloud Architecture

Scale, regions, and rollouts, without a vendor logo quiz.

Production Engineering

Alerts, deploys, and the difference between a graph and a customer.

AI Engineering

Agents, retrieval, tools, cost, and evals. Still just software.

Wick // online

AI systems are still software systems.

Players practice agents that call tools, retrieval that can be stale, and a bill that arrives because a loop did not stop.

Agentretry

Waiting on a tool.

Pebble & Pine · internal

Every night shift needs company.

Change hair, clothes, and glasses. Companions are company, not the job. Luna sleeps near the desk until the room stops being quiet.

The game's companion picker showing Luna, a German Shepherd, asleep

Luna

German Shepherd

Mostly asleep. Immediately awake when production isn't.

Honey

Golden Retriever

Treats every quiet minute like you just got home.

Pip

Corgi

Patrols the rug. The rug has accepted this.

Maple

Beagle

Follows footsteps. Dashboards are a distant second.

Ink

Black Cat

Keeps the window seat. The rain can have the rest.

Biscuit

Tabby Cat

Desk-adjacent. On-call was not in the job description.

Moth

Tuxedo Cat

Dressed for the night shift. Does not take the pager.

Public alpha

What you can play tonight.

The public release is a real slice of the game, not the whole campaign.

Campaign Nights 1–2
Daily Incident
Quick Shift
Character customization
Selectable companions
Wick, the local assistant
A System Design sample
A Distributed Systems sample
An AI Engineering sample
A starter Sandbox

Read the alpha notes

Works in staging.

Production is a testing environment. Apparently. The public build does not pretend otherwise.

Releases

The night shift continues.

More incidents and labs will arrive in content drops. There is no published calendar.

Now

Public alpha

Nights 1 and 2, a daily incident, a quick shift, and sample labs. This is the build you can play.

Later

The rest of the campaign

A larger campaign already exists. It will arrive in episodic drops, along with more labs. No schedule is published.

Preview

Private preview.

Private preview testers may receive full-build access. There is no public signup on this site. If you were invited, the game itself is where that access lives.

Play

Play in browser.

Browser

Windows

Coming soon

macOS

Coming soon

Mobile

Coming soon

Capture Mode

Watch the shift.

The game can record a quiet room, an incident, and the lab. This spot plays that reel when one is published.

CaptureNight 1 · checkout

The game room when the pager hits: rain, a red monitor, and the checkout alert

The night room

Rain on the glass. The lamp is the warmest thing in the building.

The desk

Pulse is loud. The dashboard is not the incident.

The lab

Draw the path. Add traffic. Watch the queue admit what the diagram hid.