History of MQL5.community development

In this article, we will refine the graphics library classes by adding a vertical header to the table and use the table classes to create an indicator that displays the correlation between the symbols specified in the settings.

We present a rule-set-aware calibration chain that turns the remaining risk budget into a calibrated sigmoid scale for position sizing. It computes a ceiling from stop loss pct and safety factor, back-solves w at a reference divergence, and flattens size progressively as the budget shrinks. The paper also clarifies where leverage caps must be applied in production: at the lots conversion, since risk-based sizing alone does not enforce max leverage.

The article shows how to tune ICA hyperparameters with a supervised evaluation pipeline and apply spectral clustering to time-lagged indicators. Cross-validation identifies the optimal number of clusters, which are translated into expected return and risk measures. These signals drive dynamic position sizing and stop-loss control, with surrogate models converted to ONNX and integrated into an MQL5 Expert Advisor.

This article implements a lock-free shared-memory bridge in MetaTrader 5 that writes ticks in Apache Arrow’s columnar layout via the C Data Interface. It details the column layout, double buffering with a seqlock, and a batching strategy. You get full source for a writer class, a streaming Expert Advisor, and a self-test script that validates correctness before any Python reader is involved.

This article develops a market‑structure‑driven intraday breakout system based on Bill Williams fractals. We define session bounds, derive volatility‑scaled stops, use fixed risk and take‑profit multipliers, and limit trades to one per direction. An MQL5 Expert Advisor, visualization and statistics, tick-level backtests, an ORB comparison, and a cross-asset forward test provide a complete, replicable workflow.

In this article, I will show you, dear reader, how to select the objects we create on the chart and modify the position indicator so that it can perform many more functions than originally intended. We will look at how to implement the ability to move price levels and create price lines directly on the chart. Many people may find this difficult. However, you will see that we'll do this with minimal effort. You just need to give it a little thought.

In this article, we will take the next step in understanding what a linked list is and how it works. Although the content of this article may seem rather complex and confusing to beginners, I will try to explain it in the simplest terms possible. This will help you understand why and when to use linked lists.

Hardcoded prop-firm rules lock the sizer to one program. This article factors those rules into a PropFirmRuleSet and refactors PropFirmAccountState and the sizing modifiers to consume it, including dynamic versus fixed daily limits and the news-window profit-credit haircut. Parity against the original FundedNext behavior is validated on a simulated equity path, so you can retarget sizing by configuration instead of rewriting code.

We need a way to handle the graphical objects we create. The approach presented in the previous article works very well for certain scenarios. In this case, we will need something more complex, given the specific nature of the problem at hand. Therefore, we will not attempt to replace the ZOrder management mechanisms already present in MetaTrader 5, nor, of course, will we check which object is in the foreground or covered by another object. We are going to do something completely different. Here, I will show you what changes need to be made to the code in order to use part of what MetaTrader 5 already does for us.

This is an article that you, dear reader, should study carefully. That is due to the nature of the material presented here. Although we have tried to present the material as simply and informatively as possible, the information provided here can certainly seem quite complex to those who are just beginning to learn programming. Nevertheless, this is no reason to lose heart or ignore what is explained here, as this article will establish a link between two completely different, though closely related, topics.

This article shows how to build an interactive bar replay tool in MQL5 for MetaTrader 5 that reveals historical candles one by one without exposing future data. You will implement custom candles with DRAW COLOR CANDLES, an event-driven engine with OnChartEvent and OnTimer, a dashboard with Play/Pause, a draggable replay anchor, and Buy/Sell paper trading with SL/TP lines, while keeping the active bar in view to practice discretionary analysis and execution.

We introduce a persistent bookmark layer for the MetaTrader 5 History Navigator. Bookmarks capture a chart's symbol, timeframe, and historical position with a name and notes, write them to a CSV file, and reload them later without manual date entry. The implementation integrates bookmark management into the current navigation engine, enabling quick creation, selection, navigation, and deletion for efficient historical study.

In this turning-point article, we will begin to explore in greater depth the interaction between the applications we are developing to ensure full support for the replay/simulation system. Here we will analyze a problem that, on the one hand, is quite unpleasant, but on the other hand, is very interesting to explain and solve. The problem is this: how can we restore the take-profit and stop-loss lines after they have been deleted, and do so without using the terminal by performing the operation directly on the chart? At first glance, it seems simple. However, there are several obstacles that must be overcome.

In this article, we'll begin exploring a short series of concepts that are of immense importance to anyone who truly wants to learn how to program properly. Since this may seem very complicated at first—even though it is based on simple elements—we will go through the material step by step. So, let's start by figuring out what queues are.

The article examines the Hamiltonian Monte Carlo (HMC) algorithm — the gold standard for sampling from complex multivariate distributions. A full-featured implementation of HMC in MQL5 is presented, including adaptive mass matrix tuning, MAP estimation using the L-BFGS optimization method, and comprehensive diagnostics.

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.