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I'm Jack Ivanisevic, a Senior Full-Stack Engineer with 12+ years of experience designing, building, and optimizing production software across frontend, backend, database, and integration layers. I excel at quickly understanding existing codebases, solving complex technical problems, and collaborating with business stakeholders to deliver reliable, scalable software. I specialize in API integrations, workflow automation, authentication, RBAC, database design, and AI-powered solutions including LLM integrations and event-driven workflows. I thrive in cross-functional teams, enjoy turning ambitious ideas into practical, maintainable systems, and continuously drive improvements in reliability and performance.…I'm Jack Ivanisevic, a Senior Full-Stack Engineer with 12+ years of experience designing, building, and optimizing production software across frontend, backend, database, and integration layers. I excel at quickly understanding existing codebases, solving complex technical problems, and collaborating with business stakeholders to deliver reliable, scalable software. I specialize in API integrations, workflow automation, authentication, RBAC, database design, and AI-powered solutions including LLM integrations and event-driven workflows. I thrive in cross-functional teams, enjoy turning ambitious ideas into practical, maintainable systems, and continuously drive improvements in reliability and performance.

Jack Ivanisevic

Full Stack Developer, Web Developer, Programmer, +7

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I'm Jack Ivanisevic, a Senior Full-Stack Engineer with 12+ years of experience designing, building, and optimizing production software across frontend, backend, database, and integration layers. I excel at quickly understanding existing codebases, solving complex technical problems, and collaborating with business stakeholders to deliver reliable, scalable software. I specialize in API integrations, workflow automation, authentication, RBAC, database design, and AI-powered solutions including LLM integrations and event-driven workflows. I thrive in cross-functional teams, enjoy turning ambitious ideas into practical, maintainable systems, and continuously drive improvements in reliability and performance.…I'm Jack Ivanisevic, a Senior Full-Stack Engineer with 12+ years of experience designing, building, and optimizing production software across frontend, backend, database, and integration layers. I excel at quickly understanding existing codebases, solving complex technical problems, and collaborating with business stakeholders to deliver reliable, scalable software. I specialize in API integrations, workflow automation, authentication, RBAC, database design, and AI-powered solutions including LLM integrations and event-driven workflows. I thrive in cross-functional teams, enjoy turning ambitious ideas into practical, maintainable systems, and continuously drive improvements in reliability and performance.

Available to hire

I’m Jack Ivanisevic, a Senior Full-Stack Engineer with 12+ years of experience designing, building, and optimizing production software across frontend, backend, database, and integration layers. I excel at quickly understanding existing codebases, solving complex technical problems, and collaborating with business stakeholders to deliver reliable, scalable software.

I specialize in API integrations, workflow automation, authentication, RBAC, database design, and AI-powered solutions including LLM integrations and event-driven workflows. I thrive in cross-functional teams, enjoy turning ambitious ideas into practical, maintainable systems, and continuously drive improvements in reliability and performance.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Croatian

Advanced

Work Experience

IT Project Manager at Respond Solutions

January 1, 2022 - January 1, 2022

Led technical upgrade projects by coordinating with consultants and developers for integrations. Developed project roadmaps with defined objectives, timelines and milestones, allocated resources, and prepared budgets. Designed, documented and executed system upgrades and patch management. Proposed and implemented system enhancements to improve performance and reliability of the storage environment. Created robust custom web applications to manage assets and fostered Agile collaboration to streamline project delivery.

Director of IT Systems at Premergency Inc.

January 1, 2022 - January 1, 2022

Oversaw operations and provided corrective feedback to achieve daily and long-term goals. Streamlined office workflows and administrative processes. Established departmental performance goals and provided feedback for nonperforming areas. Optimized operational processes using analytics to address client-specific metrics. Performed PHP development and led a team of 7 developers. Created 2 custom Moodle modules and established a culture of continuous improvement through open communication and empowerment.

