Custom MT5 Expert Advisor Development
Send us your trading rules and we turn them into an Expert Advisor for MetaTrader 5 or MetaTrader 4. We write it in MQL5 or MQL4, test it on real tick data, forward-test it on a demo account and hand over the source code. The same team builds and runs QuantFX's own C++ trading engine, so you get production engineering rather than a quick script.
What we build
- Expert Advisors from your rules
- Entry, exit, filters, position sizing and trade management, coded exactly as specified. If a rule is ambiguous we ask before we write it, so the EA does what you meant.
- Gold (XAUUSD) and FX EAs
- Logic that copes with gold's wide and changing spreads, broker stops-levels, session opens and news spikes. We run our own XAUUSD strategies, so these edge cases are familiar.
- Prop-firm-ready risk logic
- Daily loss and maximum drawdown guards, equity-based lockouts, news and weekend filters, and consistency rules, enforced inside the EA rather than left to the trader.
- Indicators, scripts and utilities
- Custom indicators, trade managers, dashboards, alerts and order tools for MT5 and MT4, including multi-symbol and multi-timeframe logic.
- MQL4 to MQL5 conversion
- We port MT4 EAs to MT5 and rewrite the order handling for MT5's netting and hedging account modes, then check the two versions match in the tester.
- Audits and fixes of existing EAs
- We review an existing EA's code, find why it behaves differently live than in the tester, and fix order errors, slippage handling and requote logic.
How a project runs
- 01
Specification
We go through your rules with you and write them up as a short specification. You confirm it before any code is written, and the quote is fixed against it.
- 02
Build
We code the EA in MQL5 or MQL4 with clear inputs, logging and error handling. Order sending, retries and broker limits are handled explicitly.
- 03
Strategy tester
We test on real tick data with your broker's spreads and costs, and show you the reports. The aim is to check the EA follows the rules, not to tune parameters until the curve looks good.
- 04
Forward test
The EA runs on a demo account under live market conditions, so differences between tester and live execution show up before real money is involved.
- 05
Handover and support
You get the source code, the compiled file, the documentation and the test reports. We fix bugs found after delivery and can take on changes as a follow-up project.
What you receive
- Full MQL5 or MQL4 source code (.mq5 / .mq4) and the compiled EA (.ex5 / .ex4)
- The agreed specification, kept as the reference for the build
- Strategy tester reports on real tick data
- Forward-test log from a demo account
- A short user guide covering every input
- Bug-fix support after delivery
Why companies and traders use QuantFX
- Engineers who run their own strategies
- QuantFX builds and operates its own systematic strategies on MT5 and a low-latency C++ engine. We know what breaks when an EA meets a live broker.
- Testing that looks for problems
- Walk-forward checks, out-of-sample periods and cost modelling are part of how we work. We would rather show you a weak result than an overfitted one.
- Beyond MQL when you need it
- When an EA needs heavy computation or external data, we connect it to C++ or Python through a DLL or a bridge, built by the same team.
- A UK company with clear terms
- QUANT-FX INFRASTRUCTURE LTD is registered in England and Wales. We never hold or manage client money; you run the EA on your own account at your own broker.
Example: an in-house XAUUSD EA
One of our own gold EAs trades XAUUSD on MT5 with session filters, spread checks before every order and hard daily-loss limits written into the code. It was built the same way as a client project: specification, real-tick testing, demo forward test, then live monitoring.
We keep it in production as a working reference for how we handle gold's spread spikes and broker stops-levels. The figures from our master account, in a broker demo environment, are on the track record page.
How pricing works
Every EA is quoted at a fixed price after we have read your rules and agreed the specification. Price depends on the number of rules and filters, the risk and trade-management logic, the number of symbols and whether you need MT4 and MT5 versions. We are not the cheapest option on a freelance marketplace. You pay for tested, documented code that you own, and for engineers who stay available after delivery.
Frequently asked questions
- Do I own the source code of my Expert Advisor?
- Yes. You receive the full .mq5 or .mq4 source code along with the compiled file. We do not lock EAs to our servers or resell your strategy.
- Can you build an EA for MT4 as well as MT5?
- Yes. We build in MQL4 for MetaTrader 4 and in MQL5 for MetaTrader 5, and we can convert an existing MT4 EA to MT5.
- How long does a custom EA take?
- A simple EA with a few rules usually takes one to two weeks including testing. EAs with complex trade management, several symbols or external integrations take longer; the timeline is set in the specification.
- Will the EA pass a prop firm challenge?
- No developer can promise that. We can build the firm's rules into the EA, such as daily loss and maximum drawdown limits, so the EA itself never breaks them. Whether the strategy is profitable depends on the strategy.
- Do you guarantee profits?
- No. We build and test the EA to follow your rules precisely and handle live execution properly. Trading results depend on the strategy and the market, and past or tested performance does not guarantee future results.
- Do you sell ready-made EAs?
- No. Every EA is custom work for one client. We also build and license our own systematic strategies to companies; see the technology page for that.
Have trading rules you want turned into an Expert Advisor? Send them over and we will come back with a specification and a fixed quote.
Request a quoteTrading leveraged products such as CFDs and FX carries a high risk of loss. QuantFX provides software development services only; we do not give investment advice and do not hold or manage client funds.