MQL4 and 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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Building a JSON Trade Report Exporter in Pure MQL5

Building a JSON Trade Report Exporter in Pure MQL5

A refined MQL5 script exports trade history to a well‑formed JSON file in MQL5/Files/, reconstructing trades from deals by position ID and recovering stop loss and take profit via a two‑pass lookup that falls back closed to the originating order. It includes a dedicated JSON serializer and computes R‑multiple, pip profit, and duration. The result loads cleanly in Python, R, or Excel without custom parsing.
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Custom Debugging and Profiling Tools for MQL5 Development (Part III): Regression Gates for Performance and Trading Rules

Custom Debugging and Profiling Tools for MQL5 Development (Part III): Regression Gates for Performance and Trading Rules

This article adds a regression gate to the MQL5 debugging and profiling workflow. It keeps the Part II profiler, TestLite runner, and trading math helper as contracts, then compares current profiler evidence with an accepted baseline. The workflow also adds symbol-aware assertions, compact status files, and report tables so performance drift, missing tests, and broker-assumption problems are visible before a build is accepted.
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Trust Your Backtest Data First: Building a Reproducible Historical Data Audit in Python for MetaTrader 5

Trust Your Backtest Data First: Building a Reproducible Historical Data Audit in Python for MetaTrader 5

A reproducible, read-only Python audit for MetaTrader 5 that verifies history quality before any backtest. It exports M5 data from multiple terminals, detects gaps and synthetic bars by timestamp spacing, and reports coverage per year. The same deterministic strategy then runs on three broker feeds over a common window to quantify result drift and decompose it into spread, data/price, and trade effects.
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Introduction to MQL5 (Part 34): Mastering API and WebRequest Function in MQL5 (VIII)

Introduction to MQL5 (Part 34): Mastering API and WebRequest Function in MQL5 (VIII)

In this article, you will learn how to create an interactive control panel in MetaTrader 5. We cover the basics of adding input fields, action buttons, and labels to display text. Using a project-based approach, you will see how to set up a panel where users can type messages and eventually display server responses from an API.
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Code, Tears, and Algo Forge

Code, Tears, and Algo Forge

This article discusses the transition to MQL5 Algo Forge as a modern and convenient format for publishing program code and article attachments. Using repositories instead of traditional ZIP archives and source code allows you to keep projects up-to-date, make edits quickly, and professionally interact with your readers. Recommendations are provided for quickly migrating developments to the cloud environment via the MetaEditor interface.
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Market Microstructure in MQL5 (Part 4): Volatility That Remembers

Market Microstructure in MQL5 (Part 4): Volatility That Remembers

This article adds eight volatility functions to MicroStructure_Foundation.mqh, including realized volatility, duration-adjusted volatility, fractional volatility, a FIGARCH-inspired proxy, a volatility clustering index, a GJR-GARCH asymmetry measure (using the Dube library), bipower-variation jump detection, and a wrapper function. The MFDFA implementation is revised to return the conventional Legendre-transform Δα with an R² confidence field, replacing the τ-spread proxy used in the original submission. Thresholds are derived from 514 NY sessions of NQ E-mini Nasdaq 100 futures (May 2024–May 2026); no new include file is created.
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Building an Object-Oriented Order Block Engine in MQL5

Building an Object-Oriented Order Block Engine in MQL5

The article presents a production-oriented Order Block engine for MQL5 packaged as an include class, it validates zones via displacement and market structure break, maintains mitigation state only on closed bars, and avoids heavy copies by passing data by reference. A diagnostic indicator plots zones, and an EA gates logic to new bars for stable performance and reproducible tests.
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MQL5 Trading Tools (Part 35): Adding Channel, Pitchfork, Gann, and Fibonacci Tools to the Canvas Drawing Layer

MQL5 Trading Tools (Part 35): Adding Channel, Pitchfork, Gann, and Fibonacci Tools to the Canvas Drawing Layer

We extend the canvas drawing layer from the previous part with seven new categories of multi-anchor analytical drawing tools, covering three channel variants, three pitchfork variants, three Gann tools, and the six Fibonacci tools. We work through how each tool encodes its geometry on the canvas, how derived handles let users reshape compound shapes coherently, and how shared helpers handle ray clipping, scanline filling, and anti-aliased arc rendering. By the end, we will have a full set of analytical drawing tools that live on the same interactive canvas alongside the basic line tools from the previous part.
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Broker Reality Check (Part 1): Why Your EA Works on a Demo and Breaks on a Client's Broker

