Jobs

We’re looking for a talented person to join our Development team. Your role will encompass a range of responsibilities, the main one being back-end development via Nest.js (Node.js).

You will work closely with a back-end developer with 5+ years of experience. We are ready to invest in you and bring you to the next level.

You will work closely with developers, designer, QA, and PM.

About you

At least 0.5 year of professional experience in Nest.js (Node.js).

Experience in teams of 2-7 people.

Understanding of project development life-cycle.

Understanding of Agile / Scrum.

Level of English — pre-intermediate.

Respect your and our time, and do not apply if you don't have business experience.

Hard Skills 

- TypeScript

- Node.js

- REST API

- Nest.js

- PostgreSQL

- MongoDB

- Understanding of principles of Functional Programming (FP) and Object-Oriented Programming (OOP)

- Dependency Injection (DI)

- Difference between SQL and NoSQL

- Writing clean, scalable code

following SOLID

- Experience with CI/CD

- Basic understanding of web security principles (OAuth, JWT, CORS)

Would Be a Plus:

- Jest

- AWS Lambda

- AWS SQS

- Infrastructure as Code (IaC)

- Ability to optimize applications for maximum speed and scalability

Responsibilities

Collaborate with the development team and customers.

Conduct research: user, products, tools (3rd parties); Analyze competitors and follow best practices of the product.

Set up and lead daily / weekly meetings.

Be responsible for the result.

Create user stories and keep project documentation updated.

Stay updated with the latest design trends, techniques, and technologies to ensure our products are always at the cutting edge of features and design.

What we offer 
22 days off and 12 sick days are paid by the company annually.
Paid national holidays.
Health Insurance

English classes.
GYM.

Teambuilding twice per year.
 

Please send your CV.

Sharkscode is looking for a Node.js Engineer to join our team!

To achieve the results you’ll need:
- 3+ years of commercial development experience with Node.js, Express.js;
- Deep knowledge of MongoDB, MySQL, PostgreSQL(optional), redis(optional);
- Experience with queues (rabbit);
- Experience in connecting third-party services, designing/writing API;
- Understanding of the specifics of working with distributed systems

Will be a plus:
- TypeScript, nest;
- Experience in covering code with autotests (Unit/Integration/E2E);
- Experience with high-load systems

How exactly you'll influence the company’s progress:
- Design and develop a product;
- Develop integrations with third-party financial and technical services;
- Design and develop public payment web services and internal microservices;
- Participate in decision-making on the feasibility of using certain technologies/practices at the platform level;
- Follow a development culture and share the knowledge already acquired with the team.

For comfortable and effective cooperation we offer the following:
- Opportunity to influence and feel your impact inside the company;
- Compensation that grows alongside your achievements;
- Paid vacation (17 days/year) and sick leaves;
- Medical insurance;
- Budget for conferences, seminars, and training that will help you grow as a professional;
- Free English courses;
- Flexible working hours;
- We have a cozy, modern office filled with everything you need in the historic center of Kyiv with free parking places.

Our stages: 

Interview with recruiter-> Tech Interview-> Offer

About the Role
 

We’re building an in-house batch payout and reconciliation platform for ERC-20 and TRC-20 tokens. You’ll own the end-to-end architecture - from hot-wallet key management and bulk on-chain transfers to monthly SLA reporting - supporting up to 10,000 concurrent transactions.

Key Responsibilities:

- Architect and build a high-throughput batch payout engine in Node.js, handling ERC-20 & TRC-20 token transfers

- Integrate with self-custodied hot wallets; securely manage private keys (AWS KMS, HashiCorp Vault, HSM, etc.)

- Implement nonce management, gas optimization (EIP-1559), and on-chain batch-transfer contracts

- Develop reconciliation logic using both on-chain data and off-chain data from CEXs/DEXs and Oracles

- Design retry strategies, error handling, and idempotent workflows for failed or reverted transactions

- Monitor system health, log all activities, and produce monthly SLA reports, tracking success rates, confirmation times, and uptime

Required Qualifications:

- 5+ years professional Node.js experience

- Deep familiarity with blockchain protocols - ERC-20 & TRC-20 standards, gas/bandwidth/resource models

- Hands-on experience with web3.js, ethers.js, tronweb, and CCXT

- Proven track record designing high-throughput systems with precise nonce and concurrency control

- Solid understanding of cryptographic key management best practices (hot wallets, KMS/Vault, HSM, multi-sig)

- Ability to troubleshoot complex blockchain issues - gas volatility, reorgs, token approvals, API rate limits, TRON resource constraints.

