Available to hire
Hi, I’m Mario Liebenberg, a frontend-focused software engineer with 5+ years of experience building web and mobile apps using React, TypeScript, and GraphQL. I enjoy shaping frontend architecture, mentoring teams, and shipping across diverse industries.
I’m expanding my backend skills in Spring Boot and Java to grow into full-stack development. I’m based in Johannesburg and open to remote roles in the EU/UK or relocation to join ambitious teams.
Skills
Experience Level
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
Language
English
Fluent
Afrikaans
Fluent
Work Experience
Software Engineer / Frontend Tech Lead at S-Squared Software
January 1, 2022 - PresentServe as the technical lead on several client projects, owning architectural decisions, tooling strategies, and tech stack evolution. Built and contributed to projects including a car sales/financing platform with an admin portal; a stock-tracking React Native app; a mobile network contract site rebuild; a custom component library; a 3D house configuration platform (Blender + Three.js); and a football management app with live push notifications. Day-to-day includes React, GraphQL, and TypeScript development with some backend involvement. Mentored developers and contributed to team delivery. Backend: Spring Boot, Node.js, Express, REST, GraphQL (Apollo & Relay). Other: Git, Agile, CI/CD.
Frontend Developer at League Digital
December 31, 2021 - September 19, 2025Worked on DSTV and Multichoice websites, converting wireframes to HTML, SCSS, JavaScript, React, and Twig. Integrated with Umbraco CMS, displaying dynamic content via Razor views (C#). Contributed to R&D in tools like Storybook.js, Three.js, and GSAP.
Frontend Developer at IMX Software
December 31, 2021 - September 19, 2025Built a web app for bank tellers to order and track foreign currency, supporting localisation and PDF report generation. Tech: React, TypeScript, Redux, Ant Design.
Developer at Ozra Media
December 31, 2022 - September 19, 2025Led frontend development of custom websites and applications for clients. Oversaw project design, brand direction, and client communication while mentoring junior devs. Built sites in WordPress, Gatsby.js, and React, with backend work in PHP and custom JS.
UX / Systems Analyst at DMM
December 31, 2019 - September 19, 2025Shifted from systems documentation into UI/UX improvements and supplier liaison for digital projects, while finishing degree and afterwards.
Software Engineer / Frontend Tech Lead at S-Squared Software
January 1, 2022 - PresentLead frontend architecture, tooling strategies, and tech stack evolution across client projects; built and contributed to a car sales/financing platform with an admin portal, a stock-tracking React Native app, a mobile network contract site rebuild, a custom component library, a 3D house configuration platform (Blender + Three.js), and a football management app with live push notifications. Daily work focused on React, GraphQL, and TypeScript with some backend involvement; mentored developers and contributed to team delivery (Spring Boot/Node.js/Express/REST/GraphQL).
Frontend Developer at League Digital
January 1, 2021 - September 19, 2025Worked on DSTV and Multichoice websites, converting wireframes to HTML, SCSS, JavaScript, React, and Twig. Integrated with Umbraco CMS and Razor views. Contributed to R&D in tools like Storybook.js, Three.js, and GSAP.
Frontend Developer at IMX Software
January 1, 2021 - September 19, 2025Built a web app for bank tellers to order and track foreign currency, supporting localisation and PDF report generation.
Developer at Ozra Media
January 1, 2022 - September 19, 2025Led frontend development of custom websites and applications for clients; oversaw project design, brand direction, and client communication while mentoring junior devs. Built sites in WordPress, Gatsby.js, and React, with backend work in PHP and custom JS.
Software Engineer / Frontend Tech Lead at S-Squared Software
January 1, 2022 - PresentLead frontend architecture and tooling decisions across client projects, including a car sales/financing platform, stock-tracking app, mobile network contract site rebuild, a custom component library, a 3D house configuration platform (Blender + Three.js), and a football management app with live push notifications. Day-to-day work focuses on React, GraphQL, and TypeScript development, mentoring team members, and collaboration with backend teams (Spring Boot, Node.js) within an Agile/CI/CD environment.
Developer at IMX Software
December 31, 2021 - September 19, 2025Built a web app for bank tellers to order and track foreign currency, supporting localisation and PDF report generation.
Frontend Developer at League Digital
December 31, 2021 - September 19, 2025Worked on DSTV and Multichoice websites, converting wireframes to HTML, SCSS, JavaScript, React, and Twig. Integrated with Umbraco CMS and Razor views; contributed to R&D in Storybook.js, Three.js, and GSAP.
Developer at Ozra Media
December 31, 2022 - September 19, 2025Led frontend development of custom websites and applications; oversaw project design, branding, and client communication while mentoring junior developers. Built sites in WordPress, Gatsby.js, and React, with backend work in PHP and custom JS.
