Petar Simic
Verified Expert in Engineering
Single-page Applications (SPAs) Developer
Belgrade, Serbia
Toptal member since November 18, 2014
Petar has extensive experience in developing web applications and custom JavaScript libraries. He is a highly responsible team player and a passionate coder who is always looking for challenge and perfection. He is very good at resolving user interface problems and interaction, and prides himself on his tenacity in solution building.
Portfolio
Experience
- Single-page Applications (SPAs) - 14 years
- JavaScript - 14 years
- Responsive Layout - 10 years
- Content Management Systems (CMS) - 8 years
- React - 5 years
- Node.js - 5 years
- Angular - 4 years
- Elasticsearch - 3 years
Availability
Preferred Environment
Visual Studio Code (VS Code), Git, Ubuntu, Figma, Docker, Docker Compose, Elastic, Kibana
The most amazing...
...thing I've created is a dynamic web application that allows users to create multiple desktops with widgets for different data types and a social function.
Work Experience
Senior Full-stack Engineer
Jollydays
- Designed and developed a CMS that enabled the manipulation and configuration of campaigns with data related to events of different types and content in various time intervals, at specific geographic locations, or virtually.
- Developed the client API using Node.js, which stored data in the Elastic database, and the user interface with React that simplified the creation of event campaigns.
- Used content relevant to the created campaign on the client-side website and filters for the user-provided terms, thus enabling fast and accurate results.
- Planned and tracked everything in Jira within daily calls and bi-weekly team planning and reviews.
Senior Full-stack Developer
Vertrical
- Developed many specific modules for querying and UI rendering, using Elasticsearch, Node.js, Gatsby, React, HTML, and CSS.
- Tracked and fixed issues in Elasticsearch queries, including optimizations and boosting query response time.
- Planned teamwork, organized tasks and bugs owners, tracked team progress and support, and debugged blockers.
JavaScript/Angular Developer
Online Freelance Agency
- Created a reusable data manager to manipulate response objects from any API configuration easily. Also supports deep binding directly on a model structure, so in return, it provides first-level data for fast-performance reading and writing.
- Developed a reusable parser to manage several viewable items for any platform and view type (list, grid, etc.) with a simple configuration file. It also supports auto-scrolling and auto-pulling of data from the API.
- Worked as a core team member and maintained agency talent and client platform, providing new features and maintaining reported problems and requests.
JavaScript Engineer
Atmospheric Data Solutions, LLC
- Involved in developing specific features on the dashboard that drew any of the selected layers (e.g., winds, temperature., etc.) and provided animation with changes for the selected timeline (from a few minutes up to 24 hours).
- Collected and parsed all the incoming data and sorted it into a timeline to create frames that were later rendered and animated.
- Kept track of the renderers. As the platform was rapidly developed as a start-up, I had to give my best to fix existing memory leaks and build and deliver new features.
Developer and Team Lead
TNation
- Managed and organized the team and interviewed new candidates. Organized training sessions to improve coding.
- Wrote documentation and specifications for new features.
- Created reusable components that are and can be used across the system. Components determine what the content type is and display that content as a tooltip or modal window.
- Created migration files for seeding data and manipulating with column names and value types, using Sequelize.
- Refactored existing components covered with tests on both sides using Angular and Node.
- Built new UI components from the provided designs from internal company or client mocks created.
Front-end Developer
BuildFire
- Developed custom-requested applications within the BuildFire SDK.
- Worked with a team of designers and developers on the best UX solution for the final product.
- Improved SDK testing tools, such as building a switch that enables different device screen size views in the testing phase. Also worked on SDK bug fixes.
Developer
Pure Blue Software. LLC.
- Built more than 70% of the components from scratch to make the application as light as possible due to the vast amount of active interactions and event handlers.
- Developed a specific grid system similar to the Google Calendar but with the same experience creating tasks and drag-n-drop positioning in strictly defined columns.
- Built the application was cross-browser compatible, and all the measures were dynamically calculated in case of screen size changes. This also involved repositioning the content and verifying that all tasks were visible to the client.
UI/UX Developer
Pure Blue Software. LLC.
- Developed an application that tracks and organizes employees. Organizers can add and change each employee plan by interacting on the calendar. It's similar to Google Calendar.
- Developed a custom calendar component and custom drag-and-drop component for setting employee tasks, in order to get the best performance. The app had to handle overlapping and organization of UI when multiple tasks were on the calendar.
- Developed different user roles and views of the calendar and employee tasks.
Web Developer
Tailor and Made
- Built websites with full cross-browsing compatibility from all desktop browsers on Windows, Linux, and Mac to all mobile and tablet platforms.
