How we build things is just as important as what we build. These articles let our engineers explain the “why” of what we do, and how we put the “tech” in “FinTech”.


FastAPI and cooperative multi-threading

This post was first published in Cal Paterson wrote a great article comparing and describing synchronous and asynchronous Python frameworks and explaining why asynchronous frameworks go a bit wobbly under load. This is a story of how we experienced wobbliness in a recent project. We are using FastAPI, Pydantic, and...

February 10, 2022

RFC Driven Development

The ‘Request For Comment’ (RFC) process is often used in large open source projects to coordinate discussion, record requirements and  document design decisions. It is a process by which all contributors record suggestions, comments and discussions focussed around a technical proposal. The merit of the original proposal is debated, alternatives...

February 8, 2022

Optimizing Kafka producers for latency

This post was first published in The code I am working with uses Confluent Kafka Python library that calls librdkafka C++ library underneath. The code does synchronous messaging: it produces events one-by-one and ensures event is persisted in Kafka topic by waiting for acknowledgments from all replicas. This code is sensitive to latency...

January 28, 2022