Replay · Backtest · Prop challengesThe longest night of the year

Backtests that
keep their word.The longest night,
then light.

Replay any market candle by candle, blind to the future, and walk away with numbers that never peeked.Tonight the sun is reborn. Replay the whole year candle by candle, and meet the dawn with a strategy you have already tested.

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  • 0Bars of look-ahead
  • 100%Deterministic replays
  • 84Drawing tools

REPLAY · D1 · ONE YEAR

100% client-side backtesting: your candle and tick data is processed in your browser, never uploaded. Replay at your dataset's resolution, trade the MT5-style terminal, automate strategies, and replay multi-symbol portfolios in one shared account.

What it is

  • Local-first backtesting

    Datasets live in your browser's storage. Backtests execute in workers on your machine.

  • Replay with order realism

    Step through candles, place market/limit/stop orders with SL/TP, watch the journal fill in.

  • Automated strategies

    Build block-based strategies visually; backtest them headlessly; sweep parameters with the optimizer.

  • Multi-symbol portfolios

    Trade up to four of EURUSD, GBPUSD, USDJPY, EURGBP, gold and silver manually in ONE account with shared risk; non-USD profits are converted to USD. Runs on data you import.

  • Bring your own data

    Import CSV/tick files or connect a permitted cloud source. No dataset redistribution promises — your data stays yours.

What it is NOT

  • Not investment advice. Not a broker. Not live trading. Backtests are simulations of past data.
  • No guaranteed profits, no signals, no predictions.

Tech & trust

  • Backtesting executes locally in your browser; candle/tick data remains on your device (imported datasets are never synced).
  • An account is required for any app use. New accounts get a free 4-day trial of Pro; after it, choose a plan to keep using the app. Nothing on your device is deleted when a plan ends.
  • Billing is crypto-only: you top up an account balance with USDT on TRC-20/BEP-20 (from $10) and buy a plan from it (Basic, Pro and Premium, from $9 / 30 days), no auto-renew. Top-ups are final and never refunded — use the trial first.
  • Light-data sync (tests/settings/strategies) happens only with your consent; account/billing/support records live on the server. Error reporting is configured, not covert.

Backtests that keep their word.The longest night, then light.

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