Broker Reality Check (Part 1): Why Your EA Works on a Demo and Breaks on a Client's Broker

Your Expert Advisor runs clean on your demo, then throws errors on a client's broker and quietly stops trading - and the code never changed. What changed is the broker's rulebook. This first article of the Broker Reality Check series builds a diagnostic EA that reads every relevant symbol trading condition - filling policy, stops and freeze levels, volume step, trade mode, swap and the triple-swap day - and flags the ones that silently break EAs, in plain language. It shows a green/amber/red panel, prints a report and dumps every Market Watch symbol to CSV, so you see why an OrderSend fails (10030, invalid stops, invalid volume) before it costs you a trade.
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Position Management: A Reusable Trade Journal with Live Maximum Adverse Excursion, Maximum Favorable Excursion, and R-Multiple Tracking in MQL5

Position Management: A Reusable Trade Journal with Live Maximum Adverse Excursion, Maximum Favorable Excursion, and R-Multiple Tracking in MQL5

This article presents CTradeJournal, a self-contained MQL5 class for live tracking of open positions at tick frequency. It maintains MAE, MFE, and initial risk in money, calculates the R-multiple when a position closes, and writes a complete CSV record. The text explains the design choices, provides the implementation, and shows simple EA integration so you can analyze entries, stop placement, and outcome distribution.
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Developing a Replay System (Part 58): Returning to Work on the Service

Developing a Replay System (Part 58): Returning to Work on the Service

After a break in development and improvement of the service used for replay/simulator, we are resuming work on it. Now that we've abandoned the use of resources like terminal globals, we'll have to completely restructure some parts of it. Don't worry, this process will be explained in detail so that everyone can follow the development of our service.
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Market Simulation: (Part 11): Sockets (V)

Market Simulation: (Part 11): Sockets (V)

We are beginning to implement the connection between Excel and MetaTrader 5, but first we need to understand some key points. This way, you won't have to rack your brains trying to figure out why something works or doesn't. And before you frown at the prospect of integrating Python and Excel, let's see how we can (to some extent) control MetaTrader 5 through Excel using xlwings. What we demonstrate here will primarily focus on educational objectives. However, don't think that we can only do what will be covered here.
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From Basic to Intermediate: Indicator (III)

From Basic to Intermediate: Indicator (III)

In this article, we will explore how to declare various graphical representation indicators, such as DRAW_COLOR_LINE and DRAW_FILLING. Additionally, of course, we will learn how to plot graphs using multiple indicators in a simple, practical, and fast way. This can truly change your perspective on MetaTrader 5 and the market as a whole.
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Quantum Neural Network in MQL5 (Part I): Creating the Include File

Quantum Neural Network in MQL5 (Part I): Creating the Include File

The article presents a new approach to creating trading systems based on quantum principles and artificial intelligence. The author describes the development of a unique neural network that goes beyond classical machine learning by combining quantum mechanics with modern AI architectures.
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Automating Classic Market Methods in MQL5 (Part 2): Wyckoff Cause and Effect—Point and Figure Price Targets

Automating Classic Market Methods in MQL5 (Part 2): Wyckoff Cause and Effect—Point and Figure Price Targets

This article builds a self-contained MQL5 Expert Advisor that completes the Wyckoff cycle: it detects accumulation/distribution with a finite state machine, enters at the last point of support/supply, and calculates exit point-and-figure counts under Wyckoff's Cause and Effect. We detail the box size from range ATR, a 1-box reversal, target validation, and a 2R fallback. Readers get runnable code without external dependencies.
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MQL5 Wizard Techniques you should know (Part 95): Using Disjoint Set Union and Deep Belief Network in a Custom Signal Class

MQL5 Wizard Techniques you should know (Part 95): Using Disjoint Set Union and Deep Belief Network in a Custom Signal Class

