Every answer is checked.
No answer is guessed.
Riviera is a free daily backgammon puzzle: no ads, no sign-up. Here’s exactly how the positions, answers and explanations are made.
The puzzle
Every day there are three positions, easy to hard, the same for everyone. You get the board and the dice, and you build the move you think is best. Then you see your move next to the best one, what the difference cost, and the idea to remember.
Where the positions come from
Each one is a real mistake: a move that cost at least 8 points per 100 games, found in games played on Riviera and in thousands of simulated games. Positions are rated by how hard the best move is to find, not by how many moves there are.
Easy: a simple computer player, one that doesn’t look ahead, finds the best move, there are only a few real choices, and every other move costs at least 15 points per 100 games. Hard: that simple player misses it even when it looks a roll ahead, and another move comes within 15 points, so the right idea has a close rival. Medium is everything in between.
How each answer is verified
The top five candidate moves are rolled out over thousands of games with GNU Backgammon, using the same dice for every move so luck cancels out. A position is used only if the best move is clearly ahead (by at least 4 points per 100 games, and well beyond the rollout’s margin of error) and a deeper check agrees. If two moves are too close to call, the position is thrown out, or both count as correct.
Costs and win rates are for a single game played without the doubling cube, so they measure the checker play alone. A shot is any roll that can hit one of your checkers.
- Thousands of games per position
- Same dice for every move
- Near-ties thrown out
How the explanations are written
No chatbot writes them. Every sentence is built from facts measured on the two positions, and nothing else. For example:
“The best move hits on your 16-point, and leaves only 18 shots, against 33 for yours.”
Each highlighted fact is counted directly from the board or the rollout. Automated tests check that no sentence claims something the two positions don’t show.
What Riviera never does
No AI decides the answers or writes the explanations. (AI coding tools helped build the app itself; everything players see comes from rollouts and measured facts.) No ads, no paywall, no third-party trackers, and no selling your data. You can play without an account.
Found something wrong?
Open Show analysis on any position and tap Report a problem. Tell me what looks off and I’ll fix it.