Mindset & Communication:

- Ownership mentality: you balance urgent deliverables with long-term architectural vision

- Organized and reliable: you prioritize critical tasks without sacrificing code quality

- Research-oriented approach: you evaluate tools and patterns, but focus on what works in practice

Nice-to-Have

- Experience writing or integrating batch-transfer smart contracts in a Node.js environment (e.g. OpenZeppelin MultiSend)

- Knowledge of The Graph subgraphs for DEX data analytics

- Prior work in crypto exchange integrations or fintech reconciliation systems

What is the purpose of this position?
We are looking for an experienced developer (4+ years of commercial experience) to strengthen our team. Currently, potential clients make many requests, so we want to engage a new specialist on board and provide fast staffing. As far as we use different sources for clients attraction, on some project may be used time-tracking. Please pay your attention to this. 

Qualification you`ll need to bring:
— 3+ years of commercial experience with Node.js is a must
— Experience and understanding of core concepts of Javascript
— ​​2+ years of hands-on experience with TypeScript
— Excellent knowledge of the development of scalable and highly available RESTful APIs using Node.js
— Understanding of Single Sign-on and token-based authentication REST, JWT, oAuth
— The ability to use version control systems, in particular — Git
— ​​Familiarity with modern and upcoming standards
— Intermediate+ English level at least
— Ability to work self-managing and autonomously

It will be a plus
— Practical experience with complex mongoose aggregations
— Basic knowledge of three-layer architecture (transport layer, business logic layer, data layer)
— Basic knowledge of patterns (GoF band, SOLID, GRASP)
— Experience with unit and Integration testing with Mocha, Chai, Jest
— Experience in a frontend development using React

In this role, you will be in charge of:
— Developing front-end part of a project
— Creating responsive and adapting to running on a mobile device UI 
— Writing unit/integration tests
— Setup task runners and build tools
— Collaboration with a cross-functional team 

We offer:
— Remote Work Environment. Work from anywhere and be part of a geographically diverse team
— Stay Ahead of the Curve. Work with cutting-edge technologies
— Possibility of payment by PE accaunt, Payoneer or Wise
— Bonus & Referral system
— Paid 16 vacations and 14 sick leaves per year (after transferring to full-time cooperation)
— Flexible hours
— Compensation program for purchasing new laptops
— Paid professional certifications & educational courses
— Paid English classes
— Friendly atmosphere with quarterly team buildings
— No bureaucracy

Ready to try your hand? Do not pull the cat’s tail and send your CV without a doubt!

For those candidates who don’t get any feedback after applying: We are so thankful for your time and attention to our vacancy! However, sometimes we get more than 100 CVs at once, and it would take several days to answer them all. That’s why we reach out only to relevant candidates. We hope for your understanding.

📅 Full-time or Part-time

What You Bring

• 4+ years of software development experience
• Strong hands-on experience with Solidity and Smart Contracts
• Proficient in Node.js, TypeScript, and React
• Experience with backend frameworks like NestJS
• Familiarity with mass payment solutions using Smart Contracts
• Understanding of blockchain architecture, DApps, and cryptographic principles
• Knowledge of asynchronous programming and event-driven design
• Relational databases and query optimization: MySQL/PostgreSQL
• Strong grasp of software design patterns and clean architecture
• Comfortable writing tests and working in CI/CD environments
• Understand Ukrainian and is a proactive communicator

What You’ll Be Doing

• Develop, integrate, and maintain Smart Contracts in Solidity: ERC-20, TRC
• Design and build full-stack applications using Node.js, TypeScript, React, and NestJS
• Architect and implement secure, transparent blockchain-based features and workflows
• Collaborate with the Architect, PM, and Designer to ship high-quality features
• Optimize backend and database performance: MySQL/PostgreSQL
• Ensure code quality with robust unit, integration, and E2E tests
• Manage deployments and infrastructure: Docker, CI/CD, etc.
• Solve complex problems independently and proactively
• Document technical processes and systems

