Codeseum
    ◆WR · Sieve of Aurelius · 3:21 · vex.io◆Podium · Forum.cs refactor · od_in◆New trial · K-shortest paths · halfstep◆Findings · Pratt parser · 8.4 / 10◆Live · Contract NER · saltwater◆Medal · k0rax · Silver → Gold◆WR · Race window · 2:11 · k0rax◆New Judge · n.publicola · Builder◆Duel · vex.io def. od_in · +18 Elo◆Codesport · queue open · Algo◆WR · Sieve of Aurelius · 3:21 · vex.io◆Podium · Forum.cs refactor · od_in◆New trial · K-shortest paths · halfstep◆Findings · Pratt parser · 8.4 / 10◆Live · Contract NER · saltwater◆Medal · k0rax · Silver → Gold◆WR · Race window · 2:11 · k0rax◆New Judge · n.publicola · Builder◆Duel · vex.io def. od_in · +18 Elo◆Codesport · queue open · Algo
    Anno · MMXXVI·home of Codesport

    Prove you're better thanthe field.your idol.your last self.the field.

    The ranked league for AI-assisted coding. Real problems, a real clock, your engine of choice. Run it solo, or take a Codesport duel. Three scores, one leaderboard, free to enter.

    Enter the arena →How it works
    412
    Trials live
    1,287
    Attempts today
    37
    World records
    The arena · right nowrefreshing 1s
    In the arena
    6 active·1,287 today
    Competitor
    Trial
    Discipline
    T
    Mark
    • vex.ioDE
      Sieve of Aurelius
      ALGO · Opus 4.6
      6:52
      78
    • k0raxJP
      Race window in mutex
      DEBUG · GPT-5
      3:53
      submit91
    • od_inNO
      Contract NER
      PROMPT · Gem 2.5
      3:08
      83
    • minimal_lyraBR
      Forum.cs, 2.4k LOC
      REFACTOR · Opus 4.6
      19:40
      64
    • saltwaterUS
      Pratt parser, JSON-ish
      CRAFT · GPT-5
      12:45
      findings71
    • halfstepGB
      K-shortest paths
      ALGO · Llama 405
      15:21
      56
    Engines · self-declaredyoutube.com/@codeseum
    Claude Opus 4.6GPT-5Gemini 2.5 ProLlama 3.3 405BMistral MagnumDeepSeek V3Qwen 3 MaxGrok 4Claude Opus 4.6GPT-5Gemini 2.5 ProLlama 3.3 405BMistral MagnumDeepSeek V3Qwen 3 MaxGrok 4Claude Opus 4.6GPT-5Gemini 2.5 ProLlama 3.3 405BMistral MagnumDeepSeek V3Qwen 3 MaxGrok 4

    How it works. In four moves.

    ~ 90 seconds in
    I01 / 04

    Pick a trial

    Five domains. You choose.

    II02 / 04

    Wire your engine

    Bring your own key. We never see it.

    III03 / 04

    Run the clock

    Editor + chat + recorder. Go.

    IV04 / 04

    Get rated

    MARK · ROOM · FINDINGS. Then again.

    Five domains. You choose.

    Medals stack per discipline. No one is good at all five.

    I

    ALGO

    Algo

    WR
    3:21
    Trials
    142
    Enter →
    II

    CRAFT

    Craft

    WR
    12:48
    Trials
    76
    Enter →
    III

    DEBUG

    Debug

    WR
    2:11
    Trials
    98
    Enter →
    IV

    REFACTOR

    Refactor

    WR
    19:33
    Trials
    54
    Enter →
    V

    PROMPT

    Prompt

    WR
    1:48
    Trials
    42
    Enter →

    One number lies. Three tell the truth.

    the math

    MARK

    range · 0–100

    the peers

    ROOM

    range · 1–9

    the judge

    FINDINGS

    range · 1–10

    COMPETITION BRINGS OUT THE BEST · COMPETITION BRINGS OUT THE BEST · COMPETITION BRINGS OUT THE BEST · 

    Why we built this

    “Competition brings out the best of the best.”

    Medals you earn, not buy.

    The mark you carry is the mark you earned. Diamond is reserved for world records — one trial, one holder.

    III

    Bronze

    Top 15%

    Past the entry mark. In the ranked.

    II

    Silver

    Top 5%

    Consistent, dangerous, climbing.

    I

    Gold

    Top 1%

    Reserved for the rare air.

    WR

    Diamond

    World record

    One per trial. Held until it’s broken.

    Part one

    You bring the keys.

    • Any engine. Any provider.
    • Free to enter. Always.
    • Your code. Your IP. Your call.

    Part two

    Every attempt is on tape.

    Recorded, signed, replayable. The broadcast is our anti-cheat — if it didn't happen on camera, it didn't happen.

    Watch on YouTube →Receipts in public

    The clock's on. Find out where you stand.

    Enter the arena →See the standings