Karlo B.

Fullstack Developer

Karlo is a skilled software engineer with a focus on Full-stack development and over a decade of commercial experience.

While his expertise primarily lies in back-end development, he also has significant experience architecting front-end and mobile solutions. His roles have included Solution Architect, DevOps Engineer, and Software Architect, leading major projects for international companies across industries such as gaming, government digital services, public transport, e-commerce, AI, and blockchain.

In addition to his professional work, Karlo has achieved notable success as an indie game developer, with his games amassing over 5 million downloads. He has leadership experience managing a team of five and holds an MSc in Software Engineering, showcasing both his technical expertise and ability to guide teams effectively.

Main expertise

  • AWS CDK
    AWS CDK 2 years
  • AWS Lambda
    AWS Lambda 1 years
  • AWS S3
    AWS S3 1 years

Other skills

  • Python
    Python 2 years
  • Blazor
    Blazor 1 years
  • Blockchain
    Blockchain 1 years
Karlo

Karlo B.

Croatia

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Selected experience

Employment

  • Software Architect

    NextLevel Dev - 4 months

    Developed a comprehensive mobile and web application for lawyers and judges to manage legal cases and court notices. Seamlessly integrated with government digital services while ensuring security and data protection.

    • Integrated advanced AI capabilities by training custom models, utilizing vector databases for efficient RAG and LangChain to streamline AI workflows
    • Created a data pipeline processing 5 million court notices and normalizing the data for embedding using Python
    • Implemented a custom backend using .NET and MartenDB
    • Implemented a mobile client using React Native and Expo for Android and iOS
    • Implemented a web client using Next.js
    • Integrated with government digital services

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • Docker Docker
    • PostgreSQL PostgreSQL
    • TypeScript TypeScript
    • React Native React Native
    • Python Python
    • Next.js Next.js
    • .NET Core .NET Core
    • Machine Learning Machine Learning
    • Expo Expo
    • Solution Architecture
    • OpenAI API OpenAI API
    • LangChain LangChain
    • Large Language Models (LLM) Large Language Models (LLM)
  • Software Architect / Full-stack Web Developer

    TrustNXT GmbH - 1 year 4 months

    • Built a comprehensive ecosystem for image signing, verification, and management using C2PA standard
    • Solely architected and implemented both backend and frontend systems, ensuring full AWS serverless deployment (Lambda, DynamoDB, S3, CloudFront, SQS, SNS, SST)
    • Engineered SDK for iOS and Android featuring advanced protect and inspect methods, complete with detailed Fumadocs documentation for streamlined integration
    • Integrated private Certificate Authority for ephemeral certificate generation and management
    • Created public API for third-party verification
    • Contributed to the open-sourced TypeScript SDK for C2PA

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • React.js React.js
    • AWS AWS
    • TypeScript TypeScript
    • Node.js Node.js
    • GraphQL GraphQL
    • Microservices
    • AWS SQS AWS SQS
    • AWS Lambda AWS Lambda
    • AWS S3 AWS S3
    • Android Android
    • iOS iOS
    • Next.js Next.js
    • Tailwind Tailwind
    • DevOps DevOps
    • DynamoDB DynamoDB
    • Git Git
    • AWS CDK AWS CDK
    • NoSQL
    • Solution Architecture
    • AWS Cognito AWS Cognito
  • Solution Architect / DevOps Engineer

    JobBoost B.V. - 11 months

    • Designed and oversaw the migration of a monolithic system to the cloud using a microservices architecture.
    • Developed and implemented a strategic roadmap for the migration process, ensuring minimal disruption to ongoing operations.
    • Collaborated closely with cross-functional teams to define and prioritize microservices, optimizing for system performance and scalability.
    • Architected and implemented DevOps practices to streamline deployments and improve system reliability.
    • Conducted assessments and evaluations to identify areas for improvement in the migration strategy and microservices architecture.
    • Established and enforced best practices for code quality, security, and scalability within the microservices ecosystem.
    • Provided technical guidance and mentorship to the development team, fostering a culture of continuous learning and innovation.
    • Managed and optimized AWS cloud infrastructure to meet performance, security, and scalability requirements.
    • Implemented CI/CD pipelines using GitHub Actions to automate the build, test, and deployment of microservices.

