A Simple Limit-Order Market-Making EA and Its Inventory Risks
Summary
The article explains market making as providing two-sided quotes that support liquidity, while noting that market makers face inventory risk when price moves against accumulated positions. It contrasts this role with automated market makers used by decentralized exchanges and discusses how spreads can widen when liquidity providers withdraw during holidays, unusual activity, or major news. These sections provide general context rather than a detailed analysis of market structure. The implementation described is a basic MQL5 expert advisor that maintains buy-limit and sell-limit orders across selected currency pairs, with configurable order spacing, size, profit settings, and order limits. The author tests the EA on several currency pairs over a stated period and reports that drawdowns are large relative to profits. The article characterizes the approach as similar to a grid system and warns that the absence of protective exits leaves it exposed to extreme market moves. Its reported test outcome is a caution about this simple design, not evidence that market making is reliably profitable.
Key ideas
- Market makers supply two-sided quotes, but can accumulate inventory that loses value during sharp price moves.
- The article’s EA keeps buy-limit and sell-limit orders active using configurable spacing and order settings.
- The example tests the approach on multiple currency pairs over a stated historical period.
- Reported drawdowns are large relative to profits, and the design behaves similarly to a grid system.
- Without protective exits, the EA remains exposed to severe adverse price moves.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.