Hesam Hosseini

Hesam Hosseini

Senior Frontend Developer

About Me

I am a Senior Frontend Developer with over 4 years of professional experience building modern, scalable, and high-performance web applications. I specialize in React, Next.js (App Router), TypeScript, and Tailwind CSS, with a strong focus on pixel-perfect UI implementation, cross-team collaboration, and UX optimization. I work full-time at Vikarno while also developing crypto finance platforms at Qaay and handling freelance projects. I'm deeply passionate about delivering fast, accessible, and multilingual web apps, and I'm known for:

  • •High-speed delivery and clean code
  • •Deep integration of design into development
  • •Precise execution of UI/UX
  • •Excellent communication within product teams
Hesam Hosseini

Experience

Qaay (Crypto Finance)

Senior Frontend Developer

May 2025 - Present

Developed a comprehensive crypto finance dashboard using Next.js 15 and TypeScript, featuring portfolio management, lending, borrowing, swap, deposit, and withdrawal modules; utilized App Router, SSR/ISR, and route middleware to deliver fast and secure user experiences. Designed and implemented a highly reusable UI system with design tokens, memoized selectors, list virtualization, and Suspense-friendly custom hooks, reducing unnecessary re-renders by ~45% and cumulative layout shift (CLS) by ~30% across the entire platform. Implemented full internationalization (i18n) with RTL support for English and Farsi using edge middleware and localized routing. Integrated Payload CMS for content and admin panels while strengthening authentication flows with secure OTP verification and robust session management. Established a modern CI/CD pipeline using Docker and Bitbucket Pipelines with automated linting and test gates. Collaborated with designers, backend engineers, and product teams to integrate UI components and features, maintaining high code quality and reducing integration issues.

Vikarno

Senior Frontend Developer

March 2025 - Present

Frontend Tech Lead on multiple products at Vikarno spanning AI, SaaS, and e-commerce. Led VIGPT (vigpt.ai), a bilingual (Persian/English) AI platform combining conversational chat with multi-model image and video generation — GPT, Kling, Seedream, Flux Kontext, Veo, and more — behind a unified AI gateway; architected and developed it end-to-end across a Next.js monorepo spanning the web app, a BullMQ/Redis worker, and a mobile app (Expo + React Native). Implemented phone/OTP authentication and a subscription billing system with an append-only ledger for usage-based billing, and engineered resumable streaming, in-browser Python code execution, and approval-gated AI tool calling for agentic workflows. Also developed VIRA Sign (virasign.com), a digital contract and e-signature platform with two-factor identity verification and HR/accounting system integrations, and DrErfanOrchid.com, a multilingual flower-shop e-commerce platform with multi-warehouse and multi-location management. Delivered full Persian RTL localization and a custom ShadCN-based design system across web and mobile, and applied advanced rendering and caching strategies that cut key route load times by up to 1.5 seconds across critical routes.

Hoopad Vision

Senior Frontend Developer

June 2024 - March 2025

Developed a fully functional and interactive report page using Highcharts library in React.js, enabling data visualization and analytics for over 1,000 monthly active users, leading to a 15% increase in user engagement. Implemented multi-language support in Next.js 14 applications, leveraging internationalization (i18n) libraries to support 3+ languages, improving accessibility for a global user base. Engineered scalable and performant web applications using Next.js App Router, combining SSR (Server-Side Rendering) and CSR (Client-Side Rendering) techniques to optimize load times and enhance user experience, resulting in a 2-second reduction in page load times. Collaborated with backend and design teams to ensure seamless integration of APIs and UI components, reducing integration-related issues by 20%. Conducted rigorous testing and debugging, maintaining 98% code coverage and minimizing production bugs, leading to a 30% decrease in post-release issues.

Freelance Developer

Frontend Developer

June 2024 - March 2025

Engineered high-performance applications using Next.js 14, optimizing user experience through SSR and CSR techniques, resulting in a significant increase in user satisfaction scores. Customized and utilized the ShadCN component library, achieving a consistent and reusable UI across multiple projects. Implemented advanced rendering strategies, enhancing scalability and efficiency of web applications, leading to 1.5 seconds improvement in load times. Conducted thorough testing and debugging, maintaining high-quality standards and minimizing production issues, reducing bug-related incidents by approximately 40 incidents. Collaborated with design and development teams, ensuring seamless UI component integration and reducing integration issues by around 10 major incidents.

MyData-co

Frontend Developer

November 2022 - June 2024

Refactored and analyzed code, improving readability and maintainability, leading to easier future updates and modifications, saving over 150 hours. Developed and maintained a custom UI kit using SCSS, increasing the reusability of components and reducing customization time by around 120 hours. Delivered a project with Next.js 13, focusing on modern web development practices and performance optimization, reducing page load times by over 2 seconds. Contributed to products that are currently used by over 100,000 users, significantly impacting user engagement and satisfaction. Optimized application performance, resulting in over 5 hours faster load time and a notable increase in user engagement.

Maktab Sharif

Teaching Assistant

August 2022 - July 2025

Taught HTML and CSS for building and styling web pages, and JavaScript (ES6, ES7) fundamentals and advanced features to over 300 students. Instructed students on TypeScript fundamentals, enabling robust, type-safe code development, resulting in a 30% improvement in student project stability. Guided students through React.js, including hooks, routing, custom hooks, HOC, and state management. Educated on version control with Git and GitHub, including branching, merging, and pull requests, increasing student collaboration efficiency by 30%. Tutored students in testing and debugging web applications using Jest and React Testing Library, improving test coverage by 40%.

Skills

Self-assessed. Select a skill to see what its band means.

Languages & Frameworks10

Tools & Technologies26

Design & Collaboration6

Projects

VIGPT
VIGPT
A bilingual (Persian/English) AI platform I developed end-to-end at Vikarno, combining conversational chat with multi-model image and video generation (GPT, Kling, Seedream, Veo, and more). Includes phone/OTP auth, subscription billing with an append-only ledger, resumable streaming, in-browser Python execution, and approval-gated AI tool calling across web and mobile.
Next.js
TypeScript
AI Gateway
BullMQ
Redis
PostgreSQL
MinIO
React Native
VIRA Sign
VIRA Sign
A digital contract and e-signature platform I worked on and developed at Vikarno, targeting organizations that need secure, paperless personnel contracts. Features two-factor identity verification (national ID, phone, and government photo matching), fingerprint and handwritten digital signatures, a dispute-resolution workflow, and integrations with HR/accounting systems.
Next.js
TypeScript
Payload CMS
PostgreSQL
Tailwind
React Hook Form
DrErfanOrchid.com
DrErfanOrchid.com
A flower shop e-commerce platform I designed and developed for Vikarno, with multi-language support, multi-warehouse management, and multi-location functionality.
Next.js
SSR
ShadCN
i18n
Caching Systems
Qaay.com
Qaay.com
A comprehensive crypto finance dashboard featuring portfolio management, lending, borrowing, swap, deposit, and withdrawal modules. Developed with Next.js 15, utilizing App Router, SSR/ISR, and route middleware for fast and secure user experiences. Features ~45% reduced re-renders and ~30% improved CLS.
Next.js 15
TypeScript
SSR/ISR
Payload CMS
Docker
i18n

Contact Me

Feel free to reach out to me through any of the following channels or by filling out the form.