What You’ll Get

• Competitive compensation reflecting your skills and experience
• Freedom to experiment with new tools and frameworks
• Ongoing learning support — courses and certifications
• Paid time off: vacation, holidays, and sick leave
• A collaborative team that values your input
• Career growth opportunities as we expand
• Flexible hours & remote-first culture
• Free English lessons

About the Product: You will develop a blockchain-powered platform where every interaction is verifiable, secure, and transparent. Smart Contracts are at the core — driving mass payment systems, ensuring fairness, and enabling real-time, trustless functionality. If you’re excited by Web3, transparency, and elegant engineering, this project is for you!

MustardHub is a B2B SaaS startup in the employee benefits, rewards & recognition space.

We've built our MVP in 2023, confirmed the hypothesis with several large customers, and are now underway building the v1 from ground-up.

This position is for an experienced, autonomous back-end developer. We're a very small team, led by the two co-founders, with an 2 FE & 2 BE devs, BA/PM, QA, and a talented designer. 

About You:

- 5-7+ years experience building large, complicated codebases

- You've worked on large B2B or B2C SaaS products

- You understand what working in early-stage startups is like

- Your English is good enough to have conversations with patient fluent speakers

- You are EXCITED about being on the ground floor of a startup that changes how companies approach employee rewards & benefits management

- You're using modern AI coding tools like Cursor, v0, Claude Code and/or others to increase your output 2-4x.

Our Tech Stack:

- Typescript: React, Nest, GraphQL/Apollo, Postgres. 

We're based in Austin, TX (US) but the development team is expected to be all remote. The other team members are in Ukraine and the rest of Eastern Europe. You're expected to have at least a few hours overlap with the CDT timezone each day.

We’re seeking a Senior Node.js Developer with experience in external API integrations and REST APIs (especially AdTech and messaging APIs), which is essential for this role.

 

About the project:
An AI-driven platform designed to transform voice and text communications for business users, particularly in call center environments. It automates customer interactions, significantly reducing operational costs by up to 65% and increasing ROI by up to five times.
Project stage: Live product with active clients; currently scaling the integrations layer.
Location & Timezone: USA-based; working hours until 8–9 p.m. Kyiv time.

Project advantages:
— High-impact, autonomous role: own the entire integration layer
— AI-powered product solving real-world business needs (proven ROI)
— Modern stack: messaging, AdTech, CRM platforms
— Fast-paced US startup with long-term potential
— Strategic hire as part of the company's scaling efforts


Responsibilities:
— Integrate messaging platforms (WhatsApp, Facebook Messenger, Telegram)
— Integrate AdTech platforms (Meta Ads, Google Ads, Microsoft Ads)
— Work with the existing Node.js API Gateway and MongoDB layer
— Build integrations with CRM and automation platforms (Salesforce, HubSpot, Zapier, etc.)


Requirements:
— 5+ years of experience with Node.js
— 2+ years with TypeScript
— Experience with MongoDB
— Strong experience with external API integrations and REST APIs (AdTech and messaging APIs)
— Advanced level of English

 

If you’re interested in this opportunity, please let us know!

About Us

We are a leading Israeli IT company with 15 years of market experience and 8 years in Ukraine. Officially registered in Ukraine, Israel, and Estonia, we employ over 100 professionals worldwide. Specializing in successful startup collaboration, we offer services across e-commerce, Fintech, logistics, and healthcare.
 

Our client is a technology company focused on supply chain management and procurement optimization. Сlient`s product simplifies purchasing processes by leveraging modern technology, helping businesses automate supply chains and reduce costs.

We are looking for a highly skilled and passionate Web Scraping Engineer​​​ with strong Puppeteer expertise and a passion for startups to join our team!
 

Key Requirements:

🔹 4+ years of experience with the Node.js programming language;
🔹 Proficiency in Puppeteer library — must;
🔹 Strong knowledge of the Web scraping — must;
🔹 Solid experience with JavaScript programming language;
🔹 Debugging, problem-solving, and performance optimization skills;
🔹 English – Upper-Intermediate or higher.
 

