Available to hire
Hi, I’m Javier Mellado, a senior software engineer based in Edinburgh with 20+ years of experience delivering scalable web and mobile products across media, finance, public sector, and startups. I focus on the JavaScript/TypeScript ecosystem: Frontend with React and React Native (Redux), Backend with Node.js and GraphQL, and Cloud infrastructure on AWS (Lambda, DynamoDB, CDK) with CI/CD pipelines. I’m comfortable bridging technical and non-technical stakeholders and love building robust, maintainable systems.
I thrive in fast-moving environments, enjoy mentoring teams, and value clear communication in both English and Spanish. My experience spans large-scale products and smaller startups alike, and I’m motivated by shipping high-quality software and solving complex problems with pragmatic, collaborative approaches.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Language
Spanish; Castilian
Fluent
English
Fluent
Work Experience
Senior Software Engineer (Contractor) at ATG Entertainment UK
August 1, 2025 - August 1, 2025Designed and implemented AWS Node.js Lambda-based APIs integrating third-party systems and internal services. Developed infrastructure using AWS TypeScript CDK across environments. Worked with DynamoDB, RDS, and API Gateway to support high-throughput backend services. Improved monitoring and observability with New Relic metrics and structured logging. Collaborated with architects and product stakeholders to deliver secure, maintainable backend solutions.
AWS TypeScript Engineer (Contractor) at Registers of Scotland
September 1, 2024 - September 1, 2024Built and maintained serverless microservices using AWS Node.js Lambda, API Gateway, DynamoDB, and CDK. Migrated legacy registers toward cloud-based architecture. Delivered production-ready features through pair programming, TDD, and continuous integration. Ensured code quality and test coverage via unit testing, static analysis, and XP practices. Participated in collaborative design sessions, stakeholder workshops, and Agile ceremonies. Aligned with GDS/Digital First quality standards. Used CloudWatch and observability tools to monitor across environments.
Software Engineer at Starstock
May 1, 2022 - May 1, 2022Worked on a platform with GraphQL, React.js, Stripe, Django, styled components and Storybook. Helped transition from a standard web application to a web3 app in areas of integrating Solana and Ethereum wallets in the frontend.
Senior Software Engineer at Fanduel
October 1, 2021 - October 1, 2021Core frontend functionalities of Sportsbook apps (mobile and web) including geolocation, session management, and bet placements using React, React Native, Redux and RxJS. Involved from inception to release, monitoring with Kibana and Elasticsearch.
Full Stack Developer – React & PHP & AWS (Contractor) at People’s Postcode Lottery
April 1, 2020 - April 1, 2020Upgraded to latest Symfony version; modularised monolith into React SPAs with per-service CI/CD (Jenkins, AWS CDK, AWS CodeBuild, CodePipeline). Created Kibana dashboards and mentored the team on Elasticsearch.
Full Stack Developer – React & Node (Contractor) at Wipro (Lloyds Banking Group)
July 1, 2019 - July 1, 2019Supported pensions and retirement journey; improved accessibility devices, mobile-first approaches. Stack: React.js, Redux, Jest, Enzyme, Styled Components, Jenkins, Node, Koa.
Javascript Developer – React Native (Contractor) at UEFA
July 1, 2018 - July 1, 2018Part of the National Teams Competition team; Android and iOS apps for European Qualifiers, Euro2020, UEFA Nations League, UEFA Champions League and UEFA Europa League. Stack: React Native, Redux, Jest, Enzyme, Flowtype, Styled Components, Sentry, Bitrise.
Technical Lead (Contractor) at UEFA
July 1, 2018 - July 1, 2018Defend technical integrity of products by guiding the team, UEFA tech architect, and Product Owner to identify opportunities for improvement, validate and prioritise technical stories. Implemented CI/CD, monitoring (ELK), and improved code quality (SonarQube).
Senior PHP Developer (Contractor) at UEFA
July 1, 2018 - July 1, 2018Poll Games applications: Goal of the Week, Goal of the Season, Player of the Week, Player of the Match. Stack: PHP, JavaScript, MongoDB.
Senior Software Engineer at WorkDigital (dice.com)
June 1, 2017 - June 1, 2017Part of the Data platform, responsible for terabytes of search data indices (Elasticsearch, Solr). Refactored functionality and improved index performance; built REST APIs powering various systems; mentored teams on Elasticsearch; tested with PHPUnit.
Senior Software Engineer Backend at Liquid Healthcare
April 1, 2016 - April 1, 2016Microservices on Docker in AWS; services like beanstalkd, Redis, Elasticsearch, ejabberd; PHP Zend Framework 2 apps; frontend Backbone.js; collaborated with OSS/open-source projects.
Software Engineer at GSMA
April 1, 2014 - April 1, 2014Migrated from Windows/IIS/PHP to open-source stack (CentOS/Nginx/Postgres); contributed to modernization efforts and integration work.
Software Engineer at Tuenti
August 1, 2013 - August 1, 2013Worked on core site areas (Profile, Register, Settings); contributed to internal CMS and API integrations; developed server-side scripts for data population and analytics; maintained web site search index.
Parental leave at Personal Projects
January 1, 2023 - January 1, 2023Paternity leave and other passion projects.
Full stack – React & PHP & AWS (Contractor) at People’s Postcode Lottery
April 1, 2020 - April 1, 2020Upgraded Symfony version, modularised a monolith into React SPAs with separate CI/CD (Jenkins, AWS CDK, CodeBuild, CodePipeline); created Kibana dashboards and mentored the team on Elasticsearch.
Full stack – React & Node (Contractor) at Wipro (Lloyds Banking Group)
July 1, 2019 - July 1, 2019Supported pensions and retirement journey projects; focused on accessibility and mobile-first approach.
Parental leave
January 1, 2023 - January 1, 2023Parental leave and other passion projects.
Career break
December 1, 2013 - December 1, 2013Travelled to the USA, Germany and Morocco prior to relocation to the UK.
Education
Associate Degree in Computer Science at Instituto Politécnico Jesús Marín
September 1, 2003 - June 1, 2005Qualifications
Industry Experience
Software & Internet, Media & Entertainment, Government, Education, Professional Services, Financial Services
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
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