Professional financial traders have always had sophisticated tooling — Bloomberg terminals, level 2 order books, real-time technical analysis. Betfair exchange traders, operating in a market with the same underlying dynamics as financial exchanges, largely did not. e-Trends was built to close that gap: a dedicated trading application that gave Betfair traders the kind of interface and analytical tooling that the exchange’s own client couldn’t provide.
The Problem with the Default Interface
Betfair’s own web interface was designed for casual punters placing individual bets, not for traders actively managing positions, reading market momentum, and executing at speed. It showed prices, but it didn’t show the depth of the order book. It didn’t visualise how prices had moved over time. It gave you no analytical layer on top of the raw numbers.
For anyone trading seriously — looking to identify price trends, enter and exit positions at the right moment, and manage multiple runners simultaneously — the default interface was a significant constraint. e-Trends was the answer.
The Ladder Interface
The centrepiece of e-Trends was the ladder display — a real-time, scrollable price ladder for each runner in a market showing the full depth of the order book at every available price point.
Each row of the ladder represented a specific price. Columns showed the available back money, the available lay money, and the traded volume at that price — updated live as the market moved. The visual layout made it immediately obvious where liquidity was concentrated, where the market had been, and where it was likely to go. Clicking a cell placed an order directly at that price, making execution fast and precise rather than a process of typing values into form fields.
For in-play trading — where prices can move within seconds and the ability to react quickly is directly profitable — the ladder was transformative compared to the standard interface. Experienced traders who used it reported a material improvement in their ability to read market structure and execute at the right moment.
Technical Indicators and Charting
Beyond the ladder, e-Trends provided a configurable charting layer for each runner, plotting price history and derived indicators over the duration of the market.
Moving averages were the core offering — short, medium, and long-term simple and exponential moving averages plotted over the price series, allowing traders to identify trend direction and momentum at different timescales. A price crossing above its short-term moving average in a contracting market tells a different story from the same event in an expanding one; having all three timeframes visible simultaneously gave traders the contextual picture they needed.
The charting was interactive — traders could configure which indicators were displayed, adjust the timeframes, and zoom into specific periods of the market’s lifecycle. The goal was to give each trader the analytical setup that matched their strategy rather than forcing a one-size-fits-all view.
Technology
e-Trends was a Java desktop application built with Swing for the UI. Real-time market data was consumed from the Betfair Exchange API — initially over SOAP, later adapted as Betfair evolved their API offering — with a local update loop driving the ladder and chart displays on each tick. JFreeChart provided the charting foundation, extended with custom renderers for the Betfair-specific data model and the indicator overlays.
The performance requirements were non-trivial. A live Betfair market can produce dozens of price updates per second across multiple runners in the minutes before a race goes off, and in-play the frequency increases further. The UI had to process and render those updates without introducing visible lag — because for a trader watching a ladder, a display that’s even a second behind the market is useless. Threading, update batching, and render optimisation were significant parts of the engineering work.
The Betfair API integration handled authentication, market subscription, order placement, and position tracking — the full suite of operations needed to use the application as a complete trading environment rather than just a display tool.
Market Context
The Betfair trading tools market has since grown into a commercial ecosystem — Bet Angel, Gruss Betting Assistant, Geeks Toy, and others have all built substantial businesses serving exactly this audience. e-Trends was operating in this space early, before those tools had reached maturity, and addressed the same fundamental need: giving traders a professional-grade interface for a market that deserved one.
The experience of building it — designing a real-time data display with sub-second refresh requirements, implementing technical analysis indicators over a live price series, and creating an order placement workflow that traders would trust with real money — was foundational to the trading framework work that followed, and directly informs how I think about low-latency, data-intensive system design today.
Betfair API
JFreeChart
Betfair Exchange
Trinity Logic Ltd