What you will do:

🔹Developing and maintaining server-side applications using Node.js;
🔹Implementing web scraping solutions utilizing the Puppeteer library to extract data from web pages;
🔹Analyzing requirements to design and implement new features related to data extraction;
🔹Testing and debugging applications to ensure reliability and efficiency in web scraping processes;
🔹Writing clean, efficient, and secure code, adhering to best practices in software development;
🔹Staying updated with the latest web scraping techniques and tools to enhance data collection capabilities.
 

Why Join Us?

🔹 Be part of a friendly international team, working together on interesting global projects;
🔹 Enjoy many chances to grow, learn from mentors, and work on projects that make a real difference;
🔹 Join a team that loves fresh ideas and supports creativity and new solutions;
🔹 Work closely with clients, building great communication skills and learning directly from their needs;
🔹 Thrive in a workplace that values your needs, offering flexibility and a good balance between work and life.

Job Description

We are looking for an experienced Backend Developer (Node.js/NestJS) to join our team to develop and maintain the backend of our company’s projects. You will work on building web services and APIs, using a modern tech stack and cloud infrastructure, and you’ll also be involved in communication with clients at every stage of the project.

If you’re confident with Node.js and TypeScript, know how to design scalable backend architecture, and are ready to take ownership of your work - this role is for you. Expect engaging challenges (including work on AI/chatbot projects), a flexible remote work setup, and a supportive team of professionals.

 

Responsibilities

• Backend Development: Build new functional modules and APIs using Node.js/NestJS, and maintain/refactor existing code.
• System Architecture: Participate in system design and choose optimal solutions and technologies for new features and projects.
• Database Work: Design data schemas, optimize queries, and ensure efficient interaction with SQL/NoSQL databases.
• Estimations & Client Communication: Estimate task complexity and participate in sprint planning. Communicate directly with clients to clarify requirements, discuss technical decisions, and demonstrate results.
• Code Quality: Write unit and integration tests, participate in code reviews. Detect and fix bugs quickly while improving performance and security.
• Deployment & Support: Participate in CI/CD and release processes. Set up environments, deploy applications to the cloud (GCP/AWS) or company servers, and ensure service uptime and monitoring.

Requirements

• Commercial Experience: At least 2 years of experience developing backend systems with Node.js.
• JavaScript/TypeScript: Excellent knowledge of JavaScript (ES6+) and confident production-level experience with TypeScript.
• Node.js & Frameworks: Strong hands-on experience with Node.js. Proven experience with NestJS in real projects. Familiarity with other Node.js frameworks like Express or Fastify and solid understanding of backend design patterns.
• Databases: Excellent knowledge of SQL and experience with relational databases (especially PostgreSQL). Ability to design efficient DB schemas and optimize queries. Experience with NoSQL databases such as MongoDB.
• ORM/ODM: Experience with tools like Sequelize, TypeORM, or similar for interacting with databases.
• Caching & Queues: Experience using Redis for caching, task queues, or session storage. Understanding when and how to apply caching while maintaining data consistency.
• Containerization & DevOps: Confident in working with Docker and Docker Compose. Understanding of CI/CD processes and deployment tools (e.g., GitLab CI, GitHub Actions, Jenkins). Experience setting up and maintaining environments. (DevOps experience is a plus.)
• Cloud & Serverless: Experience with cloud platforms, particularly Google Cloud Platform (GCP) — including Firebase (Auth, Firestore). Understanding serverless architecture principles and experience with serverless functions (e.g., AWS Lambda or similar).
• API & Integrations: Skilled in building RESTful APIs (GraphQL is a plus). Knowledge of authentication/authorization (JWT, OAuth2, etc.) and experience integrating third-party services and APIs.
• AI & Chatbots: Practical experience in developing chatbots or AI agents. Participation in projects using Google Vertex AI and/or OpenAI API is a strong advantage.
• Development Tools & Workflow: Proficient with Git. Experience working in Agile teams, participating in code reviews, and writing clean documentation.

• Soft Skills: Analytical mindset, responsibility, and independence. Ability to communicate clearly with both team members and clients, and to explain technical decisions in simple terms.

  Upper-Intermediate or higher English is required for meetings and client communication.

