Kristina Grujic, Developer in Novi Sad, Vojvodina, Serbia
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Kristina Grujic

Verified Expert  in Engineering

Software Developer

Novi Sad, Vojvodina, Serbia
Toptal Member Since
July 16, 2020

Kristina is a passionate front-end engineer with over four years of experience specializing in React and React Native projects. Her valuable input and development skills on the IoT product AirThinx, won the New Product Innovation award in 2019 by Frost & Sullivan and the Top Project award in 2018. She has lead technical projects and mentored colleagues. Kristina is known for delivering clean and maintainable, high-quality code delivered with fast turnaround times.


Agile, Git, Android Studio, Xcode, Enzyme, Appium, Jest, Redux-Saga, Redux...
REST, GraphQL, TestCafe, Storybook, Appium, Enzyme, Jest, Redux, React Native...
Linter SQL RDBMS, Jest, Storybook, i18n, Cerebral, Git, Redux Thunk, Redux...




Preferred Environment

Slack, Visual Studio Code (VS Code), MacOS

The most amazing...

...IoT product I drove was AirThinx - an air quality monitor. It won the New Product Innovation (2019) and the Top Project (2018) award by Frost & Sullivan.

Work Experience

Senior Front-end Engineer

2019 - PRESENT
  • Developed the mobile application for the AirThinx IoT product - air quality monitor that allows users to see the air quality they breathe in all of the important parameters and set notifications on when air quality drops.
  • Integrated Nest to further optimize heating and cooling based on alerts fired by the app.
  • Delivered a full redesign and refactor of the app as the sole React Native developer in the team.
Technologies: Agile, Git, Android Studio, Xcode, Enzyme, Appium, Jest, Redux-Saga, Redux, React Native

Technology Lead - JavaScript

2018 - 2020
  • Acted as tech lead for a team consisting of 15 people for a React technology.
  • Conducted technical interviews and mentored new colleagues.
  • Developed the internal web application for a French asset management client.
  • Developed common UI tools and libraries used across multiple projects.
Technologies: REST, GraphQL, TestCafe, Storybook, Appium, Enzyme, Jest, Redux, React Native, React, JavaScript

Front-end Developer

2017 - 2020
  • Developed a form builder component with resize, reorder, drag, and drop fields. Forms rendered from JSON structures allowing users to define whatever they want the form to do.
  • Built a web platform for business workflow management.
  • Created a rule engine for a front-end application to handle various validations.
  • Built a custom watcher behavior for input fields.
Technologies: Linter SQL RDBMS, Jest, Storybook, i18n, Cerebral, Git, Redux Thunk, Redux, React

Front-end Developer

2016 - 2020
Freelancer - Contractor Agency
  • Developed a number of projects for clients all worldwide.
  • Designed a custom React gallery with a pinch, pan, swipe, and zoom behavior fully supported by all browsers.
  • Developed various applications working with maps, live, and push notifications.
Technologies: ZenHub, Trello, Jira, Git, JavaScript, HTML, CSS3, CSS, React Native, React

Full-stack Developer

2016 - 2018
  • Developed a React Native application: a social network for business people to appraise each other within the company and between colleagues and ex-colleagues.
  • Mentored colleagues transitioning to React technology. Acted as the technology lead for React/React Native projects.
  • Assisted in the development of the back end and web application for the same social networking app where I was lead for mobile app development, while handling multiple small- to medium-sized projects.
Technologies: Git, Scrum, Enzyme, Jest, REST, GraphQL, Redux, CSS, HTML, JavaScript, Node.js, React Native, React

AirThinx Mobile Application
This React Native multi-platform application allows users to see the air quality reported by AirThinx devices and specify interactions with other integrated IoT devices based on various alerts, and to be notified on parameter value change out of specific profile zone.
2019 - 2021

Master's Degree in Software Engineering

University of Novi Sad - Novi Sad, Serbia

2013 - 2018

Bachelor's Degree in Software Engineering

University of Novi Sad - Novi Sad, Serbia


React, React Redux, Node.js, Redux-Saga


Git, GitHub, Bitbucket, Jira, Xcode, Android Studio, Slack, Redux Thunk, Trello, ZenHub


React Native, Redux, Jest, Vanilla JS, Appium, TestCafe, Cerebral


CSS, HTML, JavaScript, HTML5, TypeScript, GraphQL, CSS3




Software Testing, Agile, REST, Scrum


Android, Firebase, MacOS, Visual Studio Code (VS Code)


Mobile App Development, Web Development, Storybook, Enzyme, Software Development, Software Engineering, i18n

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