MQL5 Programming Articles

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Study the MQL5 language for programming trading strategies in numerous published articles mostly written by you - the community members. The articles are grouped into categories to help you quicker find answers to any questions related to programming: Integration, Tester, Trading Strategies, etc.

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Markov Chains in Trading and Price Forecasting

Markov Chains in Trading and Price Forecasting

In this article, we will examine how to build and apply Markov chains in market conditions: from selecting states and counting transitions to generating forecasts of trajectories and levels. We will also see how Markov chains can be applied to qualitative and quantitative data, ways to account for rare events, and the impact of the forecast horizon. Examples are provided using prices and indicators, as well as an option for evaluating a sequence of trades, with ready-to-use implementations in MQL5.
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Motifs and Discords: Building a Matrix Profile from Scratch

Motifs and Discords: Building a Matrix Profile from Scratch

We build the Matrix Profile for MQL5 from the ground up and keep it numerically stable on real prices. The library includes rolling statistics, a radix-2 FFT powering MASS, and a STOMP self-join, with results matched to stumpy. A compact facade, an indicator that draws the profile and flags discords, and a demonstration Expert Advisor show how to read and use the signal in practice.
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Graph Theory: Study of Graphs Generated by Some Random Process

Graph Theory: Study of Graphs Generated by Some Random Process

This article describes an MQL5 Expert Advisor that models the market as a random graph rather than a fixed structure. Bars are encoded into discrete states; bar-to-bar moves form a decaying, Laplace-smoothed transition matrix, and a k-step random walk yields a bounded directional signal gated by an Erdos–Renyi null-model test. A separate trade-outcome graph over R-milestones learns survival probabilities to manage exits, turning position management into evidence-based rules.
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From Basic to Intermediate: Object Events (III)

From Basic to Intermediate: Object Events (III)

In this article, we will prepare the foundation for what will be covered in the next publication. We will also look at how to make an OBJ_LABEL object fully interactive for editing and moving. In other words, we can change both the text and the position of the OBJ_LABEL object without opening the Object Properties dialog.
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Beyond GARCH (Part VI): Fractional Brownian Motion And The Multiplicative Cascade in MQL5

Beyond GARCH (Part VI): Fractional Brownian Motion And The Multiplicative Cascade in MQL5

This article implements the MMAR Simulation Engine that turns fitted parameters (H, distribution, coefficients, sample volatility) into synthetic price paths. It builds multifractal trading time via a multiplicative cascade, synthesizes fractional Brownian motion with Davies–Harte or Cholesky, scales it to target volatility, and composes the process by time deformation. Readers get a reusable MQL5 class, method choices by path length, and validation steps for scenario testing and Monte Carlo use in the next part.
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From Basic to Intermediate: Classes (II)

From Basic to Intermediate: Classes (II)

This article is intended to be as educational as possible, since the topic we will be discussing often causes considerable confusion in itself. Therefore, dear reader, please try to put what is explained here into practice. If you have any questions, be sure to leave a comment—after all, understanding destructors is no easy task.
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Defining your Edge (Part 3): Using HMM and GRU in an Expert Advisor

Defining your Edge (Part 3): Using HMM and GRU in an Expert Advisor

We examine how a Hidden Markov Model (HMM) estimates latent market regimes while basing on observable price and indicator sequences. This is done by estimating the probability of state transitions. A Gated Recurrent Unit (GRU) network models time dependencies and keeps important information over several observations. In an Expert Advisor, HMM-based regime probabilities, can be merged with GRU-based sequence learning to better classify increments in accumulation, distribution, and momentum prior to their showing up in regular price confirmations.
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MetaTrader 5 as a Kafka Producer: Event-Bus Architecture for Multi-Terminal Signal Fan-Out

MetaTrader 5 as a Kafka Producer: Event-Bus Architecture for Multi-Terminal Signal Fan-Out

