Sort the shelves. Mind the tall volumes.
A hyper-casual book sort puzzle for phones. Tap a shelf to lift the books on its end and tap where they go; fill a shelf with one colour and it is shelved. Some volumes are tall and only a few shelves have room for them, so a set with an atlas in it has to finish on a tall shelf. Later chapters add a returns cart you can only take from and locked cases that open when a colour is finished.
I designed the rules, the three mechanics, 40 levels in four chapters and the look on a professional free UI kit. A generator deals the levels to my specs, a solver proves every par, and a level is kept only if its newest mechanic changes the best line.
Play in your browserRead the GDDOne-pagerEach part below condenses one chapter of the game design document. Every summary ends with a link to the full chapter in the PDF.
Look, lift, place, finish. Books go onto the same colour or an empty shelf; a full shelf of one colour turns gold. No timer and no fail: stars reward the fewest moves, a hint shows the solver's next move, and restart is free.
Shelves are low or tall, and any run with a tall volume in it fits only on a tall shelf. The returns cart only gives and must end empty. A locked case holds books nobody can touch until a shelf of its tag's colour is finished; then the padlock pops off.
Read the full chapter in the GDD (page 2)The shelves; bigger collections; the returns cart; locked cases and everything together. Within each chapter the best line climbs in a sawtooth, from 3 to 12 moves across the game, with a breather after the peaks. A one-line tip appears only where an idea is new.
Read the full chapter in the GDD (page 3)I write each level as a spec: shelves, colour sets with their tall volumes, a range for its par and its focus, the newest mechanic. A generator deals the books and keeps a deal only if nothing starts finished, the par is in range and switching the focus off changes the best line. Tests check every par.
Read the full chapter in the GDD (page 4)Heights per colour did nothing, and an empty reserved shelf was decoration; both were redesigned. Bots found the height rule's real job: careless play dead-ends, so the game now says so and points at restart. Shelf Life has not been playtested by people yet, and the document lists what only they can show.
Read the full chapter in the GDD (page 5)Lifted runs rise, books fly home in an arc, a finished shelf turns gold and its books hop, and a case opens with a pop. The interface is SunGraphica's Casual Mobile Game UI Kit. A monetisation plan (not built), the first KPIs to measure, and a roadmap close the document.
Read the full chapter in the GDD (page 6)Every image is captured from the game itself.
Built with an AI coding assistant (Claude). I designed the game, set the rules, the chapter plan and the tuning, and reviewed every build. Interface: Casual Mobile Game UI Kit by SunGraphica; sounds by Kenney; Montserrat.