Digital Marketing & Technology Consultant at Contract — Canada

January 1, 2016 - Present

Developed backend automation systems and integration workflows to reduce manual effort and improve operational efficiency. Built scalable API integrations between internal applications and third-party platforms. Designed database structures, data pipelines, and backend workflows supporting business-critical applications. Diagnosed and resolved complex integration, database, and application issues in production. Supported AI-assisted automation initiatives and backend workflow improvements across multiple client projects.

Website Development & Digital Platforms (Contract / Freelance) at Independent — Canada (Remote)

January 1, 2016 - Present

Designed and developed modern, responsive websites for small businesses and community-focused platforms. Delivered full website builds under compressed timelines, including design, development, QA, and launch. Implemented secure authentication and login systems to gate user access to private content. Built admin-friendly CMS interfaces enabling clients and partners to manage content independently. Translated business requirements into UI flows and intuitive user journeys. Ensured cross-browser compatibility, mobile responsiveness, and performance optimization. Produced documentation and walkthroughs for ongoing site management and maintenance.

Marketing Operations, Website & Analytics Support at Independent / Contract

January 1, 2016 - Present

Managed ongoing updates and content changes across marketing websites and landing pages using CMS platforms. Coordinated requests from marketing, creative, and technical teams to ensure timely updates. Performed routine site maintenance including content QA, link validation, image updates, and basic troubleshooting. Ensured content aligned with brand standards, regulatory considerations, and performance best practices. Collaborated with developers and designers to implement new features, landing pages, and layout updates. Monitored site performance and user behavior with GA4, flagging issues and optimization opportunities. Assisted with SEO fundamentals including metadata review and page structure checks. Supported email and digital campaigns with template QA and HTML review as needed.

Project Manager/Lead Developer at Think Forward Technologies Inc.

May 1, 2013 - October 29, 2025

Managed projects from conception to delivery, ensuring deadlines and quality while maintaining safe work practices. Initiated and supervised projects, controlled costs, and monitored performance. Served as system administrator for four servers supporting web deployments. Led custom web and software development, and collaborated with senior management to align objectives with strategic initiatives. Mentored junior team members and integrated Moodle features to improve customer satisfaction. Monitored progress against established goals, adjusting schedules and resources as needed.

Full-Stack & Application Development at Independent / Contract

January 1, 2010 - January 1, 2016

Built and supported web applications involving user workflows, dashboards, and data-driven interfaces. Collaborated with designers and stakeholders to align UX with business goals. Maintained and enhanced existing applications with new features and improvements.

Digital Marketing Systems & Analytics Support at Independent / Contract

January 1, 2010 - January 1, 2016

Supported digital marketing and website operations through analytics, reporting, and tracking validation. Maintained dashboards and reports to support marketing and website performance decisions. Assisted with troubleshooting data integrity, tracking discrepancies, and reporting accuracy issues.

Director of IT Systems at Premergency Inc.

January 1, 2009 - January 1, 2022

Led development, maintenance, and optimization of enterprise business systems, web applications, databases, and supporting infrastructure. Managed full-stack application development, Linux servers, PostgreSQL/MySQL databases, and deployment environments. Designed and implemented workflow automation solutions to improve operational efficiency and reduce manual processes. Diagnosed and resolved complex production issues across applications, infrastructure, databases, and third-party integrations. Provided technical leadership, mentoring, and architectural guidance while supporting day-to-day business operations.

Senior Full-Stack Engineer & Systems Engineer at Freelance / Contract

January 1, 2003 - Present

Collaborated with founders and stakeholders to define technical requirements and deliver scalable software solutions. Designed and maintained full-stack applications using React, TypeScript, Node.js, PostgreSQL, and REST APIs. Diagnosed and resolved complex production issues across backend services, databases, integrations, and asynchronous workflows. Implemented secure API integrations and automated workflows connecting third-party platforms. Developed scalable backend services for reporting, onboarding, and operational processes. Implemented authentication, role-based access control, and secure backend functionality across multiple client environments. Integrated AI-powered features and LLM-assisted workflows to boost automation and efficiency. Quickly understood existing codebases and collaborated with cross-functional teams to deliver reliable, production-ready software.