For this article we switch to a custom MQL5 Wizard class that examines entry Signals. Our custom class is ‘CSignalDSUDBN’ this time around, and is coded by combining the Disjoint Set Union algorithm with a Deep Belief network. As has been the case throughout these series, our model is testable with MQL5 Wizard-Assembled Expert Advisors that can be tuned with different trailing stops and money management classes.
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Meta-Labeling the Classics (Part 2): Filtering and Sizing ADX Trades

Meta-Labeling the Classics (Part 2): Filtering and Sizing ADX Trades

The DI crossover often triggers in ranges where +DI and -DI oscillate without persistence. We build a two-layer hybrid: Optuna's TPE optimizes a regime gate over ADXR threshold, DI lookback, and minimum DI separation to maximize signal precision on a held-out window, then a Random Forest uses eleven ADX-derived features to accept or scale entries via afml.bet_sizing. The result filters ranging-market bursts and calibrates position size on EURUSD H1.
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From Basic to Intermediate: Objects (I)

From Basic to Intermediate: Objects (I)

In this article, we will begin looking at how to work with objects directly on the chart. This is done using code specially developed for demonstration purposes. Working with objects is very interesting and can be a lot of fun. Since this will be our first contact with the topic, we will start with something very simple.
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Trading with the MQL5 Economic Calendar (Part 11): Modular Canvas News Dashboard

Trading with the MQL5 Economic Calendar (Part 11): Modular Canvas News Dashboard

We rebuild the MQL5 Economic Calendar dashboard from a monolithic object-based panel into a modular canvas-based system split across four files. The update adds a dual light and dark theme, collapsible day groups, a resizable layout with pixel-based scrolling, revised value markers, and a live countdown with toast notifications. A candidate event cache and a fast-path timer that repaints only changed cells improve responsiveness and make the codebase easier to extend.
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Engineering a Self-Healing Expert Advisor in MQL5 (Part 2): Restart-Safe Virtual Trade Protection

Engineering a Self-Healing Expert Advisor in MQL5 (Part 2): Restart-Safe Virtual Trade Protection

Build a restart-aware virtual protection layer on top of the SQLite persistence from Part 1. The EA reconstructs hidden stop-loss and take-profit after restart, verifies current price against recovered exits, and closes or continues positions accordingly. The result is a consistent recovery path that detects managed positions and sustains safe runtime management.
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Competitive Learning Algorithm (CLA)

Competitive Learning Algorithm (CLA)

The article presents the Competitive Learning Algorithm (CLA), a new metaheuristic optimization method based on simulating the educational process. The algorithm organizes the population of solutions into classes with students and teachers, where agents learn through three mechanisms: following the best in the class, using personal experience, and sharing knowledge between classes.
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The MQL5 Standard Library Explorer (Part 14): Building a Dynamic Hedge EA with the ALGLIB Port (ap.mqh)

The MQL5 Standard Library Explorer (Part 14): Building a Dynamic Hedge EA with the ALGLIB Port (ap.mqh)

This article introduces ap.mqh, the ALGLIB port for MQL5, and demonstrates its use in multi‑asset workflows that require robust linear algebra. It covers why built-in indicators fall short, then implements polynomial regression, a rolling correlation matrix indicator, and an adaptive hedge ratio estimator using ridge regression with Cholesky. Practical code shows how to compute spread z‑scores and execute coordinated pairs trades entirely within MetaTrader 5.
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Market Microstructure in MQL5 (Part 2): Measuring long memory in MQL5 with Hurst estimators

Market Microstructure in MQL5 (Part 2): Measuring long memory in MQL5 with Hurst estimators

Part 2 focuses on practical long-memory detection for intraday data. Three complementary Hurst estimators are implemented and combined into a confidence‑weighted composite, with confidence tied to valid regression scales. The final H and confidence populate the shared analysis struct, enabling indicators to act only when H departs from the neutral 0.40–0.60 band and to select trend‑following above 0.60 or mean‑reversion below 0.40.
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Integrating MQL5 with Data Processing Packages (Part 9): Entropy-Based Adaptive Volatility

Integrating MQL5 with Data Processing Packages (Part 9): Entropy-Based Adaptive Volatility

This work presents an end-to-end pipeline: collect MetaTrader 5 data, engineer entropy/volatility/trend features, train a PyTorch classifier, and expose predictions through a Flask API. An MQL5 EA posts rolling prices each tick, receives probability and regime, and applies adaptive position sizing and stop distances. The result is a clear recipe for integrating ML inference with MetaTrader 5.
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Beyond GARCH (Part IV): Partition Analysis in MQL5

