Middle FullStack Engineer

Hola Tech., JSC is hiring a Middle FullStack Engineer to join their Blockchain & AI team. You will develop and maintain backend services and frontend features using NodeJS/NestJS, ReactJS, PostgreSQL, Redis, and Docker/Kubernetes in a full-time role based in Hanoi.

What you'll do

• Develop and maintain backend services and frontend features according to agreed design and specifications
• Implement REST APIs, integrate frontend with backend, and write unit tests for your work
• Handle blockchain-level feature tasks including calling contracts, reading and displaying on-chain data, managing wallet connection flows, and tracking transaction status under senior guidance
• Contribute to modules within the microservices architecture
• Fix bugs, resolve assigned issues, and support basic troubleshooting investigations
• Participate in code reviews, incorporate feedback, and apply the team's coding standards
• Document your work and update progress regularly

What you bring

• 3-4 years of web development experience
• Strong JavaScript/TypeScript skills with hands-on experience using NodeJS Express and ReactJS
• Practical blockchain experience: you have written code that interacts with smart contracts or on-chain data
• Solid understanding of relational databases (PostgreSQL) and ability to write queries
• Understanding of and commitment to Clean Code principles and basic SOLID principles
• Knowledge of design patterns and system design, with the ability to build projects from scratch
• Ability to design and use REST APIs, with foundational understanding of HTTP, JWT, and OAuth authentication
• Grasp of core blockchain concepts: transactions, gas, wallets/private keys, ABI, and event logs
• Experience with at least one on-chain interaction library such as ethers.js, web3.js, viem, or equivalent
• Familiarity with Git workflows and Docker at a level where you can run local development environments
• English reading comprehension of technical documentation
• Ability to work in Agile/Scrum environments

Nice to have

• Experience with Redis, message queues, or caching
• Experience using AI coding tools such as Claude or Codex with the ability to verify outputs rather than copy blindly

What we offer

• Salary up to 30M VND gross, negotiable based on skills and experience
• 2-month probation period at 100% salary
• Performance review twice per year based on work effectiveness and company performance
• Working hours: 09:00-18:00 Monday to Friday with 1.5 hours lunch break from 12:00-13:30
• Performance bonuses, project bonuses, 13th-month salary, and holiday bonuses according to company policy
• Two company trips per year, company birthday celebrations, year-end party, and other events
• Company-provided monitors and necessary equipment; you bring your own laptop
• Professional development opportunities in the Blockchain & AI field

About Hola Tech., JSC

Hola Tech., JSC is a blockchain and AI-focused technology company based in Hanoi, Vietnam, working on innovative projects in the decentralized technology space.