The article details a native MQL5 Kafka producer that speaks the wire protocol over raw TCP. It implements RecordBatch v2 encoding, varints, and CRC32C, and adds batching, acks, and retry logic, all without a sidecar or DLL. Use it to publish JSON-structured trading signals from a single terminal to Kafka, where dashboards and other services subscribe independently.
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Building a Prop-Firm Compliance Monitor in MQL5 (Part 1): Account Rules and Persistent Settings

Building a Prop-Firm Compliance Monitor in MQL5 (Part 1): Account Rules and Persistent Settings

Establishes the persistence foundation for a prop-firm compliance EA in MetaTrader 5. It introduces rule inputs and status enums, separates live account state from stored settings, validates percentages and thresholds, and implements SQLite open/close, schema creation, and prepared save/load operations. Using the account login and server as a composite key, the EA restores existing settings and updates them when inputs change.
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Neural Networks in Trading: Generalizing Time Series Without Data-Specific Dependence (Core Model Modules)

Neural Networks in Trading: Generalizing Time Series Without Data-Specific Dependence (Core Model Modules)

We continue our acquaintance with the Mamba4Cast framework. Today, we will delve into the practical implementation of the proposed approaches. Mamba4Cast was designed not for lengthy warm-up on every new time series, but for immediate deployment. Thanks to the concept of Zero-Shot Forecasting, the model can produce high-quality forecasts on real-world data without additional training or hyperparameter tuning.
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From Basic to Intermediate: Object Events (IV)

From Basic to Intermediate: Object Events (IV)

In this article, we will complete what was started in the previous one: a fully interactive way to resize objects directly on the chart. Although many people imagine that creating something like this would require much deeper knowledge of MQL5, you will see that, using simple concepts and basic knowledge, we can implement a way to work with objects directly on the chart. This leads to a very interesting and quite compelling result.
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Master MQL5 — From Beginner to Pro (Part VII): Principles of Debugging MQL Applications

Master MQL5 — From Beginner to Pro (Part VII): Principles of Debugging MQL Applications

Debugging is an integral part of the programming cycle. This article discusses common techniques for debugging any application running in the MetaTrader 5 environment.
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How to Set Up an AI Hedge Fund in MetaTrader 5

How to Set Up an AI Hedge Fund in MetaTrader 5

The article examines the architecture of a committee consisting of 15 AI agents: ten analysts and four risk officers vote in three parallel phases, and the Chair records the final result. Isolated pair contexts with separate reputations are used for eight currency pairs. The dynamic vote threshold depends on the daily PnL targets. The Expert Advisor uses only the signal, SL and TP, which allows for evaluation pf the quality of its decisions without any additional mechanics.
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Rolling Sharpe Ratio with Statistical Significance Bands in MQL5

Rolling Sharpe Ratio with Statistical Significance Bands in MQL5

This article presents a custom MetaTrader 5 indicator that computes a rolling annualized Sharpe ratio and plots configurable z-score significance bands based on Lo's asymptotic standard error. It uses a circular return buffer with incremental variance to keep O(1) updates. We explain the n^(-1/2) uncertainty scaling, the inflation of intervals at high Sharpe values, and how to set per-instrument annualization for correct deployment.
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Trade Entry Timing Accuracy Analyzer in MQL5

Trade Entry Timing Accuracy Analyzer in MQL5

This article builds an MQL5 dashboard that evaluates entry timing for closed positions using tick‑based Maximum Adverse Excursion (MAE) and Maximum Favorable Excursion (MFE). It computes an entry efficiency ratio, renders an MAE/MFE scatter plot and an efficiency histogram, and prints a concise summary to the Experts tab. Deal grouping, tick‑level excursion logic, and a standalone verification script are included so you can diagnose entry quality across many trades.
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Price Action Analysis Toolkit Development (Part 83): Building a Reusable Double-Bottom Pattern Library

Price Action Analysis Toolkit Development (Part 83): Building a Reusable Double-Bottom Pattern Library

This recorder bridges visual labeling and systematic research in MQL5. After you position a rectangle, the EA extracts the candles it spans, derives candle geometry, normalizes OHLC values, assigns an ID, and saves the sample for reuse across sessions. The current category is the double bottom, and the module records the chosen sequence without enforcing a predefined pattern definition.
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Market Simulation: Position View (VII)