Beyond GARCH (Part IV): Partition Analysis in MQL5

In this article, we shift from Python research to native MQL5 engineering. We build the first module of the MMAR library: a shared constants header, an SVD-based OLS regression class, a Generalized Hurst Exponent estimator, and the partition analysis engine that computes the partition function, extracts tau(q), estimates H via zero-crossing interpolation, and scores multifractality through three diagnostic tests. Tested on 500,000 bars of EURUSD M10, the engine correctly classifies the data as multifractal in under four seconds. Part 4 of an eight-part series. Part 5 fits the tau(q) curve to four candidate distributions via the Legendre transform.
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Downloading International Monetary Fund Data Using Python

Downloading International Monetary Fund Data Using Python

Downloading international monetary fund data in Python: Mining IMF data for use in macroeconomic currency strategies. How can macroeconomics help an ordinary and an algorithmic trader?
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From Basic to Intermediate: Definitions (II)

From Basic to Intermediate: Definitions (II)

In this article, we will continue our awareness of #define directive, but this time we will focus on its second form of use, that is, creating macros. Since this subject can be a bit complicated, we decided to use an application that we have been studying for some time. I hope you enjoy today's article.
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Building an Object-Oriented ONNX Inference Engine in MQL5

Building an Object-Oriented ONNX Inference Engine in MQL5

This article shows how to run Python-trained models natively in MetaTrader 5 via the terminal's ONNX functions. We build an MQL5 class that encapsulates session creation, fixes input/output tensor shapes, applies min-max feature normalization to mirror training, and executes OnnxRun once per bar to protect the CPU, the result is a reliable, maintainable inference path for live charts and the Strategy Tester without sockets or DLLs.
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From Basic to Intermediate: Template and Typename (II)

From Basic to Intermediate: Template and Typename (II)

This article explains how to deal with one of the most difficult programming situations you can encounter: using different types in the same function or procedure template. Although we have spent most of our time focusing only on functions, everything covered here is useful and can be applied to procedures.
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Building an Object-Oriented Z-Score Statistical Arbitrage Engine in MQL5

Building an Object-Oriented Z-Score Statistical Arbitrage Engine in MQL5

This article shows how to implement a production Z-Score engine in MQL5 using an object-oriented include file, the library computes a rolling mean and population standard deviation, exposes a shift parameter for historical queries, and avoids redundant tick work by running on bar close. An Expert Advisor executes rule-based entries at positive/negative sigma thresholds and closes on mean reversion; a custom indicator provides visual verification.
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MQL5 Trading Tools (Part 39): Adding a Pinned-Tools Ribbon for Quick Access to Favorite Tools

MQL5 Trading Tools (Part 39): Adding a Pinned-Tools Ribbon for Quick Access to Favorite Tools

We add a pinned-tools ribbon: a floating bar that exposes frequently used tools for one-click access without reopening the sidebar. The article implements the ordered pin set and its API, an anti-aliased pushpin control in the flyout, and the ribbon with offscreen clipping, user-resizable width, and horizontal scrolling. The result is faster activation of favorite tools from a draggable, resizable ribbon on the chart.
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CSV Data Analysis (Part 5): Real-Time CSV Streaming from Live MetaTrader 5 Sessions

CSV Data Analysis (Part 5): Real-Time CSV Streaming from Live MetaTrader 5 Sessions

This article describes a live data export framework for MetaTrader 5 built around a decoupled, three‑layer design. The MQL5 component batches bar and tick records via a write buffer and rotates CSV files daily; a Python daemon tails the stream, renders a live dashboard, and flags anomaly thresholds. The demo indicator illustrates integration points, enabling real‑time monitoring and auditability during trading sessions.
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MQL5 Trading Tools (Part 40): Adding SQLite Persistence and Per-Timeframe Visibility to the Canvas Drawing Layer

MQL5 Trading Tools (Part 40): Adding SQLite Persistence and Per-Timeframe Visibility to the Canvas Drawing Layer

