Cristian Calniciuc

Cristian Calniciuc

Senior Full Stack Developer 

Steiermark, Graz, 8041, Austria | https://github.com/donehello

PROFILE SUMMARY

Results-driven full-stack software engineer with over 6 years of experience designing and building scalable, high-performance web and mobile applications across diverse industries, including healthcare, fitness, SaaS, real estate, and biotech. Passionate about developing efficient, secure, and user-centric solutions that enhance functionality and drive business success.

A proven leader in architecting complex systems, optimizing performance, and implementing modern development practices, I thrive in collaborative environments, working seamlessly with cross-functional teams to deliver cutting-edge features, product enhancements, and continuous improvements. Adept at working in remote-first settings, ensuring productivity, innovation, and technical excellence.

Committed to driving innovation, solving complex challenges, and mentoring teams to elevate engineering standards and product quality.

SKILLS

Frontend Development:

✅ Expert in crafting responsive, high-performance UIs with HTML5, CSS3, JavaScript, TypeScript, and PHP

✅ Strong understanding of Component-Based Architecture, Virtual DOM, and State Management

✅ Specialized in Single Page Applications (SPA) and Progressive Web Apps (PWA) for seamless user experience

✅ Ensures cross-browser compatibility and mobile-first design principles

✅ Debugging and optimizing frontend performance for fast load times and accessibility compliance

Frontend Frameworks & Libraries:

✅ Mastery of React.js, Angular, and Vue.js for dynamic web apps

✅ State management expertise using Redux, Vuex, Context API, and Zustand

✅ UI/UX frameworks: Material-UI, Tailwind CSS, Ant Design, Bootstrap, Styled Components

✅ Advanced data visualization with D3.js, Chart.js, and Three.js

✅ Extensive experience in Laravel, CodeIgniter, and WordPress, Framer, Webflow for web applications

Backend Development:

✅ Backend proficiency in Node.js (Express.js, Nest.js, Fastify), PHP (Laravel, CodeIgniter), Python (Django, Flask), Java (Spring Boot), and .NET (ASP.NET Core), Solidity

✅ Design and implement scalable, secure RESTful APIs and GraphQL APIs

✅ Proficient in authentication strategies (OAuth, JWT, OpenID) and security best practices

✅ Strong experience with Microservices Architecture and Serverless Computing (AWS Lambda, Google Cloud Functions)

✅ Asynchronous processing using RabbitMQ, Kafka, Redis, and WebSockets

Databases & Storage:

✅ Expertise in SQL databases: MySQL, PostgreSQL, MSSQL, Oracle

✅ NoSQL databases: MongoDB, Firebase, Redis, DynamoDB, CouchDB

✅ Database Optimization: Query tuning, indexing, replication, caching strategies

✅ Experience with ORMs: Sequelize, TypeORM, Prisma, Hibernate

APIs & Integration:

✅ RESTful APIs, GraphQL, gRPC, JSON-RPC, WebSocket

✅ OAuth 2.0, OpenID, JWT, API Gateway (Kong, NGINX, AWS API Gateway)

✅ Webhooks and third-party API integrations (Stripe, Twilio, SendGrid, Firebase, Algolia, Google Maps)

✅ CORS & CSRF Protection, API rate limiting for security

Cloud & DevOps:

✅ AWS Services: EC2, S3, RDS, Lambda, CloudFormation, ECS, Amplify

✅ Google Cloud & Firebase: Firestore, Cloud Functions, Hosting, Cloud Storage

✅ Containerization & Orchestration: Docker, Kubernetes, Helm, OpenShift

✅ Infrastructure as Code (IaC): Terraform, CloudFormation

✅ CI/CD Pipelines: Jenkins, GitHub Actions, GitLab CI/CD, Travis CI, CircleCI

✅ Monitoring & Logging: Prometheus, Grafana, ELK Stack (Elasticsearch, Logstash, Kibana), Datadog

Build Tools & Package Managers:

