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Back-end/Full-stack engineer with production experience in Python, Java, and Spring Boot, currently building front-office pricing systems at Barclays. I partner closely with traders, turning pricing requirements into reliable, high-performance APIs and services. Previously, I worked on backend services at Telicent and shipped end-to-end products as a solo engineer, including Stripe-powered marketplaces, ML voice-matching tooling using vector embeddings, and an LLM-enabled Chrome extension using RAG.…Back-end/Full-stack engineer with production experience in Python, Java, and Spring Boot, currently building front-office pricing systems at Barclays. I partner closely with traders, turning pricing requirements into reliable, high-performance APIs and services. Previously, I worked on backend services at Telicent and shipped end-to-end products as a solo engineer, including Stripe-powered marketplaces, ML voice-matching tooling using vector embeddings, and an LLM-enabled Chrome extension using RAG.

Joe Bailey

Back-End Developer, Full Stack Developer, Software Engineer, +3

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Back-end/Full-stack engineer with production experience in Python, Java, and Spring Boot, currently building front-office pricing systems at Barclays. I partner closely with traders, turning pricing requirements into reliable, high-performance APIs and services. Previously, I worked on backend services at Telicent and shipped end-to-end products as a solo engineer, including Stripe-powered marketplaces, ML voice-matching tooling using vector embeddings, and an LLM-enabled Chrome extension using RAG.…Back-end/Full-stack engineer with production experience in Python, Java, and Spring Boot, currently building front-office pricing systems at Barclays. I partner closely with traders, turning pricing requirements into reliable, high-performance APIs and services. Previously, I worked on backend services at Telicent and shipped end-to-end products as a solo engineer, including Stripe-powered marketplaces, ML voice-matching tooling using vector embeddings, and an LLM-enabled Chrome extension using RAG.

Available to hire

Back-end/Full-stack engineer with production experience in Python, Java, and Spring Boot, currently building front-office pricing systems at Barclays. I partner closely with traders, turning pricing requirements into reliable, high-performance APIs and services.

Previously, I worked on backend services at Telicent and shipped end-to-end products as a solo engineer, including Stripe-powered marketplaces, ML voice-matching tooling using vector embeddings, and an LLM-enabled Chrome extension using RAG.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Beginner

Beginner

Language

English

Advanced

Javanese

Fluent

Work Experience

Python & Java Developer at Barclays

January 1, 2026 - Present

Developed and maintained pre-trade pricing APIs and services in Python and Java for structured products and derivatives. Worked with traders to build and extend pricing tooling, and implemented performance improvements by optimizing ladder splitting in an existing Java microservice to increase concurrency of IO operations and instruction partitioning, targeting a large daily throughput and observed order-of-magnitude speedups. Investigated and fixed a production bug reported by traders by identifying root causes related to inconsistent access and adapter conventions; refactored Python adapters to use enum-based numbering instead of magic numbers and added test coverage across affected adapters. Implemented a certificate-as-wrapper as a valid legal configuration for Sharkfin products in the Python pricing service, extending wrapper options for structurers. Followed engineering standards including code reviews, automated testing, and CI/CD driven delivery.

Python & Java Developer (Front Office Pre-Trade Equity Derivatives and Structured Products) at Barclays (contracted via Inspire Talent / Capgemini)

January 1, 2026 - Present

Developed and maintained pre-trade pricing APIs and services in Python and Java for structured products and derivatives, working closely with traders to build and extend pricing tooling. Implemented ladder splitting in an existing Java microservice to increase performance by improving concurrency and partitioning IO operations and instructions, resulting in a reported ~10x daily auto-callable pricing performance improvement over a decade of observations. Investigated and fixed production issues reported by traders by identifying root causes related to inconsistent access/conventions in adapters; refactored adapters to use enums instead of magic numbers and added test coverage across affected components. Implemented certificate-as-wrapper as a valid legal configuration for Sharkfin products in the Python pricing service, extending wrapper options for structurers. Followed engineering standards through code reviews, automated testing, and CI/CD-driven delivery.

Junior Java Engineer at Telicent

May 1, 2024 - December 31, 2024

Built core Java backend services using Java 17 and Java collections. Implemented REST API endpoints for Smart Cache Tabular, enabling client integration and transforming RDF knowledge graphs into human-readable formats (Excel/JSON) using Apache POI and Jackson. Worked with RDF graphs and Apache Jena alignment with IES (Information Exchange Standard) for geospatial and temporal data integration. Developed a View RDF Assembler for constructing RDF graphs from predefined view definitions and associated data. Built backend services handling multipart requests for view definitions, including request model development and validation, PostgreSQL integration via JPA, RDF parsing and transformation, and Kafka-based event publishing for asynchronous processing across multiple backend services. Created comprehensive test suites using JUnit/TestNG/Mockito and containerized Docker environments for integration testing.

Software Engineer (UAS Life Cycle Management Project) at University of Warwick (simulated enterprise project with Sierra Nevada Corporation as client)

January 1, 2022 - January 1, 2023

Worked in an Agile/Scrum team and attended sprint and client meetings, acting as Scrum master in some sessions. Participated in requirement elicitation and created user story issues from requirements. In sprint end client meetings, presented progress and used retrospective feedback to generate new issues and user stories via GitLab. Owned design and implementation of specific issues across frontend (React), backend code (Java/Spring Boot), and database (MySQL) structure. Benchmarked performance and scalability of REST API with load testing (JMeter) and optimized using techniques such as database indexing and code optimization to reduce redundancy, significantly improving performance. Followed rigorous team standards including checkstyle, unit tests, and ensured code passed CI/CD build pipeline to Heroku.

CEO, Founder & Software Engineer at Fanplay (fan-play.com)

January 1, 2022 - January 1, 2023

Solely responsible for design, development, testing, and deployment of a SaaS MVP, including feature conceptualization and business model/strategy. Implemented automated payments and an escrow system using Stripe Connect. Deployed Spring Boot REST API to Heroku, the React frontend to Vercel, and used AWS RDS for the database and S3 for image storage in the cloud.

Software Engineer (UAS Lifecycle Management) at University of Warwick (Sierra Nevada Corporation simulated enterprise project)

January 1, 2022 - December 31, 2023

Worked in an Agile team using Scrum, created user story issues from requirement elicitation, and participated in sprint and client meetings. Acted as scrum master in some meetings. Owned design and implementation for specific issues including React frontend, Java/Spring Boot backend code, and MySQL database structure. Benchmarked and improved REST API performance and scalability via techniques such as database indexing and code optimization; employed team coding standards (e.g., Checkstyle) and implemented unit tests. Ensured code passed tests in CI/CD builds to Heroku.

CEO, Founder & Software Engineer at Fanplay

January 1, 2022 - December 31, 2023

Solely responsible for designing, developing, testing, and deploying a SaaS MVP. Defined product features and the business model/strategy. Implemented automated payments and an escrow system using Stripe Connect. Deployed a Spring Boot REST API to Heroku, the React frontend to Vercel, and used AWS RDS for the database and S3 for image storage in the cloud.