We add SQLite persistence to the canvas tools, saving every drawing and the entire UI session per symbol, then restoring them on startup so the workspace resumes exactly where you left it. The article builds versioned object serialization, a load/save lifecycle with dirty writes, and a timeframe-visibility editor that drives render-time filtering. The toolkit also runs as an indicator, so it can sit alongside other indicators or an Expert Advisor.
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Foundation Models for Trading (Part I): Porting Kronos to Native MQL5

Foundation Models for Trading (Part I): Porting Kronos to Native MQL5

Kronos is a pretrained transformer that models OHLCV bars the way a language model predicts words. We reimplement its tokenizer/encoder and transformer block in native MQL5, export weights to flat .bin files, and remove Python from runtime entirely. Part 1 delivers preprocessing and BSQ tokenization plus a bit-for-bit verification harness against PyTorch, so you can run the encoder inside MetaTrader 5 with confidence.
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Neural Networks in Trading: Hierarchical Skill Discovery for Adaptive Agent Behavior (HiSSD)

Neural Networks in Trading: Hierarchical Skill Discovery for Adaptive Agent Behavior (HiSSD)

In this article, we explore the HiSSD framework, which combines hierarchical learning and multi-agent approaches to create adaptive systems. We examine in detail how this innovative methodology helps uncover hidden patterns in financial markets and optimize trading strategies in decentralized environments.
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Beyond the Clock (Part 2): Building Runs Bars in MQL5

Beyond the Clock (Part 2): Building Runs Bars in MQL5

We implement tick-, volume-, and dollar-runs bars in Python and MQL5 and align them with the existing bar‑building framework. The article details the dual‑accumulator update, offline calibration with per‑side seeds, state persistence for EAs, and parity verification to match Python and MQL5 outputs. Runs bars expose one‑sided bursts that net imbalance can hide, improving coverage during quiet sessions and for mean‑reversion models.
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Designing a Strategy State Machine in MQL5: Replacing Nested If-Else Logic with Formal States

Designing a Strategy State Machine in MQL5: Replacing Nested If-Else Logic with Formal States

Nested if-else logic inside OnTick() creates implicit states that are hard to isolate, debug, and extend without regressions. A formal finite state machine in MQL5 uses an IState interface, a CStrategyContext mediator, and four concrete states to separate detection from behavior. A three-file include structure resolves circular dependencies and keeps declarations, definitions, and instantiation clean, making changes safer and debugging faster.
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Defining your Edge (Part 2): Using Divergence Mapping and a Temporal Fusion Transformer in a Trading Robot

Defining your Edge (Part 2): Using Divergence Mapping and a Temporal Fusion Transformer in a Trading Robot

In this article we make the case for merging Divergence Mapping with a Temporal Fusion Proxy in a Trading Robot. Rather than depending on lagging price confirmations, the Divergence Mapping's thesis is that acting like a structural sensor can help identify hidden momentum shifts from price action and indicator anomalies. To establish how these anomalies are interpreted over time we use a Temporal Fusion Transformer proxy. This network incorporates historical context to weigh developing trends such that merging it with Divergence Mapping should set us up to spot shifts in accumulation and distribution before price breakouts.
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Implementing a Circular Buffer Class in MQL5: Fixed-Memory Rolling Windows for Real-Time Indicator Calculations

Implementing a Circular Buffer Class in MQL5: Fixed-Memory Rolling Windows for Real-Time Indicator Calculations

A templated CCircularBuffer class for MQL5 replaces the O(n) ArrayCopy array-shift pattern with O(1) insertion using a fixed-capacity ring buffer. The implementation is shown end to end and integrated into a rolling standard deviation indicator. Benchmarks across multiple window sizes compare both approaches and quantify the impact on real-time indicator calculations.
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Feature Engineering for ML (Part 10): Structural Break Tests in MQL5

Feature Engineering for ML (Part 10): Structural Break Tests in MQL5

We port AFML Chapter 17 structural break tests to MQL5 as a single include, CStructuralBreaks, delivering six bar-indexed features for EAs: CSW statistic and critical value, Chow-Type DFC, SADF with a rolling lookback (default 252), SM-Exp, and SM-Power. SADF uses O(L²) rolling windows for real-time viability. A companion StructuralBreaksViewer indicator plots all series with per‑series visibility and optional z‑score normalization. SB_EMPTY marks invalid values for safe integration.