Jev Arena

About the wall. Thirty-six games, one model, one API call per tick. Back to the wall · Contact · Harness notes.
checking server…

Thirty-six games, one call at a time

TypeSafe's Jev is a System One model: send it a state and typed questions, get back calibrated probabilities instead of text. The wall runs thirty-six real-time games, three across and twelve down, and a single column on a phone. Tiles that scroll out of view pause, so the cost in the bar is the cost of what you are looking at. In every one the code owns the rules, the physics and the enumeration of legal options with their facts; Jev makes the judgment call. Nothing in the loop reasons, plans or generates text. Every pending question from all nine games goes out in a single request roughly five times a second, and the bar at the top shows what that costs: about three cents a minute.

Snake

grid · turn-based · 4-8 players

Battlesnake rules. Every turn each snake gets a Choice over its legal moves, described by reachable space, food distance and which enemy heads can reach that square.

Agar

continuous · real-time

Code steers at 60 fps; Jev picks an intent a few times a second: graze, hunt something edible, or flee something that can eat you.

Tetris

combinatorial · quasi real-time

Every rotation and column simulated with consequences; Jev picks among the top candidates; the piece then falls into place like a human game.

Space Invaders

shooter · real-time

Up to three alien columns with their lowest alien and the move needed, plus dodge when a bomb is coming. Code drives and fires; Jev sets the priority.

Tron

grid · 4 personas

Every few cells each bike chooses a turn from reachable space, rival heads and pocket warnings.

Pong Duel

physics · 2 personas

Interception is exact; each paddle chooses the contact point from where the return would arrive relative to the opponent.

Qix

territory · risk

Each direction is a walk or a simulated cut: length, area gained, and how close the Qix is to the line.

Missile Command

prioritisation

Up to four warheads with time to impact, target city and blast coverage, plus hold.

Pinball

timing · physics

Flip left, flip right or hold, from a predicted arrival point and time at the flippers.

Tank Arena

combat · 3 personas

Attack a target, take cover, or advance, from line of sight, distance, facing and hit points.

Copter

cave flyer · real-time

Climb, hold or dive, each with the predicted position against the cave half a second and a second ahead.

Q*bert

hops · enemies

Four diagonal hops described by flip status, enemy landings and Coily distance.

Doodle Jump

platform choice

On each bounce the reachable platforms with height gain, offset and type.

Bubble Shooter

shot choice

Seven angles traced with wall bounces to what they pop and drop.

Match-3

swap choice

Valid swaps simulated one step: gems cleared, longest line, cascade.

Artillery Duel

shot choice · wind

Six angles with the power that lands nearest, and where each falls relative to the enemy.

Slalom

timing · latency-aware

Five leans simulated through the measured decision delay: where the skier crosses the next gate and where that leaves the one after.

Football 3v3

team roles · 2 personas

Carrier: pass, shoot, dribble. Others: support, press, mark, cover. Six questions per tick.

Sheep Herding

flocking

Push a cluster, collect a stray, or hold back while the flock settles.

Tower Defense

placement · economy

Best empty cells by path coverage and uncovered stretch, or save the gold. Waves, shooting and gold run in code.

Sumo

duel · momentum

Charge, sidestep, brace or retreat; each simulated past the decision delay against the opponent's current move.

Digger

boulders

Directions described by content, boulders that would fall, and distance to the nearest diamond.

Poker

hidden information · 6-max NLHE · not on the wall

Full cash game with side pots. Each seat sees its own view: hand description, raw equity, pot odds and the action so far.

Lunar Lander

physics · real-time

Jev picks a descent profile (drop, descend, hover) and a sideways intent three times a second; the code flies the thrust controller and reports the stopping margin.

Pac-Man

maze · real-time

At every junction each way out is described: pellets, nearest pellet, ghost ahead and whether it is frightened. Ghosts run classic chase logic in code.

Breakout

physics · quasi real-time

Interception is exact; Jev chooses which part of the paddle to hit with, from a traced prediction of what each return would hit.

Asteroids

shooter · real-time

The three nearest rocks with size, distance, turn needed and collision course, plus evade. Code aims and flies; Jev sets the priority.

Frogger

timing · quasi real-time

For each hop and for waiting, how long that square stays clear after landing, with the reaction delay already subtracted. Jev decides about three times a second.

Whack-a-Mole

targeting · latency-aware

Each mole: value, time left up, hammer travel time including the decision delay. Reachable or too late.

Penalties

probabilistic · commit timing

Three cues of stated reliability during the run-up; dive, stay, or wait for a better cue while there is time.

Fruit Slice

moving targets

Rising or falling, off-screen time, intercept time. Code flies the blade to the intercept point.

Lifeguard

triage

Time left, distance out, reach time on sand and water, tow time. Code runs, swims and tows.

Firefighter

triage · spreading

Which fire first: houses next to it, burning neighbours, truck arrival. Fire spreads on its own.

Bullet Dodge

positioning

Seven spots with time-to-hit and whether the path is crossed on the way. Code moves in a straight line.

Runner

plan · code-timed

Short jump, long jump, stomp or run for the next obstacle, each with its simulated landing. Code takes off at the right pixel.

Treasure Diver

budget · risk

Value against the oxygen for the round trip, sharks on some depths. Decisions on arrival, so it asks rarely.

Highway

gaps · closing speeds

Lane choice from the cars ahead and behind and whether the gap survives the delay plus the change.

How the wall works

What we learned building it

Under the hood