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Hi there! I'm Ivan Lacković, a frontend-focused software engineer with 7+ years of experience building web apps with React and TypeScript, and a track record of performance-first architecture. I’ve led full-scale app rewrites, optimized CI/CD workflows, and built scalable design systems with component-driven approaches, balancing usability, scalability, and maintainability. Most recently I contributed to a custom invoicing platform at Deas DK, integrating Firebase and Google Cloud Document AI to automate document handling and data flows. Across roles at Celtra, Kantun Devs, and iOLAP I’ve delivered ecommerce platforms, CMS-driven apps, and multi-tenant frontends, mentoring junior developers and helping teams adopt better tooling and architecture practices. I’m excited to bring my experience to a collaborative team focused on building fast, reliable, and maintainable systems.…Hi there! I'm Ivan Lacković, a frontend-focused software engineer with 7+ years of experience building web apps with React and TypeScript, and a track record of performance-first architecture. I’ve led full-scale app rewrites, optimized CI/CD workflows, and built scalable design systems with component-driven approaches, balancing usability, scalability, and maintainability. Most recently I contributed to a custom invoicing platform at Deas DK, integrating Firebase and Google Cloud Document AI to automate document handling and data flows. Across roles at Celtra, Kantun Devs, and iOLAP I’ve delivered ecommerce platforms, CMS-driven apps, and multi-tenant frontends, mentoring junior developers and helping teams adopt better tooling and architecture practices. I’m excited to bring my experience to a collaborative team focused on building fast, reliable, and maintainable systems.

Ivan Lacković

Front-End Developer, Full Stack Developer, Web Developer, +3

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Hi there! I'm Ivan Lacković, a frontend-focused software engineer with 7+ years of experience building web apps with React and TypeScript, and a track record of performance-first architecture. I’ve led full-scale app rewrites, optimized CI/CD workflows, and built scalable design systems with component-driven approaches, balancing usability, scalability, and maintainability. Most recently I contributed to a custom invoicing platform at Deas DK, integrating Firebase and Google Cloud Document AI to automate document handling and data flows. Across roles at Celtra, Kantun Devs, and iOLAP I’ve delivered ecommerce platforms, CMS-driven apps, and multi-tenant frontends, mentoring junior developers and helping teams adopt better tooling and architecture practices. I’m excited to bring my experience to a collaborative team focused on building fast, reliable, and maintainable systems.…Hi there! I'm Ivan Lacković, a frontend-focused software engineer with 7+ years of experience building web apps with React and TypeScript, and a track record of performance-first architecture. I’ve led full-scale app rewrites, optimized CI/CD workflows, and built scalable design systems with component-driven approaches, balancing usability, scalability, and maintainability. Most recently I contributed to a custom invoicing platform at Deas DK, integrating Firebase and Google Cloud Document AI to automate document handling and data flows. Across roles at Celtra, Kantun Devs, and iOLAP I’ve delivered ecommerce platforms, CMS-driven apps, and multi-tenant frontends, mentoring junior developers and helping teams adopt better tooling and architecture practices. I’m excited to bring my experience to a collaborative team focused on building fast, reliable, and maintainable systems.

Available to hire

Hi there! I’m Ivan Lacković, a frontend-focused software engineer with 7+ years of experience building web apps with React and TypeScript, and a track record of performance-first architecture. I’ve led full-scale app rewrites, optimized CI/CD workflows, and built scalable design systems with component-driven approaches, balancing usability, scalability, and maintainability.

Most recently I contributed to a custom invoicing platform at Deas DK, integrating Firebase and Google Cloud Document AI to automate document handling and data flows. Across roles at Celtra, Kantun Devs, and iOLAP I’ve delivered ecommerce platforms, CMS-driven apps, and multi-tenant frontends, mentoring junior developers and helping teams adopt better tooling and architecture practices. I’m excited to bring my experience to a collaborative team focused on building fast, reliable, and maintainable systems.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Croatian

Advanced

Work Experience

Senior Software Engineer

August 1, 2021 - September 5, 2025

Remote/on-site role focusing on modernizing a legacy frontend and backend stack. Migrated a CoffeeScript frontend to Vue 3, established ESLint-based coding standards, and set up a component library to unify frontend development. Rewrote a back-office project with React, MySQL and Heroku, and upgraded MySQL from 5.7 to 8+ to improve end-of-life maintenance and overall stability. Implemented code quality improvements and kept teams aligned through documentation and reviews.

Lead

September 1, 2022 - September 5, 2025

Led e-commerce site rewrite from the ground up using Next.js (React), Node.js, Strapi CMS, AWS, and Vercel. Built templated frontend components derived from CMS data; created a scalable architecture with a CI/CD pipeline and migrated hosting from AWS to Vercel to reduce costs. Achieved a 391% increase in online orders and a 32% rise in average order value; delivered new order flow and loyalty features with payment gateway integration; significant SEO/performance improvements.

Senior Software Engineer

August 1, 2022 - Present

Monorepo multi-tenant initiative; Next.js frontends templated from CMS data; extended Strapi CMS integration and performed data migrations to PostgreSQL. Modernised frontend architecture by extending MVC patterns, deployed on AWS infrastructure (EC2, S3, RDS) with PM2 and Nginx, and implemented scalable backend features in Node.js. Built dashboards for franchise stores and continued SEO/performance improvements; extended backend architecture with Node.js and AWS.

Senior Software Engineer

August 1, 2022 - Present

Remote-first role focusing on frontend and backend architecture across a monorepo multi-tenant system. Led an initiative for a monolithic frontend migration and modernization, migrating from Vue 2 to Vue 3, and established coding standards. Implemented ESLint rules, mentored junior engineers, and built a reusable component library with Storybook to improve code quality and UI consistency. Drove end-to-end improvements, performance, SEO, and collaboration across stakeholders, using React, Next.js, Vue, Node.js, Strapi CMS, PostgreSQL, MySQL, AWS, and Vercel.

Senior Software Engineer

September 30, 2022 - September 5, 2025

Hybrid frontend/backend role focused on re-building an e-commerce site from the ground up using Next.js (React), Node.js, Strapi CMS, AWS, and Vercel. Led frontend architecture, migrated data models to PostgreSQL/MySQL, and implemented SEO/performance improvements. Built CMS integrations for frontend projects, designed scalable data models, and ensured robust CI/CD pipelines. Mentored junior engineers, established coding standards, and extended Storybook-driven component libraries for a consistent UI across products.

Senior Software Engineer

July 31, 2025 - September 5, 2025

Contract remote engagement delivering a back-office invoicing solution: Next.js (React) front-end with Firebase, D365 integration for invoicing management and data syncing; automated invoice processing and data interpretation using Google Cloud Document AI; streaming workflows for invoice creation and email-based data extraction. Redesigned and optimized a marketing website using the latest Next.js version, improving performance, SEO, and multilingual support. 7+ years of experience building robust, scalable front-end and back-end systems across e-commerce, SaaS, and enterprise environments.