Market Simulation: Position View (VII)

In this article, we'll start making some improvements to the position indicator so that we can interact with it and modify price lines or close a position directly through the position indicator. Before we move on to the implementation, there are a few things worth clarifying, especially for those who aren't familiar with this. The indicator cannot be used in any way to change anything on the trading server. This is because MetaTrader 5 has a security system in place that allows only Expert Advisors to modify orders and positions. No application other than an Expert Advisor can manipulate orders or positions.
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Exporting Symbol Tick Data to Binary Files in MQL5 for Offline Analysis

Exporting Symbol Tick Data to Binary Files in MQL5 for Offline Analysis

The article delivers a complete, verifiable tick export path from MQL5 to a binary file and into Python. It defines a 64‑byte header, 48‑byte records with millisecond time and flags, an export pipeline using CopyTicksRange(), and a single‑call NumPy loader. Users obtain compact, precision‑preserving files and a reproducible workflow for vectorized analysis.
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Market Simulation: Position View (VIII)

Market Simulation: Position View (VIII)

In the previous article, we considered how to implement a position indicator that allows you to close an open position directly from the chart by interacting with an object available on the chart. After completing and testing the first mechanism, we began making changes to ensure that take-profit and stop-loss levels could be removed for an open position. However, since the necessary changes required detailed explanations, in that same article I showed only the changes that needed to be made to the expert advisor; I still needed to show the changes that needed to be made to the position indicator.
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Neural Networks in Trading: Adaptive Periodic Segmentation (Conclusion)

Neural Networks in Trading: Adaptive Periodic Segmentation (Conclusion)

We invite you to dive into the exciting world of LightGTS — a lightweight yet powerful framework for time-series forecasting, where adaptive convolution and RoPE encoding are combined with innovative attention mechanisms. In our article, you will find a detailed description of all components — from creating patches to the complex mixture of experts in the decoder — ready for integration into MQL5 projects. Discover how LightGTS takes automated trading to a whole new level!
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From Basic to Intermediate: Object Events (II)

From Basic to Intermediate: Object Events (II)

In this article, we will look at how the last three types of events generated by an object work. Understanding this will be very interesting, because in the end we will do something that may seem crazy to many people, but it is entirely possible and produces a very surprising result.
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How to Obtain Synchronized Arrays for Use in Portfolio Trading Algorithms

How to Obtain Synchronized Arrays for Use in Portfolio Trading Algorithms

The article describes a practical approach to synchronizing bars between instruments in a portfolio in MQL5. Classes are provided for loading, storing, and aligning OHLCV data, with options to use an empty bar or carry over values from the previous bar, select a synchronization symbol, and process new bars asynchronously. Examples of use in multi-chart and basket indicators are shown. Readers receive a ready-to-use API for reliable portfolio calculations.
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Deterministic Dendritic Cell Algorithm (dDCA)

Deterministic Dendritic Cell Algorithm (dDCA)

The article presents an adaptation of the Deterministic Dendritic Cell Algorithm (dDCA) for continuous optimization problems. The algorithm, inspired by the immune system's Danger Theory, uses a signal accumulation mechanism to automatically balance exploration and exploitation within the search space.
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Real-Time Trade Event Logger to SQLite via MQL5 DLL Bridge

Real-Time Trade Event Logger to SQLite via MQL5 DLL Bridge

The article shows how to build an MQL5 EA that writes every deal to an SQLite database the moment it appears, using the built-in Database API as the SQLite bridge. It implements an event data model, a prepared INSERT workflow reused across calls, session-safe recovery after restarts, and deal detection via OnTrade(). You can open the resulting file with any SQLite client to run queries for analysis and reporting.
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Neural Networks in Trading: The Adaptive Graph Diffusion Model (Attention Module)

Neural Networks in Trading: The Adaptive Graph Diffusion Model (Attention Module)