Software Engineer / Frontend Tech Lead at S-Squared Software
January 1, 2022 - PresentTechnical lead on multiple client projects, responsible for architectural decisions, tooling strategies, and evolution of the tech stack. Hands-on development with React, GraphQL, and TypeScript; mentored developers and contributed to team delivery. Backend involvement with Spring Boot, Node.js/Express, REST, and GraphQL. Projects included a car sales/financing platform with an admin portal, a stock-tracking React Native app, a mobile network contract site rebuild, a custom component library, a 3D house configurator (Blender + Three.js), and a football management app with live push notifications.
Developer at IMX Software
January 1, 2021 - PresentBuilt a web app for bank tellers to order and track foreign currency, supporting localization and PDF report generation.
Frontend Developer at League Digital
January 1, 2021 - September 19, 2025Worked on DSTV and Multichoice websites, converting wireframes to HTML, SCSS, JavaScript, React, and Twig. Integrated with Umbraco CMS, displaying dynamic content via Razor views. Contributed to R&D in tools like Storybook.js, Three.js, and GSAP.
Developer at Ozra Media
January 1, 2022 - September 19, 2025Led frontend development of custom websites and applications for clients. Oversaw project design, brand direction, and client communication while mentoring junior devs. Built sites in WordPress, Gatsby.js, and React, with backend work in PHP and custom JS.
Database Developer at Global Investment Reporting
January 1, 2019 - September 19, 2025Built MySQL database and PHP/AJAX web app for monthly financial reporting.
UX / Systems Analyst at DMM
January 1, 2017 - September 19, 2025Shifted from systems documentation into UI/UX improvements and supplier liaison for digital projects, while finishing degree and afterwards.
Software Engineer / Frontend Tech Lead at S-Squared Software
January 1, 2022 - PresentLead frontend architecture and delivery across multiple client projects; mentored developers; built a custom component library; contributed to backend with Spring Boot, Node.js, Express, REST, GraphQL; day-to-day includes React, GraphQL, and TypeScript; based in Johannesburg; open to remote work or relocation (UK/EU preferred).
Developer at IMX Software
December 31, 2021 - September 19, 2025Built a web app for bank tellers to order and track foreign currency, supporting localization and PDF report generation. Tech: React, TypeScript, Redux, Ant Design.
Frontend Developer at League Digital
December 31, 2021 - September 19, 2025Worked on DSTV and Multichoice websites, converting wireframes to HTML, SCSS, JavaScript, React, and Twig. Integrated with Umbraco CMS, displaying dynamic content via Razor views (C#). Contributed to R&D in tools like Storybook.js, Three.js, and GSAP.
Developer at Ozra Media
December 31, 2022 - September 19, 2025Led frontend development of custom websites and applications for clients. Oversaw project design, brand direction, and client communication while mentoring junior devs. Built sites in WordPress, Gatsby.js, and React, with backend work in PHP and custom JS.
Various Roles at Earlier Roles
December 31, 2019 - September 19, 2025Various early roles in development and related functions described in the resume.
Education
Bachelor of Commerce in Information Systems & Business Management at University of South Africa
January 11, 2030 - January 1, 2017Bachelor of Commerce in Information Systems & Business Management at University of South Africa
January 11, 2030 - January 1, 2017Bachelor of Commerce in Information Systems & Business Management at University of South Africa
January 11, 2030 - January 1, 2017Bachelor of Commerce in Information Systems & Business Management at University of South Africa
January 11, 2030 - January 1, 2017Bachelor of Commerce in Information Systems & Business Management at University of South Africa
January 11, 2030 - January 1, 2017Qualifications
GraphQL Certification – Apollo
January 11, 2030 - September 19, 2025Three.js Journey – Bruno Simon
January 11, 2030 - September 19, 2025React – The Complete Guide (Udemy)
January 11, 2030 - September 19, 2025Modern JavaScript (ES6 & ES7) (Udemy)
January 11, 2030 - September 19, 2025GraphQL Certification – Apollo
January 11, 2030 - September 19, 2025React – The Complete Guide
January 11, 2030 - September 19, 2025Node.js & Express.js – John Smilga
January 11, 2030 - September 19, 2025Three.js Journey – Bruno Simon
January 11, 2030 - September 19, 2025GraphQL Certification – Apollo
January 11, 2030 - September 19, 2025GraphQL Certification – Apollo
January 11, 2030 - September 19, 2025GraphQL Certification – Apollo
January 11, 2030 - September 19, 2025React – The Complete Guide (Udemy)
January 11, 2030 - September 19, 2025Three.js Journey – Bruno Simon
January 11, 2030 - September 19, 2025Java – Codecademy
January 11, 2030 - September 19, 2025Industry Experience
Software & Internet, Media & Entertainment, Education, Financial Services, Professional Services, Telecommunications, Retail
Skills
Experience Level
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
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