Freelance full stack developer

Job Title: Full Stack Developer – Perpetual Trading

Location: Remote

Experience: 3+ Years

Employment Type: Full-Time

About the Company

We are a next-generation cryptocurrency exchange focused on building innovative and secure trading experiences for digital assets and derivatives. With a strong emphasis on perpetual trading and real-time market execution, we aim to redefine how traders interact with crypto markets — combining transparency, performance, and user-centric design.

Role Overview

We are seeking a Full Stack Developer experienced in perpetual trading platforms and Web3 ecosystems. The ideal candidate should have hands-on experience working with both frontend (React/Next.js) and backend (Node.js/Nest.js) systems and integrating decentralized perpetual trading APIs such as GMX, Hyperliquid, or similar. You will build end-to-end high-performance trading modules, ensuring low-latency execution, real-time data sync, and seamless user interaction.

Key Responsibilities

• Design, develop, and maintain full-stack trading modules and dashboards for perpetual and derivatives trading.
• Integrate decentralized perpetual trading APIs (GMX, Hyperliquid, Drift, etc.) and Web3 wallets (MetaMask, WalletConnect).
• Implement real-time order books, market data feeds, and trade execution flows using REST and WebSocket APIs.
• Build scalable backend services using Node.js / Nest.js / Express and connect them to the frontend.
• Manage database operations for user data, trade history, and performance analytics.
• Collaborate with UI/UX, blockchain, and DevOps teams to deliver high-performance trading experiences.
• Optimize both frontend and backend for speed, security, and low latency.
• Write clean, maintainable, and modular code following modern development practices and standards.

Required Skills & Experience

• 3+ years of experience as a Full Stack Developer, preferably in crypto, DeFi, or trading platforms.
• Strong proficiency in React.js / Next.js, Node.js / Nest.js / Express, and TypeScript / JavaScript (ES6+).
• Proven experience integrating perpetual trading or DeFi APIs (GMX, Hyperliquid, Drift, etc.).
• Experience with WebSockets for live order books and trade updates.
• Understanding of Perpetual Trading, Futures, and DeFi trading mechanics.
• Hands-on experience with Web3 libraries (ethers.js, web3.js) for wallet and smart contract integration.
• Strong understanding of RESTful APIs, microservices, and database management (PostgreSQL, MongoDB, or similar).
• Familiarity with security best practices, API rate limiting, and user authentication (JWT/OAuth).

Responsibilities:

* Collaborate with cross-functional teams on project requirements and deliverables

* Develop user interfaces using React.JS and Express API's

* Implement database solutions with MongoDB and Node.JS

Job Summary

We are seeking an experienced Java Full Stack Developer with 8+ years of hands-on experience in designing, developing, and maintaining scalable web applications. The ideal candidate should have strong expertise in Java (Spring Boot) on the backend and React.js on the frontend, along with experience in REST APIs, Microservices architecture, and cloud-based deployments.

Key Responsibilities

• Design, develop, and maintain scalable full-stack applications using Java, Spring Boot, and React.js
• Develop RESTful APIs and Microservices-based applications
• Collaborate with cross-functional teams including UI/UX, DevOps, QA, and Product teams
• Write clean, efficient, and reusable code following best practices
• Perform code reviews and mentor junior developers
• Optimize applications for performance and scalability
• Participate in architectural discussions and technical decision-making
• Ensure application security, data protection, and compliance standards
• Troubleshoot, debug, and upgrade existing systems

Required Skills:

• 7+ years of experience in Full Stack development
• Strong hands-on expertise in Java (8/11/17)
• Proficiency in Spring Boot, Spring MVC, Spring Security
• Experience in Microservices architecture and RESTful API development
• Strong knowledge of React.js, JavaScript (ES6+), HTML5, CSS3
• Experience with state management tools (Redux/Context API)
• Hands-on experience with Hibernate/JPA
• Good understanding of SQL databases (MySQL/PostgreSQL/Oracle)
• Experience with Git, Maven/Gradle, and CI/CD pipelines
• Working knowledge of Docker/Kubernetes
• Exposure to Cloud platforms (AWS/Azure/GCP) preferred
• Strong problem-solving and analytical skills

• The ideal candidate will have experience in development teams that work on business facing transactional systems.
• They will have demonstrated the ability to manage people, make architectural decisions, understand business
• processes to deliver the cleanest solutions.
• Share responsibility for implementing the firms accounting platforms. Partner with 3 rd parties (like Consulting Firms)
• and develop technical specifications.
• Share responsibility for availability, scalability, performance and capacity from development through production
• for a critical strategic build of the new accounting platform
• Reduce errors on deployments, improve reliability, and increase speed of implementation through automation
• Continuously refine and improve our toolset to improve our data and persistence layers

