Hi there! I'm Karl Olofsson, a versatile full-stack web developer focused on Java, React and SQL. I can shift focus easily when needed and I enjoy mentoring colleagues. I'm experienced across frontend and backend, leading API development, coordinating with front-end and data teams, and continuously improving testing, deployments, and processes. I'm passionate about building scalable, user-friendly software and fostering collaborative teams through Scrum and Kanban practices.

Karl Olofsson

Hi there! I'm Karl Olofsson, a versatile full-stack web developer focused on Java, React and SQL. I can shift focus easily when needed and I enjoy mentoring colleagues. I'm experienced across frontend and backend, leading API development, coordinating with front-end and data teams, and continuously improving testing, deployments, and processes. I'm passionate about building scalable, user-friendly software and fostering collaborative teams through Scrum and Kanban practices.

Available to hire

Hi there! I’m Karl Olofsson, a versatile full-stack web developer focused on Java, React and SQL. I can shift focus easily when needed and I enjoy mentoring colleagues.

I’m experienced across frontend and backend, leading API development, coordinating with front-end and data teams, and continuously improving testing, deployments, and processes. I’m passionate about building scalable, user-friendly software and fostering collaborative teams through Scrum and Kanban practices.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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Language

Swedish
Fluent
English
Advanced
Norwegian
Advanced

Work Experience

Team Lead / Supervisor (substituting) at XXL Sport & Vildmark Service Shop
March 1, 2025 - August 1, 2025
Responsible for service of bicycles, logistics and management of four mechanics; improved metrics and daily work efficiency by aligning tasks with team strengths and interests; enforced routines to increase quality and efficiency; contributed to a globally recognized XXL service shop and achieved 26% YoY sales growth.
Team Lead / Supervisor (substituting) at XL Sport & Vildmark Service Shop
March 1, 2025 - August 1, 2025
Responsible for service of bicycles, logistics and 4 mechanics. Increased performance of all metrics. Got to know everyone in order to optimize daily work according to their strengths and interests. Enforced and improved existing routines to increase quality and efficiency.
Backend Developer (in-house)
November 1, 2022 - August 1, 2024
Led API development for a new version of a central product component; coordinated with frontend and data teams; investigated and resolved an old bug via regression acceptance testing of an email feature after a simple SDK upgrade; contributed to cross-team effort to create a multi-step asynchronous system for matching customer data with internal data; worked with Scrum and Kanban; stack included Java, REST, Git, AWS Lambda, DynamoDB (NoSQL), Vue/Vuex, Node.
Back End Developer (in-house) at XL Sport & Vildmark
November 1, 2022 - August 1, 2024
Full stack team: Lead on API development for the new version of a central part of the product. Coordination with frontend and data teams as well as testing. Investigated and solved an old bug with regression acceptance testing of an email feature after a simple SDK upgrade. Contributed to cross-team effort to create a multi-step synchronous system for matching customer data with internal data. Led the MVP based on a PoC.
Full Stack Developer (in-house) at XL Sport & Vildmark
April 1, 2022 - October 1, 2022
Web development with Vue and AWS serverless. Built internal UI component library based on Figma. Reused existing SQL for business logic and built new APIs on top. Mentored junior colleagues. Team used Kanban.
Full Stack Developer (in-house)
March 1, 2021 - April 1, 2022
Feature lead during product redesign with MVC architecture for Azure; implemented parts of the product over several months to meet hard deadlines; built an internal UI component library based on Figma; reused existing SQL for business logic while creating new views and APIs; mentored junior colleagues; worked with Vue, AWS Lambda, DynamoDB, REST, Node and .NET Core; Kanban.
Full Stack Developer (in-house) at XL Sport & Vildmark
March 1, 2021 - April 1, 2022
Web development with Vue and AWS serverless. Focus on quick delivery of new features. Close cooperation with UX designer. Dealt with some technical debts, enabled unit testing with Jest for frontend and got better at debugging and deployment. Kanban.
Systems Developer at Various clients / Kanban
September 1, 2019 - December 1, 2020
Systems development and integration assignments for various clients in different industries and technologies. Focus on maturing as a developer and consultant.
Trainee / Intern at Kanban
September 1, 2018 - August 1, 2019
Focused on gaining experience as a consultant. Got Java SE 8 / Spring Boot, React, Angular, Vue, REST.
Analyst
October 1, 2016 - March 1, 2018
Built an internal app with a Node backend; advised/webmaster for an e-commerce startup; worked within Scrum and Kanban; used Java EE 6/8, Spring, React/Redux, Node and REST.
Trainee
September 1, 2016 - October 1, 2016
Gained experience as a consultant across assignments; studied Java SE 8 / Spring Boot, React, Angular, Vue, REST; worked with Scrum and Kanban.

Education

Pedagogy A at Mid Sweden University
September 1, 2025 - January 1, 2026
AI: Artificial Intelligence A-Z at Udemy
June 1, 2018 - March 5, 2026
AI with Python and PyTorch at Udemy
June 1, 2018 - March 5, 2026
Pedagogy A (PE205G) at Mid Sweden University
September 1, 2025 - January 1, 2026
Bachelor's degree in Systems Sciences (minor in BA) at Luleå University of Technology
January 1, 2014 - January 1, 2016
Science & Technology High School, STEM with focus on Computer Science at Wargentin Gymnasium
January 1, 2002 - January 1, 2005

Qualifications

Professional Scrum Master I
November 1, 2019 - March 5, 2026
Java SE 8 OCA
June 1, 2019 - March 5, 2026
Java SE 8
January 11, 2030 - March 5, 2026
Professional Scrum Master I
November 1, 2019 - March 5, 2026
AI: Artificial Intelligence A-Z
June 1, 2018 - March 5, 2026
AI with Python and PyTorch
June 1, 2018 - March 5, 2026
Oracle Java 8 OCA
June 1, 2019 - March 5, 2026
Professional Scrum Master I
November 1, 2019 - March 5, 2026
Udemy: Artificial Intelligence A-Z
June 1, 2018 - March 5, 2026

Industry Experience

Software & Internet, Retail, Professional Services, Education, Media & Entertainment

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
See more

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