Available to hire
I’m Svetoslav Kirov, a seasoned principal full-stack engineer with over 20 years of experience in web and mobile development. I specialize in React and React Native and have a proven track record of leading cross-functional teams, raising code standards, and designing scalable architectures.
I enjoy turning ideas into shipped products across fintech, e-commerce, and publishing, mentoring engineers along the way and driving continuous improvement. I thrive on building cohesive user experiences across web and mobile and guiding teams through the full SDLC with a focus on quality and collaboration.
Skills
Experience Level
Expert
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Language
Bulgarian
Fluent
English
Fluent
German
Fluent
Russian
Advanced
Work Experience
Senior Software Engineer, Team Lead at Phos Ltd
July 1, 2017 - May 31, 2021Led software development lifecycle, architecture and data flow for banking/financial projects; guided a 6-person team; delivered scalable web applications and maintained code quality.
Senior Software Engineer, Team Lead at Phos Ltd
June 1, 2021 - February 28, 2023Led banking-related software projects; architected system components, implemented fintech features, ensured compliance with industry regulations.
Principal Engineer, Team Lead at Phos Ltd
March 1, 2023 - February 28, 2025Led architecture and data flows for banking software; led a 5-person team; web portals and microservices; mobile apps; blockchain components.
Team Lead at GDM FX Europe LTD
July 1, 2013 - February 28, 2015Led a development team in Forex finance software; architecture design, DB design, and performance optimization.
Senior Web Developer at Goos Web Development LTD
July 1, 2012 - June 30, 2013Web development focus; architecture, DBs, and full-stack implementation using JavaScript, SQL, and server-side languages.
Principal Engineer, Team Lead
March 1, 2023 - February 28, 2025Led software engineering initiatives, defined architecture and best practices, guided multiple engineering teams, and oversaw development lifecycle for complex web and mobile applications.
Team Lead at BLUBITO AD
July 1, 2015 - June 30, 2017Led backend/frontend development, designed scalable web applications and data architectures.
System Administrator / Web Developer at Kontiko LTD
November 1, 2003 - October 31, 2005Web development and systems administration for clients; network and server management.
Team Lead at Digital Ltd
March 1, 2025 - February 1, 2026Led development of OSI Wallet, a secure Web3 wallet enabling Bitcoin and blockchain integrations; guided engineering teams to adhere to best practices and high-quality code standards; architected scalable fintech solutions ensuring crypto-to-transaction integrity and regulatory compliance; mentored junior developers and oversaw the full SDLC from requirements through deployment; built cross-platform mobile features with React Native for consistent UX across iOS and Android.
Principal Engineer & Team Lead at BankingOn Remote
March 1, 2023 - February 1, 2025Designed and led a React-first rebuild of customer and admin portals, introducing a query-driven server cache and standardized forms system; developed a shared component library documented in Storybook with interactive and accessibility tests; implemented type-safe APIs via code generation from OpenAPI, reducing runtime errors and improving developer experience; collaborated with Python/Flask teams on API design, versioning, and error envelopes; introduced observability with App Insights and performance budgets using route-level chunks and Suspense patterns; mentored over five engineers, instituting code review guidelines, CI quality gates, and release hygiene on Azure; prototyped AI features leveraging OpenAI, Anthropic and Gemini models to deliver streaming chat interfaces and tool-calling adapters; implemented new mobile banking features using React Native with a unified web/mobile codebase.
Senior Software Engineer & Team Lead at Phos LTD
June 1, 2021 - February 1, 2023Migrated a large legacy codebase to TypeScript and modern React, introducing a query for server cache and Zustand for local state; delivered merchant dashboards and internal admin tools with complex forms, inline validation, and optimistic updates; added end-to-end coverage via Cypress and standardized Storybook documentation, reducing regressions; coordinated with product and design teams to define UI patterns, empty states, and error boundaries; managed a team of five developers across full-stack, backend, and frontend; introduced React Native to mobile development process, architecting Android and iOS applications with shared business logic.