• 7+ years of experience in IT including some experience in architecture roles
• Experience building multi-tier, scalable, fault-tolerant web applications
• Experience with platform integrations and designing service APIs
• Extensive Service-Oriented Architecture patterns and design knowledge and familiarity with cloud based services
• Expertise with identity management, authentication and information security best practices
• Expertise in working with complex cross-domain applications in a global organization across multiple time zones
• Enjoys a fast paced, high-intensity and complex environment, troubleshooting time sensitive critical issues and working with people
• Extensive experience with multi-tier transactional architecture and design
• Extensive experience in enterprise software development in Java and web development stacks (Angular, NodeJS, HTML & CSS)
• Experience with Sybase, Cassandra
• Event / Stream processing technologies
• Experience using Agile methodologies – previous experience working from a backlog, sprints, retrospectives etc.
• Passionate about test driven, clean code, automatically tested and continuous deployment
• Excellent analytical and problem-solving skills
• Strong interpersonal skills with ability to present and convey ideas
• Strong attention to detail; action-oriented attitude, and willingness to roll up sleeves
• Curious to explore emerging technologies and learn new things
• Use metrics to drive decision making
• Undergraduate degree in Computer Science or similar discipline, Masters degree preferred
• Experience in the financial services industry is preferred                                                                                                                         

• Work with development teams and product managers to ideate software solutions
• Design client-side and server-side architecture
• Build the front-end of applications through appealing visual design
• Develop and manage well-functioning databases and applications
• Write effective APIs
• Test software to ensure responsiveness and efficiency
• Troubleshoot, debug and upgrade software
• Create security and data protection settings
• Build features and applications with a mobile responsive design
• Write technical documentation
• Work with data scientists and analysts to improve software

• Proven experience as a Full Stack Developer or similar role
• Experience developing desktop and mobile applications
• Familiarity with common stacks
• Knowledge of multiple front-end languages and libraries (e.g. HTML/ CSS, JavaScript)
• Knowledge of multiple back-end languages (e.g. Javascript, PHP, WordPress) and JavaScript frameworks (e.g. Angular, React, Node.js)
• Familiarity with databases (e.g. MySQL, MongoDB), web servers (e.g. Apache)
• Excellent communication and teamwork skills
• Great attention to detail
• Organizational skills
• An analytical mind
• Degree in Computer Science, Statistics or relevant field

We are looking for highly motivated engineers with the following skillset-

• Engineering degree in Computer science or ECE or MCA is a must
• In-depth knowledge of PHP, HTML5, CSS, jQuery, JavaScript, AJAX
• Experience using PHP frameworks such as Laravel, Symfony, Zend, etc. - any 1 is required
• VueJS, AngularJS, ReactJS - knowledge of any 1 is required
• Between 1-5 years of work experience is required
• Very strong data structure and algorithm knowledge
• Ideal candidate would be a very strong developer with great coding skills
• Good English communication skills
• Willingness to work on multiple projects simultaneously
• Ability to work through ambiguous requirements and come up with a clear scope and problem statement
• If you have any live projects portfolio or GitHub handle please share them
• Office is in Fairlie place (Dalhousie), Kolkata 700 001

PHP, HTML, CSS, JAVASCRIPT, AJAX, REST API, JQUERY, POSTGRESQL, MYSQL, MVC FRAMEWORK.

Responsibilities:

• Design and build advanced applications
• Work with outside data sources and APIs
• Unit-test code for robustness, including edge cases, usability, and general reliability
• Work on bug fixing and improving application performance
• Continuously discover, evaluate, and implement new technologies to maximize development efficiency
• Building reusable code and libraries for future use
• Optimization of the application for maximum speed and scalability
• Implementation of security and data protection
• Able to understand and create Documentation according to Client requirement.

Requirements:

• Ability to write clean, commented and maintainable code.
• Proven track record in designing, architecting, developing enterprise class products and solutions.
• Good understanding of MVC frameworks.
• Good understanding of front-end technologies and platforms, such as JavaScript, HTML5, and CSS3.
• Desired experience in PHP.
• Understanding accessibility and security compliance.
• User authentication and authorization between multiple systems, servers, and environments.
• Integration of multiple data sources and databases into one system.
• Management of hosting environment, including database administration and scaling an application to support load changes.
• Data migration, transformation, and scripting.
• Understanding differences between multiple delivery platforms such as mobile vs desktop, and optimizing output to match the specific platform.
• Implementing automated testing platforms and unit tests.
• Proficient knowledge of a back-end programming language.
• Proficient understanding of code versioning tools, such as Git.
• Proficient understanding of OWASP security principles.
• Proper understanding of OOPS concepts.
• Creating database schemas that represent and support business processes.
• Understanding of startup culture.
• Good team player, Quick learner.