MT4 and MT5 systems
Translate strategy rules into Expert Advisors and utilities.
- Entry and exit logic
- Stop-loss and take-profit management
- Position sizing
- Session and spread filters
What a custom MT5 EA project should define before coding
A reliable Expert Advisor starts with explicit rules. The specification should state the exact entry condition, invalidation condition, stop-loss and take-profit logic, position-sizing method, session filters, maximum simultaneous trades and what happens when data or execution is unavailable. Terms such as “strong trend” or “good momentum” need measurable definitions so the same market state produces the same decision in testing and production.
Typical deliverables
- MQL5 or MQL4 source code and compiled build where applicable.
- Configurable inputs for strategy and risk parameters.
- Broker-safe lot normalization and symbol-property handling.
- Execution, error and trade-management logs.
- Backtest/validation setup instructions and handover notes.
Trading bot requirements checklist
| Area | Questions to answer |
|---|---|
| Entries | Which timeframe, indicators, structure rules or price events create a valid setup? |
| Risk | Fixed lot, percentage risk, maximum portfolio exposure, daily loss cap? |
| Stops & targets | Fixed, structural, ATR-based, multi-target, break-even or trailing? |
| Execution | Market/pending orders, spread limit, slippage behavior, retry rules? |
| Sessions | Which trading hours, weekdays or market events should be blocked? |
| Validation | What data, date range, metrics and acceptance criteria define a successful build? |
Backtesting and forward validation
Strategy Tester results are useful only when the assumptions resemble the intended broker and market. Tests should include realistic spread and execution costs, then be checked on data that was not used to tune the rules. For parameterized systems, walk-forward or out-of-sample testing can reveal whether performance depends on one narrow historical period.
Win rate alone is not enough. A validation report should also inspect maximum drawdown, profit factor, expectancy, average win/loss, exposure, trade count and sensitivity to spread or slippage. Development can implement and test a strategy, but future returns cannot be guaranteed.
When a bridge or API is needed
Not every system should live entirely inside MT5. TradingView signals, Telegram messages, external machine-learning services or portfolio logic can require an API bridge. In those cases, the design should include authentication, durable event IDs, deduplication, retry behavior and reconciliation with the actual broker state.