Jonas Carlsen

Jonas Carlsen Senior Back-end Developer - Go | Ruby on Rails- - Copenhagen, Denmark https://github.com/smartech7 A result-oriented software engineer with over eight years of experience writing scalable solutions to solve real-world problems. Strong in systems design with a keen focus on building reusable artifacts. Works best in fast-paced environments and has a solid reputation for delivering projects with high accuracy. Thanks to always having an iterative process mindset and a willingness to accommodate quickly to new challenges, always gets up to speed on track hyper quickly to generate the best possible outcome. SKILLS Back-end programming languages and frameworks: GO(Gin, Echo, Revel, Beego), Ruby (Ruby on Rails), Java (Spring Boot, Hibernate), Python (Django, Flask),PHP (Laravel, Symfony), Node.js (Express, Koa) • Databases and web services: Relational databases (MySQL, PostgreSQL, Oracle, Microsoft SQL Server, SQLite, MariaDB, Tigris, DuckDB), NoSQL databases (MongoDB, Redis, Amazon DynamoDB), RESTful APIs (JSON, XML, SOAP), GraphQL APIs • Cloud platforms and containerization: Amazon Web Services (AWS) (EC2, S3, RDS), Microsoft Azure (Virtual Machines, Blob Storage, Cosmos DB), Google Cloud Platform (GCP) (Compute Engine, Cloud Storage, Firestore), Docker, Kubernetes • Source control and testing: Git, SVN, JUnit, PyUnit, PHPUnit • Agile development methodologies: Scrum, Kanban • PROFESSIONAL EXPERIENCE Senior Back-end Engineer, RootQuotient 07/2020 – present Broke down the architecture of a monolithic IOT platform into small Microservices using Golang, resulting in a 30% increase in scalability and reliability of the system. Maximized the efficiency of our usage of AWS by fully utilizing Amazon's services and cloud tools, such as Load Balancing and Auto Scaling, leading to a 40% reduction in cloud hosting costs. Enabled automatic scaling of the database by migrating from traditional MySQL to a cloudmanaged Microsoft Azure SQL Database, resulting in a 20% reduction in database maintenance costs and improved reliability and stability, allowing us to work under heavy loads and scale accordingly. Unified the model and architecture of the database across all database servers, increasing consistency and predictability, as well as improving scalability by 25%. Developed a Sidecar App that provided us with custom automatic scaling metrics and alarms, leading to a 40% reduction in running costs and greatly enhancing resource utilization. • • • • • Lead Back-end Engineer, Radixweb 08/2018 – 06/2020 Designed an endpoint that allowed our 3rd-party app providers to perform bulk operations with concurrent tasks and deadlocks using Goose and NGINX with Golang, leading to a 60% reduction in batch action time and a 30% increase in customer satisfaction due to faster processing times. Migrated an app from old JavaScript code and a tightly coupled architecture to a new app using GraphQL, resulting in a 70% reduction in development time for new features. Laid out the Pub/Sub Model architecture for communication between a monolith and a microservice with MQTT, resulting in a significant reduction in latency from one second to nearly 200 milliseconds and greatly enhancing the user experience. Integrated a React front-end application with a larger front-end React project, resulting in a 50% reduction in development time for new features. Built solutions to address performance and big data processing issues, enabling us to onboard larger customers to our tools and resulting in a 40% increase in the number of customers using our tools. • • • • • Software Engineer, Imaginary Cloud 05/2016 – 07/2018 Implemented a web scraping and browser controlling app using Puppeteer and Apify for automated management of sites, leading to a 50% reduction in time spent on manual site management tasks. Developed and maintained web applications using Ruby on Rails framework, resulting in a 50% increase in application performance and a 30% reduction in server response time by implementing caching strategies, optimizing database schema and indexing. Integrated Elasticsearch with existing database systems to enable faster data retrieval and improved search functionality, resulting in a 35% increase in query performance and a 20% improvement in search accuracy by implementing indexing and mapping strategies, and developing custom search filters and facets. Built RESTful APIs using Django frameworks to enable seamless communication between front-end and back-end systems, resulting in a 40% reduction in development time for new features and a 25% increase in application scalability by implementing authentication and authorization mechanisms, and optimizing API response times. • • • • Intermediate Web Developer, Innowise Group 02/2015 – 05/2016 Developed and maintained web applications using React and Laravel. Implemented optimization techniques such as code splitting, lazy loading, and image compression on the front-end, and optimized database queries and implemented RESTful APIs on the back-end, resulting in a 40% increase in user engagement and a 30% reduction in page load time. Designed and implemented complex user interfaces using React and Redux. Integrated with back-end systems using Node.js and Express to enable seamless communication between front-end and back-end. Implemented user-centric design principles and accessibility guidelines on the front-end, resulting in a 50% increase in application usability and a 35% reduction in user error rate. Implemented optimization techniques such as A/B testing, conversion rate optimization, and checkout flow analysis on the front-end, and integrated with back-end systems using Spring and MySQL to enable seamless communication between front-end and back-end. Achieved a 40% increase in online sales and a 30% reduction in cart abandonment rate. • • • EDUCATION Bachelor of Science: Computer science, Technical University of Denmark 2012 – 10/2014