✅ Webpack, Babel, Grunt, Gulp, Vite

✅ Package managers: npm, Yarn, pnpm

Version Control & Collaboration:

✅ Git, GitHub, GitLab, Bitbucket

✅ Agile & Scrum methodologies using Jira, Trello, ClickUp, Asana

✅ Strong remote team collaboration experience in globally distributed teams

PROFESSIONAL EXPERIENCE

- Web/Mobile Developer (Freelancer.com)                 AUG 2024 — present

Skills: Vue.js, React.js • Full-Stack Development • Front-End Development

- Senior Full Stack Developer   Electra Protocol                        JAN 2024 — AUG 2024

    Designed and implemented scalable full-stack solutions, integrating React.js, Angular, and Node.js for enterprise applications.Developed reusable UI components and design systems to ensure consistency and efficiency across multiple projects.

    Developed reusable UI components and RESTful APIs, ensuring seamless interaction between frontend and backend services.

    Built and optimized database queries using PostgreSQL and MongoDB, enhancing data retrieval efficiency.

    Automated testing and CI/CD deployment workflows, improving development speed and reliability.

    Integrated authentication and security protocols (OAuth, JWT, Role-Based Access Control) for secure user management.

    Collaborated with UI/UX designers to deliver responsive, high-performance applications, reducing page load times by 30%.

Technologies/Tools: 

•  Frontend: React.js, Angular, Next.js, TypeScript, JavaScript (ES6+), Vue.js

•  Backend: Node.js, Express.js, NestJS, GraphQL

•  Authentication & Security: OAuth, JWT, Role-Based Access Control (RBAC)

•  Performance Optimization: Code-Splitting, Lazy Loading, Memoization, Virtual DOM, Server-Side     Rendering (SSR), Progressive Web Apps (PWA)

- Full-Stack Blockchain Developer     Lila Finance                     MAY 2023 — JAN 2024

    Developed and maintained the Lila Finance DeFi platform using React.js, Angular, Redux, and Tailwind CSS, ensuring a seamless and efficient user experience. 

    Designed and implemented Ethereum-based smart contracts using Solidity, enabling secure and transparent DeFi transactions.

    Integrated Web3.js to facilitate blockchain interactions, allowing users to seamlessly connect wallets and perform transactions.

    Built and optimized RESTful APIs and GraphQL endpoints using Node.js and Express.js to enable smooth communication between the frontend and blockchain network.

    Enhanced performance, scalability, and security by implementing gas optimizations and smart contract best practices.

    Collaborated with UI/UX designers, blockchain engineers, and backend developers to create a robust, user-friendly decentralized application (dApp).

    Contributed to CI/CD pipelines, automated testing, and smart contract audits, ensuring secure and efficient deployments.

Technologies/Tools: 

•  Frontend: React.js, Angular, Redux, TypeScript, JavaScript, Tailwind CSS

•  Backend: Node.js, Express.js, GraphQL

•  Blockchain & Smart Contracts: Solidity, Web3.js, Ethers.js, Hardhat, Truffle

•  Databases: PostgreSQL, MongoDB, Firebase

•  DevOps & Security: GitHub, CI/CD, Webpack, Smart Contract Audits

•  Design & Prototyping: Figma

- Full-Stack Developer      Doveswap(Dovish Finance)                     MAY 2022 — APRIL 2023 

    Developed the frontend of a decentralized exchange (DEX) and perpetual trading platform using TypeScript, Vue.js, and Vite, ensuring a seamless trading experience.Designed intuitive, responsive, and visually engaging user interfaces, enhancing UX/UI design and user satisfaction.

    Designed intuitive, responsive, and visually engaging user interfaces, enhancing UX/UI design and user satisfaction.

    Built and integrated RESTful APIs, WebSockets, and GraphQL to ensure real-time data updates and smooth frontend-backend communication.

    Implemented state management solutions like Pinia and Vuex, improving application scalability and maintainability.