- Created a few quick-loading "single page" static websites which use different types of libraries and components that are optimized to work from IE8+.
- Developed custom CSS3 animations for websites, as part of my role.
JavaScript/PHP Developer
Full Dream Solutions
- Created data communication between Unity3D (mobile, web) and different type of APIs like Shopify.
- Built a MySQL DB with RESTful APIs for a multiplayer game.
- Programmed a reusable JSON parser in C# that manages particular types of data as requested on one gaming product.
Lead Front-end Engineer and Team Lead
Whitecitysoft
- Collaborated to create a custom JavaScript MVC framework that saves implementation time and spares developers the hassle of working with HTML structures by managing everything over a controller setup and hierarchy of controllers.
- Created hundreds of different widgets built from ten simple templates. All of them are specially made to be implemented modularly and give the developer an opportunity to create new widgets with a minimum of testing.
- Planned and researched UI on most projects to find the best optimal solution for all three sides, including designers, developers, and users, so building projects with a streamlined user interface will work more quickly in the future.
- Organized team members and managed code quality control.
- Took full responsibility for the system as a whole and performed training of new staff.
Web Developer
Freelance
- Developed a static website with a Flash introduction page.
- Implemented multi-language support with basic CMS using PHP scripts to provide easier editing of the website text content.
- Conducted SEO optimization. Implemented email subscribe for guests and newsletter.
Volunteer Java, JavaScript, and Delphi Programmer
Red Cross
- Created an MDI application in Java and Delphi for managing data.
- Built a generic application that is able to build independently and manage user interfaces based on database XML schematics.
- Supported offline (local) and online (server) data storage with auto-synchronization when the app connects to the internet.
Experience
Online Directory
This application supports profile creation, reviews, and comments on different businesses. Users gain various levels of badges based on the experiences they share and are also allowed to upload photos and bookmark favorite businesses. Sharing is supported on all major applications. The application is compatible with all platforms, including mobile devices and old browsers.
Earthquake Simulator
https://earlywarninglabs.com/Regex Generator
Interactive Organizer
Virtual Boards/Item Manager
Website Video Channel
Custom Management Tool for Air Company
Website with Focus on Annual Reports In-Company
Web Application for Selling Gifts and Vouchers
Cinema Advertising Company
Nialaya
https://www.nialaya.com/Cost Plus Drugs
https://costplusdrugs.comSearch Engine Web Application
https://searchubxxx.com/This single-page application (SPA) was crafted using JavaScript, the Angular framework, and essential web technologies such as HTML and CSS. My role extended beyond mere coding—I actively participated in enhancing UI/UX elements, ensuring a seamless and intuitive user experience.
Document Imaging Application
https://infasme.com/In my role, I played a crucial part in developing and optimizing a custom grid generator. This tool replicates the functionality of Microsoft Excel within a web browser, allowing users to view and print data in a formatted manner consistent with the original documents. Utilizing JavaScript, Bootstrap, CSS, HTML, and jQuery, I ensured that the grid generator provided a user-friendly experience while maintaining robust functionality and adherence to design specifications.
Education
Bachelor's Degree in Software Engineering
Metropolitan University - Belgrade, Serbia
Skills
Libraries/APIs
React, Preact, Node.js, jQuery, Shopify API, Backbone.js, Chart.js, Python API, OpenLayers, jQuery UI
Tools
Git, Figma, Webpack, Elastic, Adobe Photoshop, Docker Compose, Kibana, Adobe Flash, Zeplin, Web GIS
Languages
JavaScript, CSS3, XML, HTML, CSS, HTML5, TypeScript, GraphQL, TypeScript 2, SQL, Sass, Less, SCSS, PHP, Regex, Python
Frameworks
Angular, AngularJS, Next.js, Tailwind CSS, Jest, JavaScriptCore, NestJS, Vanilla JS, Bootstrap
Paradigms
Responsive Layout, REST, Responsive Web Design (RWD), Object-oriented Programming (OOP), Agile Software Development, Unit Testing, Microservices
Platforms
Visual Studio Code (VS Code), Docker, Google Cloud Platform (GCP), Web
Storage
Elasticsearch, MySQL
Other
Responsive UI, Responsive Web Apps, User Interface (UI), Single-page Applications (SPAs), Content Management Systems (CMS), Web Standards, Quick Study, User Experience (UX), Dom Manipulation, Gatsby, Graphic Design, Data Modeling, Software Engineering, Regular Expressions, Web UX, XD to HTML, Wireframe to Product, ECM, Front-end, NetCDF
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