RubySquare
Minimal-move solving & parity tricks
Why some boards refuse to be solved in an even number of moves — and how to spot the impossibles before you burn twenty rotations.
Journal
Notes from inside the grid.
Solving technique, design essays, community stories and the occasional math rabbit hole — written by the team that builds the boards.
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Design
Community
Theory
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From the desk
The 15-minute brain ritual
A sustainable daily routine that turns casual tapping into real board vision — the same warm-up competitive solvers use.
A parent's guide to logic puzzles
Why spatial puzzles outperform worksheets for kids' reasoning — and how to introduce Ruby Square without it becoming homework.
Behind the glass: designing a puzzle
How a 64-square board gets authored — the golden-ratio rules, the solvability checker, and why level 612 took eleven drafts.
Colorblind design done right
8% of male players can't tell ruby from teal. How the palette got rebuilt to work for every eye — without dulling the colors.
Surviving the Extreme marathon
Stage 8 is 150 boards of 4x4 blocks and six-color chaos. The training plan from players who've finished it — twice.
More from the archive
Deeper cuts
Hidden patterns & the history of symmetry
From Byzantine mosaics to Conway's Game of Life — where Ruby Square's pattern language comes from.
Move economy for speed solvers
Undo less, plan more. The efficiency habits that turn a 40-move solver into a 20-move solver in three weeks.
Training away from the screen
Paper drills, dice exercises and mental rotation games that build the same skills — no battery required.
Monthly dispatch
The Ruby Memo
One email a month: new stages, technique deep-dives and community records. No noise, unsubscribe any time.
Staff shelf
What the team re-reads
01
Parity tricks — the math that separates
lucky solvers from deliberate ones.
02
The Extreme marathon — required reading
before stage 7.
03
Designing a puzzle — the design team's own
favourite explainer.
04
Kids & logic — passed around every
school email thread.
05
Offline-first engineering — why the app
works in a tunnel.
Reading about puzzles made me better at them. Playing puzzles made me better at thinking. The blog is where those two meet.
Jules M. — community moderator & contributor, Lyon
Blog FAQ
About this journal
The design and dev team, plus invited community contributors — moderators, top-100 solvers, educators who use the game in class.
Roughly twice a month, plus extra posts when a new stage ships or a community record falls.
Yes — pitch us via contacts with "guest post" in the subject. Technique pieces and classroom stories are always welcome.
The newsletter is the canonical feed — new posts land there first, before any social push.
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