Colin Cheung

Glasgow, UK - Working remotely. <colincheung25@gmail.com> | linkedin/colin-cheung/ | github.com/ColinCee | colincheung.dev>

Professional Profile

Senior Software Engineer with 8+ years of experience architecting, developing, and deploying high-impact, scalable full-stack solutions for complex business needs. Deep expertise in Node.js, React, TypeScript, and distributed AWS systems. Proven ability to lead projects, optimize engineering practices, drive innovation, and significantly enhance developer productivity and system performance. Passionate about mentorship and building highly available, resilient systems.

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Experience

EDF Energy - Senior Software Engineer (Contract) - Apr 2023 - Present

Technologies: TypeScript, Node.js, AWS (Lambda, SQS, SNS, DynamoDB, S3, Cognito), React, React Query, Zod, GitHub Actions

Developed and scaled solutions within Customer Complaints and Debt Collection, directly impacting debt recovery.

• Led migration of CI/CD pipelines (AWS CodePipeline to GitHub Actions) for a large monorepo, integrating Turborepo, slashing build/test cycles from 20 to 5 minutes.
• Led migration from JavaScript to TypeScript and implemented Zod for runtime validation, reducing runtime errors through static type checking and strict data validation.
• Enhanced the existing debt recovery state machine by developing additional customer journeys using its internal DSL, directly contributing to the recovery of significant amounts in debt..
• Developed a secure, high-performance React-based self-service portal, granting internal stakeholders direct access to critical ETL pipeline outputs and eliminating hours of daily ad-hoc development requests.
• Architected event-driven microservices for critical B2B integrations with Debt Collection Agencies, powering the engagement high-debt customers by automating the complete data exchange cycle: dispatching targeted customer visitation lists to guide DCA field operations, and processing their subsequent collection status updates into our state machine.
• Drove cost optimization by identifying and implementing DynamoDB Point-in-Time Recovery (PITR), saving several thousand USD in savings per month on AWS spend.

BBC - Senior Software Engineer (Contract) - Nov 2022 - Apr 2023

Technologies: Node.js, React, AWS (Lambda, DynamoDB, CDK), CI/CD

Improved developer productivity and engineering insights by enhancing internal tooling.

• Architected and implemented a serverless data pipeline using AWS CDK for tracking build failure statistics, enabling data-driven CI/CD optimization.
• Led a key developer experience initiative by automating PR comments with code coverage reports, reducing debugging time in CI logs by up to 90% and accelerating delivery.

Hopper - Software Engineer - Mar 2022 - Oct 2022

Technologies: Scala, Docker, Kubernetes (K8s), GCP (Pub/Sub), gRPC, React, Terraform, Datadog

Contributed to scaling customer service platforms during hyper-growth, handling high request volumes.

• Engineered and launched cross-vertical VIP support features, increasing service visibility by >200% and contributing to a 50% revenue uplift for related services.
• Developed and maintained business-critical Scala backend microservices serving 100k+ daily requests via gRPC.
• Implemented multi-tenancy in backend services using gRPC and GCP Pub/Sub for scalable asynchronous communication.
• Established robust service monitoring, SLOs, and alerting in Datadog using Terraform (IaC), ensuring high availability.

Hometree - Senior Software Engineer - Jun 2021 - Mar 2022

Technologies: React (Hooks), Node.js, TypeScript, AWS (Serverless Stack, RDS Proxy, CloudWatch), Cypress, React Testing Library, Buildkite, MikroORM

Led full-stack development initiatives and mentored engineers in a fast-paced startup.

• Led the greenfield redesign and modernization of a business-critical legacy checkout system using React (Hooks) and TypeScript, significantly improving UX, performance, and maintainability.
• Championed and embedded modern development practices: E2E testing (Cypress), Serverless Stack for IaC, CloudWatch Alarms for proactive monitoring, and Buildkite for robust CI/CD pipelines.
• Utilized Pair Programming and TDD (React Testing Library, Cypress, unit tests) to maintain high code quality and foster knowledge sharing.
• Drove migration to AWS RDS Proxy and MikroORM, enhancing database security by mitigating SQL injection vulnerabilities and enabling reliable transaction management.

Skyscanner - Software Engineer - Feb 2020 - Apr 2021

Technologies: Python, React, Docker, AWS (Lambda, SQS)

Managed sensitive employee data and developed HR automation tools.

• Engineered HRMS to Active Directory data synchronization (AWS Lambda, SQS), reducing update times from 8 hours to 2 minutes.
• Architected and developed an AWS Serverless Slack chatbot for HR feedback.

PodFather Ltd - Software Engineer - Jul 2017 - Feb 2020

Technologies: PHP, Android (Java/Kotlin), MySQL, TypeScript, Node.js, Docker, AWS S3

Full-stack development for a mobile ePOD application (10k+ daily drivers).

• Optimized Android image capture, improving processing speed by 300%.
• Successfully migrated Terabytes of image data from MySQL BLOBs to AWS S3.

Education

University of Strathclyde | Glasgow, UK - 2013 - 2018 BEng (Hons) Computer and Electronic Systems - 1st Class Honours

• Dissertation: “Investigating learning type algorithms for video games” (Focus on AI/Machine Learning)

Skills

• Programming Languages: TypeScript, JavaScript (Node.js), Python
• **Cloud Platform - AWS:**Lambda, SQS, SNS, DynamoDB, S3, Cognito, API Gateway, CDK, RDS, SST
• Backend Development: Node.js, Microservices, Event-Driven Architecture, REST APIs, gRPC
• Frontend Development: React, React Query, HTML5, CSS3, Electron
• Databases: DynamoDB, MySQL, PostgreSQL, MongoDB, ORMs (MikroORM)
• CI/CD, DevOps & Observability: GitHub Actions, Buildkite, Docker, Kubernetes (K8s), Terraform, Datadog, Prometheus, Grafana
• Testing & Quality: Jest, React Testing Library, Cypress/Playwright, TDD, Zod
• Other Tools: Git, JIRA, Monorepo tools Turborepo

Personal Projects

• TypeScript Discord Bot: Engineered a feature-rich Discord bot using TypeScript and Node.js, leveraging the Discord.js library for robust command handling and event management. Implemented real-time chat message processing to trigger dynamic voice clip playback. Deployed and self-hosted on a Raspberry Pi, optimizing for resource-constrained environments.
• Electron Chess App: Developed a cross-platform desktop chess application using Electron and React, providing a real-time, side-by-side move analysis overlay for popular online chess platforms. Integrated the Leela Chess Zero (Lc0) reinforcement learning engine via UCI protocol for advanced AI-powered insights during live gameplay.
• Self-Hosted Minecraft Server: Deployed a dedicated Minecraft server within a Dockerized environment on a low-power (6W TDP) Linux machine. Utilized Docker Compose to orchestrate services including Minecraft, Prometheus (for metrics collection: JVM performance, player count, TPS), Grafana (for customizable dashboard visualization), and Traefik (as a reverse proxy). Configured DuckDNS for dynamic DNS resolution to a home IP address, enabling public accessibility.