    Integrated third-party APIs to expand platform functionality and improve trading features.

    Technologies/Tools:

•  Frontend: Vue.js, Nuxt.js, React.js, TypeScript, JavaScript, HTML5, CSS3, Tailwind CSS

•  Backend: Node.js, Express.js, GraphQL

•  State Management: Vuex, Pinia, Redux, Zustand

•  Build Tools & Frameworks: Vite, Webpack, Babel, ESLint, Prettier

•  API & Backend Integration: RESTful APIs, GraphQL, WebSockets, Axios, tRPC

- Full-Stack Developer     MoonStar                                     FEB 2022 — MAY 2022 

    Developed dynamic, interactive, and data-driven user interfaces using Vue.js, React.js, and TypeScript, improving user engagement and responsiveness.Optimized UI responsiveness and performance using Tailwind CSS, SCSS, and CSS-in-JS, ensuring seamless cross-device and cross-browser compatibility.

    Built and optimized backend services using Django and Node.js, implementing RESTful APIs and GraphQL for efficient data processing.

    Developed and deployed Python web scraping scripts using BeautifulSoup and Scrapy, automating data extraction and processing.

    Integrated AWS services such as S3 for storage, Lambda for serverless functions, and EC2 for scalable hosting, ensuring high availability and performance.

    Optimized UI performance and responsiveness with Tailwind CSS, SCSS, and CSS-in-JS, ensuring seamless cross-device compatibility.

    Enhanced web accessibility (a11y) by following WCAG guidelines, implementing semantic HTML, ARIA roles, and keyboard navigation support.

    Implemented frontend security best practices, including input validation, CORS handling, and XSS/CSRF prevention.

    Technologies/Tools:

•  Frontend Development: React.js, Next.js, TypeScript, JavaScript, HTML, Tailwind CSS, Chakra UI

•  Backend Development: Django, Node.js, Express.js, RESTful APIs, GraphQL

•  Python & Web Scraping: Python, BeautifulSoup, Scrapy, Selenium

•  Cloud & DevOps: AWS (S3, EC2, Lambda), Docker, GitHub Actions, GitLab CI/CD

•  State Management: Vuex, Pinia, Redux, Zustand, Recoil

•  API & Backend Integration: RESTful APIs, GraphQL, WebSockets, Axios, Apollo Client, tRPC

- Full-Stack Engineer         LATOKEN                                 JAN 2021 — FEB 2022 

    Led Angular-based projects to develop scalable, high-performance frontend applications for LATOKEN’s platform, utilizing Angular, TypeScript, RxJS, and NgRx.

    Designed and implemented backend services using .NET (C#), Django, and Node.js, developing RESTful APIs and GraphQL endpoints for seamless frontend-backend communication.

    Built and deployed Python web scraping scripts using BeautifulSoup and Scrapy, automating data collection for analytics and market insights.

    Developed microservices and APIs in C#/.NET, optimizing system scalability and maintainability.

    Integrated AWS services, including S3 for storage, Lambda for serverless functions, and EC2 for scalable hosting, ensuring high availability and security.

    Collaborated with designers and backend developers to create responsive, visually engaging, and user-friendly web pages using SCSS, Tailwind CSS, and Material UI.

    Technologies/Tools:

•  Frontend Development: Angular, TypeScript, RxJS, NgRx, HTML, SCSS, Tailwind CSS, Material UI

•  Backend Development: .NET (C#), Django, Node.js, Express.js, RESTful APIs, GraphQL

•  Python & Web Scraping: Python, BeautifulSoup, Scrapy, Selenium

•  Cloud & DevOps: AWS (S3, EC2, Lambda), Docker, GitHub Actions, GitLab CI/CD

•  Database Management: SQL Server, PostgreSQL, MongoDB

EDUCATION

Master’s Degree, Computer Science         

Ovidius University of Constanța, Austria                                    Oct 2016 - Aug 2020    

LANGUAGES

English - Fluent    Romanian - Native Speaker