Paper, Backtest, and Live Differences

Backtest, paper, and live disagreeing is usually environment difference, not a fault. Compare against the tables before reporting.

Backtest vs paper

Difference	Why
Market window	Backtests replay the past; paper trades the present
Fill model	Backtests fill idealistically; paper matches live books
Duration	Months of backtest vs days of paper isn’t comparable
Version	Confirm paper runs the exact backtested parameters

Verdict: run paper for weeks across varied markets before comparing.

Difference	Why
Slippage and depth	Live eats the real book; grows with size
Fees	Live pays your actual tier rates
Funding	Live positions actually pay/receive funding

Narrow the gap: match paper balance to live size; go live small for a week or two; scale carefully on thin symbols.

Report with both strategy names, the timestamp, and event-history entries if:

Paper and live take opposite directions on the same signal at the same time;
An order shows filled in events but the exchange shows no position change;
Same parameters but different config revisions on the two detail pages.

When you are ready to scale from paper to live, follow From Paper to Live.