The city sleeps. One post office stays lit.

Every letter has a destination, but not a private route. Connect the conveyor belts and choose departure times for A, B and C. When two letters need the same crossing, decide who goes first and who waits a moment.

As the night progresses, docks accept mail at specific ticks. Holding shelves, switches and timed gates bring new challenges. Route length, waiting time and departure delays all shape when each letter arrives.

One post office. One hundred puzzles.

Work through 100 scheduling puzzles across 12 chapters, with new rules and delivery conditions introduced along the way.

There is no real-time countdown. Plan at your own pace, advance one tick at a time, or rewind to examine what happened. Two levels of hints and optional route diagnostics help you understand where your current plan goes wrong.

A feathered friend for the night shift

Your postal bird celebrates success with a cheerful chirp and a flight around the post office. When a delivery goes wrong, your little companion is there for another try.

Gentle music and playful sound effects bring warmth to every shift.

Play at your own pace

• Separate music and sound effects volume controls.

• Reduced animation option.

• Automatically saved routes, completion records and settings.

• English, Traditional Chinese and Simplified Chinese.

• Keyboard and mouse controls.

Stamp the completed shift and hand over the last mailbag. By dawn, someone in the city has received the message they were waiting for.