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peterpuzzle

43 karma · joined October 12, 2025

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peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. I sometimes advise people not to focus on today's date, but a date in the following week. Then you have more time to find a solution!
peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. I know, I know, the "rhombuses" are just rotated "squares", but I already had a calendar puzzle "Square", so that's why.
peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. Yes I did. Used some existing puzzles as inspiration. See https://praxispuzzles.com/calendar_puzzle_square
peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. If there is enough demand I can make a French version. Ordering a new batch of lasercut wood cost me $20, so I have a minimum batch size of 20.
peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. That puzzle started my search into this type of puzzle. But in the end my puzzle is harder, because it also contains the day of the week and has the most "irregular" puzzle pieces possible.
peterpuzzle··on Calendar Puzzle "Rhombus"
Actually I tried a lot of different combinations of piece shapes to find the "hardest" set of pieces that can still solve all possible dates. "Hard" is subjective, but I mean pieces with multiple protrusions.
peterpuzzle··on Calendar Puzzle "Rhombus"
I wrote 2 solvers in Python. One that loops through all possible dates and searches for a solution. And one that loops through all solutions and checks if they form a date or not. And luckily both gave the same answers.
peterpuzzle··on UnitTestGame
Learn to write effective unit tests using Test-Driven Development and Mutation Testing.

This game is written by me, a developer who wants better software. Good software is at least thoroughly tested by the developers. Testing software is a skill and this game helps you learn just that.

I am also a computer science professor at a university of applied sciences and I see many students and (junior) developers struggle with the concept of unit testing and writing enough (more then 1) and effective tests per unit (function). The game teaches them Boundary Value Analysis without mentioning it.

I am open for constructive feedback.

peterpuzzle··on Calendar Puzzle "Rhombus"
Creator here. No, you can arrange the puzzle pieces to make dates that don't exist, like Monday February 31. Actually there may be "impossible" dates, because I didn't check for them, but I guess all combinations of days of the week, day of the month and month are possible. And also many non-dates, like 1, 2, 3. But good point: alle possible dates have at least 1 solution. Disclaimer: I sell these puzzles for a little more than the raw material.
peterpuzzle··on The Flummoxagon
Fixed. On some puzzle pieces there is still a small offset in Firefox, but I can't find the reason...
peterpuzzle··on The Flummoxagon
I sometimes advise people not to focus on today's date, but a date in the following week. Then you have more time to find a solution!
peterpuzzle··on The Flummoxagon
You are right. This puzzle started my search into this type of puzzle. But in the end my puzzle is harder, because it also contains the day of the week and has the most "irregular" puzzle pieces possible.
peterpuzzle··on The Flummoxagon
You can arrange the puzzle pieces to make dates that don't exist, like Monday February 31. Actually there may be "impossible" dates, because I didn't check for them, but I think all combinations of days of the week, day of the month and month are possible.
peterpuzzle··on The Flummoxagon
Yes, I do ship to the US.
peterpuzzle··on The Flummoxagon
Recently I designed a calendar puzzle with 10 tetris-like pieces. When you place all the puzzle pieces on the board, three squares/rhombuses are still open and together they form a date. Can you arrange the puzzle pieces in such a way that it shows todays date? See https://praxispuzzles.com/calendar_puzzle_rhombus Disclaimer: I sell these puzzles for a little more than the raw material.