Discussing the article: "Keeping Memory Across Restarts: EA State Persistence Using Binary Files in MQL5"

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Check out the new article: Keeping Memory Across Restarts: EA State Persistence Using Binary Files in MQL5.

This article provides a structured MQL5 framework for serializing an Expert Advisor's internal state into local binary files. It prevents data resets during platform restarts by safely storing volatile tracking metrics, such as trade counts and multipliers, directly to disk. This architecture offers a more robust state continuity alternative to terminal Global Variables.

Maintaining state continuity across terminal restarts is critical for Expert Advisors that track multi-trade metrics. Examples include daily frequency caps and position-sizing progressions. Because standard MQL5 variables reside strictly in volatile memory, routine terminal restarts reset the EA's internal counters to their default values. This introduces execution vulnerabilities where an EA may bypass its risk parameters or miscalculate lot sizes upon initialization. The standard workaround of utilizing terminal Global Variables is structurally inadequate for complex logic. These variables are limited to storing individual double values, lack data structure hierarchy, and are easily erased during terminal reinstallation or directory maintenance.

This article presents a framework for state serialization using native MQL5 binary file operations. It stores the EA's runtime state in a single struct, writes it on key events, and reloads it on initialization. The resulting include file, PersistenceManager.mqh, provides a self-contained, low-overhead mechanism that ensures an EA preserves its operational state across restarts, platform updates, and profile changes without relying on external databases or fragile terminal configurations.

Author: Ushana Kevin Iorkumbul