A generated code takes away half the game. Whether to repeat a colour,
whether to leave one out, whether to do the thing this opponent will not
expect — those are real decisions, and no random number generator makes
them.
So a game now opens in a SETTING phase: each player chooses the code
their opponent will have to break, one after the other, and the guessing
starts once both are down. They choose in turn rather than at once
because the engine only ever has one seat on the clock, and it costs
nothing — neither can see the other's, so going second is not an
advantage.
The same move carries both: while the codes are being set it is your
code, and after that it is a guess at theirs. Which one it means comes
from the phase rather than from a flag on the move, because the phase is
the thing that actually knows — a flag could disagree with it.
An empty code used to mean one thing and now means two — not chosen yet,
or chosen and hidden from the device this copy was sent to — so the
state carries a flag per player. Whether the other player is ready is
not a secret, and a screen has to be able to say "waiting for them"
rather than sit blank.
The computer sets a code at random and does not try to be clever about
it: a code chosen to beat a particular solver has a pattern in it, and a
pattern is the one thing a code should not have. That single choice is
the only random in the app drawn from a source nobody else can see —
every other one is seeded from the position so a host and a client
agree, but a code seeded from anything on the wire could be worked out
by the player who is meant to be guessing it.
A code set on a guest's device reaches the host as a move and stops
there: moves are intents sent to the host and are never relayed to the
other player, so the only copy that reaches an opponent is redacted.
Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_019Pr6B8xDDtJJcb6WJMw7Ud
The four games that were listed but not written. Nothing in the
catalogue is marked "coming soon" any more.
Checkers is English draughts on the thirty-two dark squares, numbered
the way the game is written down. Captures are compulsory and a multiple
jump is one move object, so a player cannot stop halfway through one —
true by construction rather than by a rule that has to be enforced
somewhere. The move generator matches the published perft counts at one
to four ply (7, 49, 302, 1469), which fold in compulsory capture,
crowning and the men's forward-only rule all at once.
Backgammon's hard rule is not how a checker moves but that a player must
use as much of the roll as they can, and that cannot be checked one move
at a time: a move can be illegal precisely because playing it strands
the other die. So the generator works backwards from whole turns —
memoised depth-first over the remaining dice — and offers only the first
steps of the longest plays. Recomputing it after each checker is what
makes the rule true by construction. Every die comes from the table's
seed and a count of rolls made, which is in the state rather than beside
it so a game is reproducible from what crosses the wire. There is no
doubling cube; the rules document says so plainly.
Mastermind is played as a duel — both players are set a code and both
are breaking one — because the pencil-and-paper game gives the codemaker
nothing to do. It ends at the foot of a round, never mid-round, or going
first would be worth half a guess. It is the one game here with anything
to hide, so viewFor does real work: the host sends each device only its
own code, and a device that was never given a code refuses to score a
guess against it rather than quietly answering "nothing".
Pirates and Bulgars is Sackson's theming of Asalto, and the rules
document is explicit about which parts are attested and which had to be
chosen — the book could not be obtained. Two hunters who take by
jumping against twenty-four who cannot take at all, on a thirty-three
point cross whose drawn lines come from the same adjacency table the
moves come from, so the board and the rules cannot disagree.
130 unit tests across the four engines, all run locally as well as in
CI: game/ has no Android in it, which is what makes that possible.
Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_019Pr6B8xDDtJJcb6WJMw7Ud
Claude