Steve Stagg

Contract lead developer

About Me

A versatile technologist with broad experience across many industries, and deep knowledge of software engineering. My work has saved companies millions of dollars, enabled new strategic opportunities, and has repeatedly gained formal recognition from industry bodies.

I have a passion for understanding the true nature of complex problems, and finding the most appropriate solution that balances cost, speed, technical rigour, and business need.

I'm as comfortable defining strategy and technical architectures for large-scale enterprise initiatives, as I am working with individual requirements to deliver small targeted solutions.


Contracts - Bank of America, Youview, Mosaic FM, BskyB, others 2013 - current
  • Developed the system that transformed Tier-1 investment bank’s transaction reporting from being a significant regulatory risk, to being awarded most accurate high-volume transaction reporting firm by Unavista in 2018. Since then this system has saved millions of dollars by avoiding compliance penalties across many global jurisdictions.
  • Real-time regulatory post-trade & transaction reporting engine using Python and numpy. Generating 10s of millions of daily reports from hundreds of millions of events, joining multiple external datasets and running thousands of rules. Average report published in 80ms. One-click, auditable, per-field lineage documentation generated by automated static analysis of rules.
  • Designed and implemented a full-stack system for self-service machine learning anomaly detection, based on streaming datasets. Working with ML expert to build intuitive, guided interface designed to be used by non-technical SMEs. Using scipy, sklearn, pandas, parquet, d3 and ag-grid. Detected systemic issues in upstream systems causing significant data quality issues.
  • Wrote highly optimized Cython Avro serialization library & recursive Python JIT to enable use of Python at required throughputs.
  • Revolutionized problem analysis in the department by implementing novel UI for visualising trade lifecycles, exposing complex timing-based issues in an easy-to-discover interface.
  • Brought in to troubleshoot and performance tune problematic Objective-C iOS app. In two days was able to deliver 5x performance gain in primary bottleneck. Delivered design plan for larger architecture improvements.
  • Developed state of the art hybrid NLP processing platform using Rust core with PostgreSQL plugin and Python library to allow complex user-driven NLP querying over large corpora of text. Spacy & LLM based processing performed with AWS Batch, with analysis in Jupyter and SQL (Tableau/Power BI).
  • Worked in a variety of agile & scrum teams, from sole-developer to 10-developer teams within larger departments.
Tech Lead (Head of Backend) - onefinestay 2017
  • Successfully led complete rewrite of complex website backend, to integrate multiple companies inventory and order management systems and support 3x inventory. Implemented using graphql and real-time feeds from external systems. Results: improved performance, reduction in operational issues & support. Project delivered successfully within two-month deadline.
  • Implemented novel flask based graphql interface using runtime automatic schema generation using type hinting. Advanced PostgreSQL based pricing calculation removed need for slow, high-maintenance search indexes.
  • Managed geographically distributed backend engineering team.
Software Engineer - Cmed Technology 2008 - 2012
  • Technical lead and engineer for an integration project that formed the nexus of a pivotal eSource trial that gained recognition from Microsoft, the FDA, SCDM, and the board of a top-tier Pharma company
  • Tech lead & Architecture for Django based web UI frontend. Replacing existing flagship UI. Handling clinical trial data, from scratch. Produced Design & Functional specifications that passed MHRA audit.
  • Product Management for major project, providing mockups, design specs and technical guidance to dev teams.
Web Development - Contract 2005 - 2008
  • Bespoke web site design. Web service and filtering technologies developed in PHP, C and C++.
  • Custom message-filter based MS Exchange email keyword scanning in C++ using Regex and Aho-corasick.
  • Recorded, printed, typeset, synthesized, published, and nationally sold school music book for local musician.


I try not to focus too much on particular technologies. Other factors typically are more important than which language or library is chosen. However my experiences tend to center around:



Christ's Hospital School - 1998 - 2004 Horsham, UK. Three A-Levels, English, Maths, and Physics.


Quanta Introduction to C++May 2005
CMI Introduction to ManagementJun 2005