
Petur Subev
Verified Expert in Engineering
Software Developer
Sofia, Bulgaria
Toptal member since July 26, 2021
Petur is a staff front-end engineer with 10+ years of experience crafting scalable, performant web apps. Most recently at V7, he led front-end architecture for an AI-first platform, building responsive UIs with Vue.js and TypeScript while mentoring engineers and driving performance optimization. At Hyperscience, he built advanced React dashboards powered by real-time AI predictions. He excels in fast-paced, product-driven environments.
Portfolio
Experience
- JavaScript - 10 years
- TypeScript - 7 years
- React - 5 years
- Vue 3 - 4 years
- Vitest - 3 years
- Tailwind CSS - 2 years
- Express.js - 2 years
- Socket.IO - 2 years
Preferred Environment
TypeScript, JavaScript, React, Node.js, Express.js, Vue, Playwright, Tailwind UI, Jest
The most amazing...
...thing is how my Neovim setup and macro-powered keyboard turn front-end work into flow—I'm a developer who codes like it's a craft.
Work Experience
Staff Front-end Engineer
V7
- Led front-end architecture and development at V7, delivering advanced AI-assisted labeling tools and modular UI components for large-scale datasets.
- Built and maintained a scalable Vue.js + TypeScript component library at V7, enabling rapid product iteration across multiple teams and features.
- Engineered high-performance UIs using virtualization and lazy loading, supporting seamless interaction with millions of data points in-browser.
Staff Software Engineer
HyperScience
- Assisted the team that handles the extraction of tabled data of scanned documents.
- Implemented a new DatePicker component widely used within the product.
- Migrated legacy components from Flow to TypeScript.
Staff Software Engineer - Front-end Lead
Leanplum
- Oversaw the entire front-end ecosystem, from setting up the build, the tools, the frameworks, the libraries, and adding and updating the style guidelines.
- Introduced TypeScript, migrated many pages from AngularJS to Vue.js and introduced Vuex.
- Led front-end meetings advised FE colleagues on areas for improvement provided feedback to easily reach the next level in their career growth.
Senior Software Engineer
Leanplum
- Oversaw the entire front-end ecosystem, from setting up the build, the tools, the frameworks, the libraries, and adding and updating the style guidelines.
- Introduced TypeScript, migrated many pages from AngularJS to Vue.js and introduced Vuex.
- Assisted in creating a composer and campaign results.
Software Developer
Progress
- Researched, designed, tested, and developed widgets such as a grid (table), treeviews, dropdowns, and charts.
- Built an interactive online coding editor that is tightly integrated with the live demonstrations allowing users to quickly extend existing examples and share them.
- Guided users on StackOverflow to fine-tune their widgets.
- Provided technical support over several channels including phone assistance.
Experience
Campaign Composer
https://docs.leanplum.com/docs/add-multiple-actionsCampaign Results
https://docs.leanplum.com/docs/campaign-flowCampaigns Overview
https://docs.leanplum.com/docs/campaigns-overviewKendo UI Dojo
https://dojo.telerik.com/DatePicker, Based on React Hooks and Date-fns
V7 Darwin
https://docs.v7labs.com/docs/use-workflows-to-manage-your-projectsThe builder allows users to chain actions such as model inference, human review, logic branching, and QA into visual workflows tailored to each dataset. I collaborated closely with product managers and back-end engineers to translate dynamic graph logic into an intuitive, drag-and-drop interface.
To maintain high responsiveness while handling large graphs, I implemented virtual scrolling and smart rendering techniques. I also designed reusable components and internal tooling that significantly reduced development time for new workflow features. This builder became a core part of the V7 product offering, improving customer onboarding and automation speed across enterprise clients in biotech, autonomous driving, and retail.
Table View and Entity Management UI in V7 Go
https://docs.go.v7labs.com/docs/using-the-file-propertyI implemented the Table View using Vue.js and TypeScript, architecting it for performance, scalability, and extensibility. I introduced virtualization and lazy loading to handle tens of thousands of data rows with smooth scrolling and interaction. The data model supported custom field types (text, dropdowns, files, booleans, etc.), all dynamically configurable via the UI.
In close collaboration with design and product teams, I helped shape an experience where users could define, annotate, and track metadata across large-scale AI pipelines—powering tasks like multi-label classification, data filtering, and agent-driven automation.
The result was a flexible and intuitive workspace that served as the primary control panel for V7 Go customers, accelerating data readiness for training and deployment.
Education
Master's Degree in Computer Science
Technical University Sofia - Sofia, Bulgaria
Bachelor's Degree in Computer Science
Technical University Sofia - Sofia, Bulgaria
Certifications
Certified Scrum Master
Scrum Alliance
MCPS: Microsoft Certified Professional
Microsoft
Skills
Libraries/APIs
React, Vuex, Vue 2, jQuery, RxJS, Vue, Lodash, Vue 3, React Router, Node.js, Socket.IO, Moment.js, Protobuf, Ramda, GoJS, Playwright
Tools
Vitest, Git, JSX
Languages
TypeScript, JavaScript, CSS, HTML, C#, SCSS, Java, Python, Sass
Frameworks
AngularJS, Jest, Tailwind CSS, .NET, Express.js, Razor, ASP.NET MVC, Redux, Django, Jasmine
Paradigms
Scrum
Storage
JSON
Other
React Hooks, Web Development, Pinia, Algorithms, Data Structures, Software Development, Engineering, Computer Science, WebSockets, Small Computer System Interface (SCSI), Axios, Vue Router, Tailwind UI
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