Nice to Have

• Experience with Python development (knowledge of Django or Flask is a plus).
• Knowledge of other backend languages/environments (e.g., PHP, Go, Java) to show breadth of expertise.
• Experience designing microservices architectures, understanding SOA principles. Familiarity with message brokers (RabbitMQ, Apache Kafka) and stream processing.
• Familiarity with gRPC, GraphQL, and API design using those technologies.
• Understanding of high-load system design principles and performance optimization techniques.
• Experience with container orchestration systems (Docker Swarm, Kubernetes) and infrastructure as code tools (Terraform, Ansible).

What We Offer

• Remote Work: Work from anywhere. The only requirement is a stable internet connection and availability during agreed hours. Flexible schedule focused on results, with occasional calls with the team and clients.
• Competitive Compensation: Salary from $1000 to $2000 USD/month (net), with growth opportunities based on your skills and contribution. Final terms are discussed individually after the interview.
• Interesting Projects: You’ll work on a variety of client products — from web platforms to AI-powered chatbots — with real impact on tech decisions and room for creativity.
• Professional Development: A team of experienced developers, regular code reviews, and knowledge sharing. We support professional growth by covering expenses for relevant courses, books, and certifications (upon agreement).
• Team & Culture: A small, tight-knit team that values direct communication, initiative, and responsibility. Minimum bureaucracy, maximum openness to your ideas.
• Long-Term Collaboration: Full-time employment with long-term prospects. We invest in growing in-house experts — for successful team members we offer expanded responsibilities, promotion opportunities, and regular compensation reviews.

If you see yourself in the description above and are ready to grow with us - send us your resume! We’d be happy to get to know you and discuss the details of our potential collaboration.

Objective:

We are looking for an experienced Senior JavaScript Developer. You'll be solving very relatable user problems and helping build a truly outstanding product experience for travellers worldwide while they're searching, comparing, and booking their best journey.
Features will be shipped across all front-end platforms with the goal of monetizing user traffic while delivering an exceptional user experience.

Our platform is built on Java, TypeScript,  Node.js, React.js, React Native, Spring, Spring Boot, Couchbase, BigQuery, Docker, Kubernetes, Graphite, Grafana, Kibana and GraphQL

Responsibilities:

• Develop robust frontend solutions using modern technologies, building components that are used across all front-end platforms (mobile and web apps).
• Collaborate with your team to quickly test ideas with users, analyze results, and iterate to improve the product.
• Explore and evaluate new languages, libraries, and frameworks to foster continuous innovation. Share best practices and contribute to setting technical standards across teams.
• Create highly reusable frontend components that can be dynamically integrated into any React-based frontend.
• Leverage your engineering expertise to automate processes and support the team in making informed technical decisions.
   

Qualifications:

• 5+ years of professional experience in JavaScript development, with 4+  years on Node.js as well
• You have improved performance and analysed bottlenecks in production systems through benchmarks and stress tests. You are no stranger to profiling a front-end.
• Strong understanding of asynchronous programming and event-driven architectures.
• Experienced in tackling complex, multi-domain problems by analyzing requirements, designing and building modular solutions, and delivering them through an MVP-first, value-driven, and iterative approach.
• Familiarity with version control systems like Git.
• Excellent problem-solving skills and attention to detail.
   

English - upper- intermediate or higher.

Recruitment process: 
HR call
Technical
Client:
Pre-screen interview
Test Task
Tech screen and PM Interview
Technical client Interview
Final Business Interview
 

• Project Description:

  One of the biggest UK rail network companies operating with rail infrastructure and asset management has a need to develop and support enterprise-level information systems.
  
  Align the data science initiatives with the overall business goals. This could range from improving customer satisfaction, enhancing operational efficiency, to driving sales growth.

• Responsibilities:

  Software development
  Unit/integration testing
  Azure environment configuration
  Customer communications

• Mandatory Skills Description:

  3+ years of experience
  Azure App service implementation and deployment.
  Fastapi and asyncio (asynchronous programming)
  Auth (OAuth, JWT, Microsoft authentication flow).
  Docs (OpenAPI, Swagger).
  SQL Alchemy or alternative DB integration libraries.
  Python/Pytest
  JS/Node
  SQL
  GIT and collaborative workflows
  Bash, shell scripting.

