Viktor Kalajo
Senior Full-Stack Software Engineer, Stockholm
viktor.kalajo@gmail.com
With 12+ years of professional web development experience, I create products that deliver real value to users and stakeholders. I thrive in end-to-end involvement, from defining business goals and user needs to shaping UX, architecture, and writing the code.
Summary of Qualifications
- Over 12 years of full-stack web development experience, specializing in TypeScript, React, and Node.js.
- Proven track record in architecting and delivering large-scale applications, successfully leading projects from proof of concept to production.
- Expertise in data storage and processing solutions, including PostgreSQL, ElasticSearch, Kafka and Redis.
- Proficient in CI/CD implementation, with a focus on automated testing for robust deployment pipelines.
Highlighted projects
SVT AstridFull-stack, Q1 2020 - present
As a core developer of Astrid, the publishing platform for SVT News and Sports, I played a key role in shaping its architecture and driving it from proof of concept to production. My involvement spanned the entire development lifecycle—from defining goals to collaborating on UX and writing code.
Astrid powers one of Sweden's largest news sites, svt.se, as well as the SVT Nyheter and SVT Sport apps. The platform has around 400 editors, reaching millions of unique weekly readers with articles and feeds.
One of the major technical challenges was enabling real-time collaboration among editors on articles and feeds. We solved this by implementing an event-driven architecture, which supports seamless and concurrent editing.
Working with a highly autonomous team of eight, we built a system that received wide praise throughout the organization for its reliability and usability.
SVT DirektcenterFull-stack, Q1 2019 - Q1 2020
Direktcenter is a versatile CMS designed for creating real-time news streams, chats, and more. It’s widely used within SVT for both News and Play content, supporting live, interactive features that enhance viewer engagement.
Additionally, Direktcenter serves as the backup CMS for SVT Nyheter, ensuring news delivery when the primary system is down. Built for scale, it can support up to one million concurrent readers, delivering live updates within milliseconds.
SVT SportFront-end developer, Q3 2014 - Q1 2019 (periodically)
SVT site for sport news, svt.se/sport. Isomorphic/universal SPA built using React, Node and Express. High demands on performance and accessibility with ~500k unique visitors per week.
ThriveSole full-stack-developer, Q1 2016 - Q3 2018
Survey tool. Single page application built using React, Redux, Node, MongoDB, Heroku and CloudFlare. I was responsible for the entire tech stack in this project.
Proffessional Experience
Viktor Kalajo ABFreelancing developer, Q2 2018 - Current
Most of my second round of freelancing has been on different projects in SVT. They are described in detail under "Highlighted projects".
CreunaSenior interface developer, Q2 2014 - Q2 2018
At Creuna I had the opportunity to work with well-known companies such as Spotify, MTG, Akademibokhandeln and SVT. My role was primarily as a front-end developer with focus on JavaScript but I also worked on the back-end, especially in projects using Node and Python plus Django.
Individual companyFreelancing developer, Q2 2010 - Q2 2018
Delivered multiple web applications and websites as the sole developer, including a travel agency website with a booking system, a survey tool, a time reporting system, an e-commerce site for dress-up clothing, and several small-business WordPress websites. Additionally, I conducted lectures on web analytics. I ran these freelance projects in parallell with my university studies and my employment at Creuna.
SwerobRobotics technician, Q2 2007 - Q4 2008
Programming and service of industrial (ABB) robots. Part time during High school.
Education
KTH Royal Institute of TechnologyQ3 2008 - Q4 2013
Master of Science in Software Design and Industrial Economics and Management at KTH Royal Institute of Technology.