In this article, we will take a detailed look at the practical implementation of the key components of the SAGDFN framework. We will show how sparse attention and the selection of significant neighbors are organized for time series forecasting. The approaches presented strike a balance between forecast accuracy and computational efficiency.
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Building a Type-Safe Event Bus in MQL5: Decoupling EA Components Without Global Variables

Building a Type-Safe Event Bus in MQL5: Decoupling EA Components Without Global Variables

A typed publish-subscribe event bus in MQL5 replaces global variables and direct cross-references. Using an abstract listener interface and an enum-indexed subscription table, a signal engine, order manager, and drawdown monitor communicate only through the bus, with no shared state. The article analyzes dispatch overhead, pointer validation, and recursive publish risks, helping you design decoupled, testable EAs.
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A Reusable Breakeven Manager in MQL5 with Spread Compensation

A Reusable Breakeven Manager in MQL5 with Spread Compensation

A robust breakeven implementation for MQL5 is built around live spread sampling and correct pip-to-price conversion by symbol digits. CBreakevenManager moves SL to open_price ± spread ± buffer once a real‑pip activation threshold is reached and prevents duplicate modifications. A demo EA shows the behavioral difference versus a naive breakeven, and a script verifies core calculations.
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CSV Data Analysis (Part 6): Multi-Broker Result Normalization and Cross-Platform CSV Reconciliation

CSV Data Analysis (Part 6): Multi-Broker Result Normalization and Cross-Platform CSV Reconciliation

This article presents a multi‑broker CSV normalization framework. An MQL5 include file enriches exports with broker metadata. A Python module resolves schema divergences — pip conventions, symbol aliases, time offsets, commission models, and currency denomination — producing a unified canonical dataset. Comparative visualizations of slippage distributions and net‑of‑cost performance enable reliable cross‑platform strategy analysis without silent data corruption.
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MQL5 Wizard Techniques you should know (Part 94): Using Reservoir Sampling and Linear Regression in a Custom Trailing Stop Class

MQL5 Wizard Techniques you should know (Part 94): Using Reservoir Sampling and Linear Regression in a Custom Trailing Stop Class

For this article we rotate to a custom MQL5 Wizard class implementation that explores Trailing Stops. Our custom class is ‘CTrailingReservoirLinReg’ that we derive by combining the Reservoir Sampling algorithm with a Linear Regression network. As has been the case throughout these series, this formulation is testable with MQL5 Wizard Assembled Expert Advisors that can be tuned with various entry signals and money management classes.
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How to Create and Adapt an RL Agent with an LLM and Quantum Encoding for Algorithmic Trading in MQL5

How to Create and Adapt an RL Agent with an LLM and Quantum Encoding for Algorithmic Trading in MQL5

The article proposes a hybrid approach to algorithmic trading based on quantum encoding of market states, Double DQN with a prioritized experience replay buffer, and an LLM acting as a contextual EA. The SEAL methodology enables asynchronous continued training of the agent without halting trading. A lightweight Q-learning filter (USE/SKIP/REDUCE) controls signal execution at the meta-level. Practical details are provided on integrating the system with the MetaTrader 5 trading platform, along with a scheme for adapting it to market regime shifts.
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Implementing and Benchmarking Bag-of-SFA-Symbols (BOSS) Against Dynamic Time Warping (DTW)

Implementing and Benchmarking Bag-of-SFA-Symbols (BOSS) Against Dynamic Time Warping (DTW)

This article implements BOSS from scratch in MQL5 and applies it to regime classification: SFA turns windows into words, bags record word frequencies, and an ensemble over window lengths votes on labels. We cover the encoding steps, the BOSS distance, training with auto-generated regime labels, and practical parameters. A BTCUSD benchmark versus DTW shows higher macro accuracy on clean data and markedly faster inference.
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Honest Backtesting of Swing Strategies on Index CFDs: Financing Costs, Swap Modes, and What the Strategy Tester Cannot Model

Honest Backtesting of Swing Strategies on Index CFDs: Financing Costs, Swap Modes, and What the Strategy Tester Cannot Model

