EA Maintenance: Monitoring, Updates and When to Intervene

An expert advisor is a machine that breaks quietly. EA maintenance is the discipline that finds the break before the account does: daily, weekly and monthly checks, a habit of comparing the live equity curve and drawdown against expectations, and clear criteria for when to update the system, when to leave it alone and when to stop it entirely. This post covers each part, from the check routines to the documentation habits that keep maintenance honest.

EA maintenance: the daily, weekly and monthly routine

Maintenance runs on a cadence, because irregular checking converts small problems into large ones. The daily check takes five minutes and covers the machine: the terminal is connected, the EA is enabled, the error log is empty, positions are consistent with the strategy and alerts reach your phone. That is all. Daily checking never involves decisions about the strategy itself — those belong to the weekly review, when the record is complete.

The weekly review compares the week against the plan: equity movement, drawdown against the agreed maximum, realised slippage and spreads against the forward-testing assumptions, and a one-line note on market conditions. The monthly review is the bigger picture: drawdown against the tested maximum, correlation with other strategies, settings changes and a broker-terms check. The trade journal guide details the format and the patterns it exposes.

EA maintenance: equity curve and drawdown versus expectations

The equity curve is the most informative object in maintenance, because it answers whether the system is working as designed. Drawdown is measured from peak to trough, then compared with the maximum the strategy produced in testing, plus a margin. Inside the plan means no action, whatever the week felt like. Outside it triggers an investigation — a review of records, not an impulse to change settings.

Two failures masquerade as each other here. Drawdown from a market regime shift means the conditions left the strategy; drawdown from settings drift means the system changed. The equity curve cannot tell them apart — the journal can, because it records market conditions and settings changes side by side. That is why the forward testing baseline is established before deployment.

EA maintenance: broker changes that break expert advisors

Brokers change their terms without much notice. Spread widening reduces trade frequency and can stop a scalping EA from opening at all; commission changes alter the profit arithmetic the strategy was tested on; execution model changes convert instant fills into requotes. Symbol renames and server migrations disconnect the EA from its instruments entirely, margin and leverage adjustments alter lot sizing, and stop-out level changes convert a manageable drawdown into a margin call.

The defence is a monthly broker-terms check and a standing rule: any broker notice triggers a re-read of the EA’s assumptions against the current account terms. The FCA’s CFD guidance and the ESMA risk analysis document how those terms and costs can change.

EA maintenance: platform updates and version control

MetaTrader updates are frequent and mostly invisible — until one changes order handling or alters a function the EA depends on. Never let the platform update itself mid-week on a live terminal: install updates on a demo terminal first, run the EA there for a few days, then update live. The same rule applies to the EA file itself: keep a versioned copy of every EA and its settings, never overwrite the running version, and test new builds on demo before they touch live money.

Version control is where documentation and software meet. Every change — a platform update, a settings tweak, a new build — gets a dated entry with the previous value and the reason. If a change is not in the log, it did not happen; if it cannot be justified by the log, it is the beginning of over-optimisation, not maintenance. The start here guide covers the account and platform fundamentals.

EA maintenance: when to stop a strategy — regime change

Stopping is a decision, not a feeling, and the criteria must be written down before deployment, because during a drawdown every decision feels urgent. Three triggers justify stopping: the market conditions the strategy was designed for no longer appear; drawdown exceeds the maximum agreed in advance; or the cost and error picture shows the system cannot execute as assumed at your broker. Each is verified against the records before it is acted on.

Regime change deserves a distinction, because it is the most common legitimate stop. A strategy is designed for a condition set, and when the market leaves it, the strategy will lose regardless of how well it is maintained. The record — stable settings, decaying performance, drifting conditions — shows the market moved, not the system. That distinction is what the CFTC’s investor education material warns retail traders to look for before more capital is committed.

EA maintenance: documentation habits that keep records honest

Documentation is the part of the discipline most traders skip. Three habits cover the need. First, a change log with date, previous value and reason for every modification — recorded before the change, not after. Second, the forward-testing baseline for equity, drawdown and slippage, kept permanently so live data always has its reference point. Third, a weekly market-condition note, even when nothing happened — a blank market column over months is itself the signal that conditions have drifted.

Maintenance works because it is boring: the same checks, the same cadence, the same records, for as long as the strategy runs. It buys the ability to tell the difference between the market changing and the system changing — the question emotional trading always gets wrong.

Frequently asked questions about EA maintenance

How often should I check my expert advisor?

Daily checks take five minutes: terminal connected, EA enabled, no error log entries, positions consistent and alerts reaching your phone. Weekly checks compare equity, drawdown, slippage and spread against the plan. Monthly checks review the full picture: drawdown versus the tested maximum, correlation with other strategies and settings drift. The cadence is the discipline — irregular checking converts small problems into large ones.

What broker changes can break my expert advisor?

Spread widening, commission changes, execution model changes, symbol renames, new servers, margin adjustments and stop-out level changes all break EAs in different ways — from reduced trade frequency to failed orders to mass margin calls. Since brokers can change terms with little notice, the routine includes a monthly broker-terms check and a rule that any broker notice triggers a re-read of the EA’s assumptions.

When should I stop a strategy for good?

Stop when the conditions the strategy was designed for no longer appear, when drawdown exceeds the maximum agreed in advance, or when the cost and error picture shows the system cannot execute profitably at your broker. The criteria must be written down before deployment, because during a drawdown every decision feels urgent. The difference between regime change and over-optimisation is visible only in the records.

What documentation should I keep for EA maintenance?

A versioned copy of every EA file and its settings, a change log with date, previous value and reason for every modification, the forward-testing baseline for equity, drawdown and slippage, and a weekly market-condition note. Documentation makes a maintenance decision defensible rather than emotional — the trade journal routine covers the full structure.

Maintain on a schedule, not on a scare. Set up the daily, weekly and monthly routine before your next deployment — the automation playbook lays out the monitoring, broker checks and review cadence for every EA you run.

Risk disclosure: Trading foreign exchange, commodities, CFDs and cryptocurrencies carries a high level of risk and may not be suitable for all investors. Past performance is not indicative of future results. AlgoTM provides trading tools and technology only and does not provide investment advice, portfolio management or guaranteed returns.