Project / Other

A backtested strategy runner. Different stack — built as an experiment.

Live demo
localhost:7890
Run · walk-forwardsynthetic series
Strategy
Range

long when SMA(6) crosses above SMA(18); flat when it crosses back

Equity, indexed to 100 at the start of the window
bar 126 / 126 SMA6 148.81 · SMA18 147.47
Trades
2
Win rate
100%
Net
+16.3%
Max drawdown
-5.6%

Synthetic price series, generated for this page — not a real instrument and not a track record. Long only, one position at a time, 8bp a side. Nothing here places an order. Different stack from the rest of this work; built as an experiment.

localhost:7890
Backtest replay — bundled historical data, executes nothing.
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What it is

Different stack from the rest of this page, and listed here as an experiment rather than as a service line.

A Python service that runs a small set of rule-based strategies against historical candles, records every entry and exit, and reports the result honestly — including the runs that lose. FastAPI in front, PostgreSQL underneath, an exchange API for the data feed.

The demo is a backtest replay: pick a strategy and a date range and watch the candles play back with the entries, exits, and running P&L drawn in as they happen. It executes nothing and it is not advice. It is here because the mechanism is interesting, not because it is a product.

How it works

History first, rules bar by bar, and the losing runs stay in.

  1. History comes first

    A Python service pulls historical candles from an exchange API, resamples them to the timeframe under test, and stores them in PostgreSQL. The backtest only ever sees data it would have had at the time — no look-ahead.

  2. Rules, evaluated bar by bar

    Indicators are computed with pandas / TA-Lib. A small set of rule-based strategies is walked forward one bar at a time, and every entry and exit is written down with its price and reason.

  3. The report includes the losses

    Output is P&L, win rate, and drawdown across the whole run — including the strategies and periods that lose money. FastAPI serves the result. Nothing places an order, and none of it is advice.

  • “It cleared the queue we could never keep up with. We only look at the handful it flags now.”

    Operations lead · multi-store retail operator

  • “Condition grading and pricing that used to be a weekend is now a photo upload.”

    Founder · collectibles brand

  • “The drafts are good enough that answering is now approving.”

    Operations lead · B2B services

  • “I stopped waiting for yesterday's numbers. Today's are just there, all stores in one view.”

    Owner · multi-store retail operator

  • “It books and qualifies before we're even awake. The morning list is just the ones worth a callback.”

    Founder · home-services company

  • “It shipped in pieces we could check as they landed, and the pieces we argued with got changed.”

    Operations manager · logistics

  • “None of it is rented. I did not expect that to matter as much as it turned out to.”

    Founder · consumer goods

Proof

Walkthrough
A backtest run start to finish — history loaded, the strategy walked forward bar by bar, and the report including the losing stretch.

The operation

Founder-led. Specialist-built.