Financing drives multi‑day index‑CFD results: in one full‑history test, swap consumed 44% of gross profit and all profit on one symbol. We convert swaps to annualized rates, contrast four brokers and two financing models with a read‑only script, and quantify a Strategy Tester issue where a single current swap is used for all history, inflating implied rates by up to seven times. The piece provides a repeatable cost‑audit method.
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Creating a Cairo-Inspired Graphics Library for MetaTrader 5 (Part 1): Why the terminal needs its own 2D-renderer Contents

Creating a Cairo-Inspired Graphics Library for MetaTrader 5 (Part 1): Why the terminal needs its own 2D-renderer Contents

This article opens a step-by-step 2D graphics engine for MetaTrader. It standardizes ARGB colors and implements a reusable surface: a uint pixel buffer uploaded as a dynamic resource and shown via one OBJ_BITMAP_LABEL. You will draw rectangles and a vertical gradient, check real transparency, and learn an efficient update path with a single Flush call.
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From Basic to Intermediate: Object Events (I)

From Basic to Intermediate: Object Events (I)

In this article, we will look at three of the six events that MetaTrader 5 can generate when some change occurs to an object on the chart. These events are very useful from the standpoint of user interaction. This is because, without understanding these events, we would have to put in much more effort to maintain a specific chart configuration when trying to manage objects for particular purposes.
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Architecture for Collective Trading Decisions by AI Agents

Architecture for Collective Trading Decisions by AI Agents

The article describes the architecture of a multi-agent trading system based on the grok-4-fast language model, in which, instead of a single system prompt, four independent analysts with fundamentally different roles operate: a bull, a bear, a risk manager, and an arbiter. Three analysts run in parallel using a ThreadPoolExecutor and, within 3–5 seconds, formulate well-reasoned positions based on the same market data; after that, a deterministic judge renders a final verdict according to strict rules.
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Neural Networks in Trading: A Unified View of Space and Time (Conclusion)

Neural Networks in Trading: A Unified View of Space and Time (Conclusion)

The Extralonger framework demonstrates a unique ability to integrate spatial and temporal factors into a single model, ensuring high forecast accuracy. Its architecture allows it to adapt to different planning horizons and financial instruments while maintaining the system's transparency and manageability.
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How to Use Finite Differences for Price Forecasting

How to Use Finite Differences for Price Forecasting

The article examines the practical application of finite differences in trading: types of differences, their relationship to price dynamics, and the binomial transform for noise filtering. The rules for encoding patterns based on difference levels and the application of these patterns to forecasting are described. This section presents naive, adaptive, and probabilistic approaches that help smooth time series, identify recurring patterns, and estimate future movements.
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Building AI-Powered Trading Systems in MQL5 (Part 12): Giving the Assistant Chart Vision and Tool Access

Building AI-Powered Trading Systems in MQL5 (Part 12): Giving the Assistant Chart Vision and Tool Access

We give our AI chat assistant two new abilities in MQL5: sight and tool access. It can now capture the chart as a screenshot, attach it to a message, and view it in the panel, and it can call tools that read live positions, trade history, indicator values, chart objects, and the economic calendar. The assistant reasons from what it sees and queries rather than text alone.
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Neural Networks in Trading: A Cross-Domain Time Series Forecasting Framework (Conclusion)

Neural Networks in Trading: A Cross-Domain Time Series Forecasting Framework (Conclusion)

The article focuses on the practical implementation of the TimeFound model for time series forecasting. The key stages of implementing the framework's main approaches using MQL5 are examined.
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Beyond GARCH (Part VII): Monte Carlo Volatility Forecasting in MQL5

Beyond GARCH (Part VII): Monte Carlo Volatility Forecasting in MQL5

We implement the CMonteCarlo module that turns the fitted MMAR parameters into a volatility forecast via Monte Carlo. It runs N independent simulations over a chosen horizon and reports mean, median, standard deviation, and a percentile-based 95% confidence interval, with access to per-run values if needed. Adaptive cascade depth selects the minimal k such that b^k covers the horizon, keeping the run fast and consistent.