A backtest is a model of past behavior. A live trading bot is a stateful system interacting with changing data, network connections, broker rules, and asynchronous order events. AI-generated code often implements the visible entry rule while leaving those operating conditions implicit.
Historical data is cleaner than live data
Historical bars arrive complete. Live bars develop tick by tick, can be revised by the data feed, and may be interrupted. A bot that reads the current bar, higher-timeframe values, or reconstructed order flow can make decisions with information that was not available at the simulated decision time.
Simulated fills are assumptions
Backtests approximate queue position, spread, slippage, partial fills, rejected orders, and liquidity. A limit order that fills perfectly in a bar-based simulation may remain unfilled live. Stops can gap, market orders can slip, and a broker can reject prices or quantities.
Live systems have failure states
Connections drop. Platforms restart. Orders remain working. Strategy state can disagree with the account. Duplicate alerts arrive. External services retry requests. A production design needs explicit recovery, reconciliation, idempotency, monitoring, and manual controls.
Optimization can hide fragility
AI makes it easy to generate variations and optimize parameters. Repeated selection against the same history can produce a convincing result that does not generalize. Separate research, validation, and out-of-sample evidence, and document every assumption.
Move toward live use gradually
Reproduce signals, use playback where available, test simulation and demo environments, inspect logs, introduce realistic costs, verify reconnect behavior, and define a controlled rollout with small exposure and a rollback plan.
Use the Production-Readiness Review when a system is complete or nearly complete. If the code itself is still questionable, start with the AI-Built Trading System Audit.
Risk note
Technical review cannot guarantee fills, uptime, safety, profitability, or live results. This article is software guidance, not trading or investment advice.