Senior Engineering Manager & Owner at Valteo Digital Ltd
July 1, 2017 - May 1, 2021Delivered React-based SPAs and Next.js sites for e-commerce, media, and admin tooling with SSR/SSG; designed and implemented design systems and component libraries documented in Storybook; set up CI/CD pipelines and infrastructure as code, coaching teams on testing strategies and performance; managed a team of eight developers across full-stack, backend, frontend, mobile, and QA; directed development of mobile apps with React Native for rapid cross-platform delivery; developed Molib, a cross-platform digital publishing platform; built a web-based CMS for Molib to manage digital content and interactive enrichments; integrated API strategies and Freischaltcode mechanisms to enable flexible data transfer with external systems and web shops; deployed Molib on a FINMA-certified Swiss data center with DRM and encrypted data transfer.
Team Lead at Blu bit o ADS Sofia, Bulgaria
March 1, 2015 - July 1, 2017Designed architectures and led development for e-commerce systems using JavaScript, C#, PHP, and Java; implemented React/Ionic mobile apps and services; led teams of 6–12 across backend, full-stack, mobile, and QA; built HappyShops — a multi-shop platform for a Swiss retailer, with plug-in architecture and multi-language support; integrated multiple online shops into a unified back end as the first multi-shop provider in Switzerland; enhanced the gift and experience marketplace with high-volume product catalogs, secure payments, and improved performance to support over 200,000 customers.
Senior Web Developer & Team Lead at Various Companies (GDM FX, GOOS Web Development, ELPROM TRADE MSK, etc.)
January 1, 2002 - January 1, 2015Held senior and lead roles across multiple companies, architecting and developing web and mobile solutions; designed SQL databases, optimized performance, and administered Linux-based servers; developed applications using JavaScript, PHP, C#, Java, Python and various frontend frameworks; managed teams ranging from 3 to 12 developers delivering projects across finance, e-commerce, and media sectors.
Education
Bachelor degree at Sofia University
September 1, 2005 - June 30, 2008Bachelor degree at Sofia University
September 1, 2002 - June 30, 2004Professional at National High School of Finance and Economics Sofia
September 1, 1996 - August 31, 2001Bachelor's degree in Information Technologies at SVU BIT Sofia
September 1, 2002 - June 1, 2004Bachelor's degree in Management and Economics at National High School of Finance and Economics, Sofia
September 1, 1996 - June 1, 2001Bachelor's Degree in Information Technology at SVU BITS Sofia, Bulgaria
September 1, 2005 - June 1, 2008Bachelor's Degree in Applied Mathematics at Sofia University Sofia, Bulgaria
September 1, 2003 - June 1, 2004Professional High School Diploma in Finance & Economics (Management & Economics) at National High School of Finance and Economics Sofia, Bulgaria
September 1, 1996 - August 1, 2001Qualifications
Zend PHP Certificate
January 11, 2030 - February 3, 2026JavaScript Certificate
January 11, 2030 - February 3, 2026Python Certificate
January 11, 2030 - February 3, 2026MySQL Certificate
January 11, 2030 - February 3, 2026Scrum Certificate
January 11, 2030 - February 3, 2026PHP Certification
January 11, 2030 - March 11, 2026JavaScript Certification
January 11, 2030 - March 11, 2026MySQL Certification
January 11, 2030 - March 11, 2026Scrum Certification
January 11, 2030 - March 11, 2026Zend PHP Certification
January 11, 2030 - March 11, 2026JavaScript Certification
January 11, 2030 - March 11, 2026Python Certification
January 11, 2030 - March 11, 2026MySQL Certification
January 11, 2030 - March 11, 2026Scrum Certification
January 11, 2030 - March 11, 2026Industry Experience
Software & Internet, Financial Services, Professional Services, Media & Entertainment, Education, Computers & Electronics, Retail
Skills
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Expert
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