    Technologies:

    • Technologies:
    • PHP PHP
    • Laravel Laravel
    • JavaScript JavaScript
    • Vue.js Vue.js
    • Docker Docker
    • AWS AWS
    • ElasticSearch ElasticSearch
    • Redis Redis
    • TypeScript TypeScript
    • Node.js Node.js
    • Microservices
    • AWS SQS AWS SQS
    • Kubernetes Kubernetes
    • AWS Lambda AWS Lambda
    • AWS S3 AWS S3
    • Terraform Terraform
    • DevOps DevOps
    • Data Engineering
    • DynamoDB DynamoDB
    • Linux Linux
    • Git Git
    • Unix Unix
    • Machine Learning Machine Learning
    • AWS CDK AWS CDK
    • NoSQL
    • Solution Architecture
    • Prompt Engineering
    • LangChain LangChain
    • AWS ECS AWS ECS
    • Large Language Models (LLM) Large Language Models (LLM)
  • Software Architect / Full-stack Developer

    Peoples Place Community Partnerships - 5 months

    • Designed and implemented a scalable, multi-tenant back-office system for Community21 using Azure Cloud, .NET 7, and Next.js
    • Integrated Azure AD B2C to ensure secure and seamless user authentication and authorization within the system
    • Applied Clean Architecture principles, leveraging Domain-Driven Design (DDD) and Command Query Responsibility Segregation (CQRS) patterns to establish a modular and maintainable architecture
    • Created a data-driven solution utilizing Azure SQL Database and Azure Blob Storage to manage participant information and analyze program performance efficiently
    • Ensured the system's compliance with industry standards and data security protocols, prioritizing the privacy and confidentiality of participant information
  • Software Architect / Full-stack Web Developer

    Peoples Place Community Partnerships - 5 months

    • Designed and implemented a scalable, multi-tenant back-office system for Community21 using Azure Cloud, .NET 7, and Next.js
    • Integrated Azure AD B2C to ensure secure and seamless user authentication and authorization within the system
    • Applied Clean Architecture principles, leveraging Domain-Driven Design (DDD) and Command Query Responsibility Segregation (CQRS) patterns to establish a modular and maintainable architecture
    • Created a data-driven solution utilizing Azure SQL Database and Azure Blob Storage to manage participant information and analyze program performance efficiently
    • Collaborated closely with stakeholders to understand project requirements and ensure alignment with the goals of supporting disadvantaged young people and addressing social issues
    • Led the development efforts as a software architect, overseeing the technical aspects of the project and ensuring adherence to best practices
    • Conducted regular assessments and optimizations to enhance system robustness, scalability, and performance
    • Ensured the system's compliance with industry standards and data security protocols, prioritizing the privacy and confidentiality of participant information

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • React.js React.js
    • TypeScript TypeScript
    • C# C#
    • SQL SQL
    • Azure Azure
    • .NET .NET
    • Azure Blob storage Azure Blob storage
    • Next.js Next.js
    • .NET Core .NET Core
    • DDD
    • Git Git
    • Azure Cloud Azure Cloud
    • Solution Architecture
  • Fullstack Developer

    Kimeru BV - 1 year

    • Ensured seamless integration and functionality of the system components
    • Conducted troubleshooting and debugging of issues within the system
    • Ensured code quality through rigorous testing and code reviews
    • Managed and monitored system deployments using Docker, Traefik, and Portainer
    • Utilized RabbitMQ for efficient message queuing and processing
    • Implemented and maintained background job processing using Hangfire
    • Engaged in version control and continuous integration/continuous deployment (CI/CD) using GitLab pipeline
  • Fullstack Engineer

    Kimeru BV - 1 year

    • Ensured seamless integration and functionality of the system components
    • Conducted troubleshooting and debugging of issues within the system
    • Ensured code quality through rigorous testing and code reviews
    • Managed and monitored system deployments using Docker, Traefik, and Portainer
    • Utilized RabbitMQ for efficient message queuing and processing
    • Implemented and maintained background job processing using Hangfire
    • Engaged in version control and continuous integration/continuous deployment (CI/CD) using GitLab pipeline

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • Angular.js Angular.js
    • MongoDB MongoDB
    • Docker Docker
    • TypeScript TypeScript
    • MSSQL MSSQL
    • C# C#
    • .NET .NET
    • ASP.NET ASP.NET
    • .NET Core .NET Core
    • DevOps DevOps
    • Angular Angular
    • Linux Linux
    • Git Git
    • RabbitMQ RabbitMQ
    • Hangfire Hangfire
    • Solution Architecture
    • Keycloak Keycloak
  • Principal Software Engineer

    Notch - 2 years

    Senior Software Engineer – Global Multi-Tenant D2C eCommerce Platform

    • Worked on a large-scale direct-to-consumer eCommerce platform supporting multi-vendor, multi-brand, and multi-market operations in both standardized and localized formats.
    • Centralized the configuration management of all microservices to enhance scalability and maintainability.
    • Identified and automated manual processes across the organization to increase operational efficiency.
    • Streamlined the deployment process for launching the system in new markets and rolling out new features.
    • Led integrations with Contentful (CMS) and Commercetools (headless commerce).
    • Implemented performance enhancements and optimizations to improve system speed and reliability.
    • Contributed to system design and architectural discussions, focusing on scalability and robustness.
    • Provided technical mentorship and guidance to the development team, promoting a collaborative and high-performing work environment.

