Middle Nest.js Developer (DEX, Wallets) to $2500 Offline

Location: Remote

Job Type: Project Contract 4 months

Start Date: ASAP (As Soon As Possible)

Please note: This is a contract position with an immediate start date. We are looking for a candidate who can quickly integrate into our team and begin contributing from day one.

About Us

TechChain Solutions is a dynamic technology firm focused on building high-performance financial platforms. We create sophisticated tools that empower users to navigate complex market environments with speed and reliability. Our team is driven by innovation, and we are currently developing a new trading platform from the ground up.

The Role

We are looking for a skilled Middle Nest.js Developer with a strong practical background in blockchain and Web3 technologies. You will join our team to focus on the implementation and maintenance of our DEX-focused services, working primarily on the logic involving wallets, on-chain transactions, and smart contract interactions, which is the core of our platform's on-chain operations.

Your main tasks will be to develop microservices and work within a large codebase, writing the code that interacts directly with multiple blockchains (EVM, Solana, TON), managing secure transaction signing, and implementing logic for DEX trading strategies. This is a hands-on role where you will work with libraries like Ethers.js, solana/web3.js, and ton/ton to build reliable and secure on-chain solutions within our existing Nest.js microservices architecture.

Key Responsibilities:

1. Develop and Maintain Backend Services with Nest.js. Your primary responsibility will be to write clean, secure, and efficient TypeScript code, focusing on on-chain interactions, wallet management, and transaction processing.
2. Work with Databases using Prisma ORM. You will manage data related to wallets, groups, and transactions in our PostgreSQL database using Prisma.
3. Work with a Large, Existing Codebase. You need to be able to quickly understand our current microservices architecture and contribute high-quality code that aligns with our standards.
4. Implement DEX-related Logic. You will write code that interacts with Automated Market Maker (AMM) protocols (like Uniswap), handles token transfers (ERC-20 & SPL), and manages the lifecycle of on-chain transactions.
5. Contribute to our Asynchronous Task System. You will work with our existing transaction processing system built on BullMQ and Redis to ensure reliable and scalable on-chain operations.

Required Qualifications & Skills (Must-Haves):

• 2.5+ years of professional experience in backend development with Node.js and TypeScript.
• Strong, hands-on experience building applications with the Nest.js framework.
• Solid experience with relational databases (PostgreSQL) and practical skills using Prisma ORM.
• Deep, practical experience with Web3 libraries for at least one of the following blockchains: EVM-compatible chains (using ethers.js/web3.js), Solana, or TON.
• Solid understanding of blockchain fundamentals: transactions, the mempool, gas, blocks, and smart contracts.
• Hands-on experience interacting with ERC-20 and/or SPL token contracts.

• A proactive and security-first mindset, especially when dealing with private keys and on-chain funds.

   

How to know if you are the right fit:

• You understand what GAS is, why it's needed, what is difference between sending ETH and ERC20 tokens. You are familiar with the concept of a dedicated "gas wallet".
• You know the DIfference betwen DEX and CEX. You understand what is Automated Market Maker (AMM) on a DEX works and can explain its key differences from a traditional Central Limit Order Book (CLOB) found on CEXs.
• You have practical experience sending tokens between wallets and calling methods on smart contracts.
• You are excited by the challenge of building a secure and scalable system that manages a large number of wallets and performs on-chain actions.

What We Offer:

- Competitive compensation.

- A fully remote and flexible work environment.

- The opportunity to work on a high-impact, greenfield project with a modern tech stack.

- A focused and collaborative team culture.