Kristina is available for hire

Kristina Grujic

Verified Expert in Engineering

Software Developer

Novi Sad, Vojvodina, Serbia

Toptal member since July 16, 2020

Expertise

Git CSS JavaScript React.js Redux GitHub Web Development HTML5 TypeScript GraphQL Next.js Tailwind CSS

Bio

Kristina is a passionate front-end engineer with 10 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 led technical projects and mentored colleagues. Kristina is known for delivering clean and maintainable, high-quality code delivered with fast turnaround times.

Portfolio

Netronix

Agile, Git, Android Studio, Xcode, Enzyme, Appium, Jest, Redux-Saga, Redux...

Elligencia

React, React Native, Chart.js, SVG Animation, Expo, Tailwind CSS, Next.js...

Synechron

REST, GraphQL, TestCafe, Storybook, Appium, Enzyme, Jest, Redux, React Native...

Experience

Git - 12 years
CSS - 11 years
JavaScript - 11 years
Redux - 10 years
React Native - 10 years
React - 10 years
Jest - 4 years
GraphQL - 3 years

Availability

Full-time

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 - 2024

Netronix

Developed the mobile application for the AirThinx IoT product—an air quality monitor that allows users to see the air quality they breathe in, all of the essential parameters, and set notifications when the air quality drops.
Integrated NestJS to further optimize heating and cooling based on alerts fired by the app.
Delivered a complete 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, Visual Studio Code (VS Code), HTML5, React Redux, GitHub, JavaScript, Web Development, CSS, Mobile App Development, Front-end Development, Figma, Teamwork, Complex Application User Interfaces (UI)

Senior Front-end Developer

2021 - 2023

Elligencia

Developed a widget that can be embedded into any website, using React, allowing for the display of sentiment analysis data provided by the Ellisense API.
Built the Ellisense website to provide extensive sentiment analysis data for stocks, crypto, and foreign currencies.
Developed an MVP React Native app for Ellisense, with various chart implementations displaying live data.
Created a UI system and base components shared by the Ellisense website and widget.

Technologies: React, React Native, Chart.js, SVG Animation, Expo, Tailwind CSS, Next.js, Web Extensions, Visual Studio Code (VS Code), HTML5, React Redux, GitHub, JavaScript, Git, Web Development, CSS, Mobile App Development, Front-end Development, GitLab, Teamwork, Complex Application User Interfaces (UI)

Technology Lead

2018 - 2020

Synechron

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, Visual Studio Code (VS Code), HTML5, React Redux, Web Development, CSS, Front-end Development, GitLab, Teamwork, Complex Application User Interfaces (UI)

Front-end Developer

2017 - 2020

Emvisage

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, Visual Studio Code (VS Code), HTML5, React Redux, GitHub, JavaScript, Web Development, CSS, Front-end Development, Teamwork, Complex Application User Interfaces (UI)

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, Visual Studio Code (VS Code), HTML5, React Redux, GitHub, Web Development, Mobile App Development, Front-end Development, GitLab, Teamwork, Complex Application User Interfaces (UI)

Full-stack Developer

2016 - 2018

Kolosek

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, HTML5, React Redux, GitHub, Web Development, Mobile App Development, Front-end Development, Teamwork, Complex Application User Interfaces (UI)

Experience

AirThinx Mobile Application

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

CastleKeyp

A React Native hybrid application that is fully end-to-end encrypted, guaranteeing information sharing only between the user and the people they choose. It included the implementation of push notifications, advanced calendar usage, and various form implementations.

Education

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

Skills

Libraries/APIs

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

Tools

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

Languages

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

Frameworks

React Native, Redux, Jest, Vanilla JS, Next.js, Tailwind CSS, Appium, TestCafe, Cerebral

Paradigms

Software Testing, Agile, REST, Scrum

Platforms

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

Storage

Linter SQL RDBMS

Other

Front-end Development, Teamwork, Mobile App Development, Web Development, Storybook, Enzyme, Complex Application User Interfaces (UI), Software Development, Software Engineering, i18n, Web Extensions, SVG Animation, Social Networks Development, Calendars, App UX, Web UX

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