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • React.js React.js
    • Docker Docker
    • PostgreSQL PostgreSQL
    • TypeScript TypeScript
    • GraphQL GraphQL
    • Microservices
    • Apache Kafka Apache Kafka
    • Kubernetes Kubernetes
    • C# C#
    • Azure Azure
    • .NET .NET
    • Entity Framework Entity Framework
    • Next.js Next.js
    • Tailwind Tailwind
    • Terraform Terraform
    • .NET Core .NET Core
    • DevOps DevOps
    • Linux Linux
    • Git Git
    • DataDog DataDog
    • Unix Unix
    • Enterprise Architect Enterprise Architect
    • Solution Architecture
    • Keycloak Keycloak
  • Senior Software Engineer

    King ICT - 3 years 9 months

    Senior Software Engineer – eTicketing Project for Public Transport

    • Served as a software architect and full-stack web and mobile developer on a public transport modernization project in Split, Croatia.
    • Developed mobile and web applications for trip planning and ticket purchasing.
    • Built real-time integrations with vehicle on-board units for live data communication.
    • Implemented a comprehensive back office and fleet management system.
    • Integrated multiple payment providers to support secure transactions.
    • Connected the system with Google Maps using the GTFS standard for route data.
    • Used Google Firebase for push notifications and app integrity checks.
    • Implemented ETA (Estimated Time of Arrival) calculations through Google APIs.
    • Managed authentication and authorization via Keycloak.
    • Utilized Figma for UX design and interface prototyping.

    Lead Developer – Electronic Toll Collection System

    • Led a cross-functional team of developers and designers.
    • Acted as the software architect and full-stack developer for modernizing Croatia's highway toll collection system.
    • Delivered web and mobile applications for account management and media top-ups.
    • Integrated payment gateways for seamless transactions.
    • Used Google Firebase to manage push notifications.
    • Developed a voucher distribution system and back-office portal.
    • Built integrations with ETC devices and smart card infrastructure.
    • Improved system performance through SQL query optimization and database indexing.

    Full-Stack Developer – Government Digital Services Platform

    • Contributed to a unified digital platform consolidating citizen services and form submissions.
    • Integrated with multiple payment providers for transactional features.
    • Enabled secure login via NIAS (eIDAS-compliant) authentication.
    • Integrated with Croatia’s e-Građani (e-Citizens) portal to streamline government-citizen interactions.

    Technologies:

    • Technologies:
    • JavaScript JavaScript
    • React.js React.js
    • PostgreSQL PostgreSQL
    • Redis Redis
    • TypeScript TypeScript
    • React Native React Native
    • Java Java
    • MSSQL MSSQL
    • Microservices
    • Jenkins Jenkins
    • Spring Spring
    • C# C#
    • SQL SQL
    • Oracle Oracle
    • Redux.js Redux.js
    • .NET .NET
    • Entity Framework Entity Framework
    • ASP.NET ASP.NET
    • Firebase Firebase
    • .NET Core .NET Core
    • DevOps DevOps
    • .NET framework .NET framework
    • Blazor Blazor
    • Linux Linux
    • WPF WPF
    • Git Git
    • RabbitMQ RabbitMQ
    • OAuth2 OAuth2
    • gRPC gRPC
    • SignalR SignalR
    • Google Maps Google Maps
    • Enterprise Architect Enterprise Architect
    • Mobile
    • Solution Architecture
    • Keycloak Keycloak
  • Unity Game Developer

    NextLevel Dev - 6 years 1 month

    Cross-platform game development implementing own ideas and solutions (PC, mobile and browser games)

    • Developed and published over 20 web, mobile and PC games with over 5 million players in total
    • Publishing on Google Play and App Store
    • Optimized performance, build size and quality to deliver better cross platform experience
    • Ads and InApp purchases integration
    • Apple Game Center and Google Play Games Services integration for leadboards and achievements
    • Implemented monetization strategies, analytics, and utilized reverse-engineering including code obfuscation

    Technologies:

    • Technologies:
    • MySQL MySQL
    • JavaScript JavaScript
    • React.js React.js
    • Docker Docker
    • PostgreSQL PostgreSQL
    • TypeScript TypeScript
    • Node.js Node.js
    • React Native React Native
    • Express.js Express.js
    • C# C#
    • .NET .NET
    • Android Android
    • iOS iOS
    • Next.js Next.js
    • Tailwind Tailwind
    • Firebase Firebase
    • .NET Core .NET Core
    • Nest.js Nest.js
    • DevOps DevOps
    • Data Engineering
    • Unity Unity
    • Git Git
    • Unix Unix
    • Mobile
    • HTML / CSS
    • Three.js Three.js
    • NoSQL
    • Solution Architecture
    • Solidity Solidity
    • Blockchain Blockchain
    • Supabase Supabase

Education

  • MSc.Software Engineering

    Faculty of Electrical Engineering and Computing, University of Zagreb · 2018 - 2020

  • BSc.Computing

    Faculty of Electrical Engineering and Computing, University of Zagreb · 2015 - 2018

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