Your backtest is probably lying to you. Here is the cheapest way to find out.

Run it again with 0.05% slippage per side and funding costs included.

Most strategies that look profitable are running on a 0.1 to 0.3% edge per trade. Costs that size eat the edge completely.

If your equity curve survives that, you have a strategy. If it does not, you had a spreadsheet.

What is the first thing you add to a backtest before you trust it?

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