• Nice-to-Have Skills Description:

  Azure Container Management (docker, container registries, CI/CD to app services).
  CI/CD approaches
  Security across Azure (key vault, app service configuration, auth).
  Virtual Machine deployment
  Familiarity with storage accounts and their components

We’re seeking a Frontend Engineer (Vue.js) with Nuxt.js experience, which is required for this role.


About the project:
A Paris-based startup has developed a generative AI platform designed to streamline mergers and acquisitions (M&A) processes. The solution offers a secure digital workspace where users can upload deal documents, enabling AI agents to extract insights, answer questions, and automate repetitive tasks. By transforming complex information into actionable intelligence, the platform allows analysts and consultants to make faster, more informed decisions throughout the deal lifecycle. With a strong focus on data security, all documents are processed within the client’s IT infrastructure, ensuring full confidentiality and compliance.
Project location and timezone: France (CEST/CET)

Project advantages:
— Small team with fast decision-making and tight collaboration
— Closely working with founders who have a technical background and a clear product vision, making communication efficient and execution focused
— Modern tech stack — as the project is 1 year old, and just recently switched to Nuxt.js, so you get to shape the architecture and make key technical decisions early on
— Full technical ownership within front-end + real influence on product success

Responsibilities:
— Migrate the existing front-end app from Vue 3 to Nuxt 3
— Implement detailed change tracking
— Refactor API-calling functionality
— Fix non-clickable page shortcuts
— Disable tooltips from web sources

Requirements:
— 4+ years of experience with Vue.js
— 4+ years of experience with TypeScript
— 2+ years of experience with Nuxt.js
— Any experience with Tailwind CSS
— Upper-Intermediate or higher level of English
 

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 seeking a skilled Middle Nest.js Developer to join our core backend team. You will step into a project with a well-structured, high-quality codebase and play a key role in implementing complex business logic within our microservices architecture.

Your primary focus will be the automation of trading operations on Centralized Exchanges (CEX). You will be responsible for translating trading strategies into robust, high-performance code, building out the logic for working with orders, and ensuring seamless, low-latency integration with various exchange APIs. This is a hands-on role where you will be writing the code that powers our automated trading bots.

Key Responsibilities:

1. Develop and Maintain Backend Services with Nest.js and TypeScript. Your core task will be to write clean, efficient, and reliable code within our existing microservices architecture, focusing on the implementation of trading-related features.
2. Work with Databases using Prisma ORM. You will be responsible for writing queries, managing data, and working with schemas in PostgreSQL, using Prisma as the primary tool for database interaction.
3. Work with a Large, Existing Codebase. You will need to quickly get up to speed with our current architecture, understand how the services interact, and continue development while adhering to our established quality standards.
4. Integrate with Third-Party CEX APIs (REST & WebSocket). You will implement the logic to connect with centralized exchanges to fetch order books, manage trades, and handle real-time market data.
5. Implement Trading Logic and Automation. You will translate trading strategies and business requirements into functional code, building out the core logic for our Order Service and automating actions with exchanges.
6. Collaborate with the Team. You will work closely with the Backend Lead, other developers, and the frontend team to define and ship features in a fast-paced environment.

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, specifically PostgreSQL, and practical skills using Prisma ORM.
• Hands on using CEX DEX
• Experience integrating with complex third-party APIs.
• Experience with message broker technologies (we use BullMQ).
• Proficiency with Git and modern development workflows.

• A proactive mindset with strong problem-solving skills.

   

How to know if you are the right fit:

• You understand the differences between a CEX (Centralized Exchange) and a DEX (Decentralized Exchange) and have hands-on experience using both.
• You are comfortable working within an existing microservices architecture and can quickly adapt to a large codebase.
• Will be a big plus if you have practical experience building trading bots or other systems that automate actions with exchange APIs.
• You understand the difference between a Limit Order and a Market Order and understand what is Order Book and hot it works.
• You have a strong interest in the Crypto/FinTech space and are eager to work on a high-performance trading platform.

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.

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.

MustardHub is a B2B SaaS startup in the employee benefits, rewards & recognition space.

We've built our MVP in 2023, confirmed the hypothesis with several large customers, and are now underway building the v1 from ground-up.

This position is for an experienced, autonomous back-end developer. We're a very small team, led by the two co-founders, with an 2 FE & 2 BE devs, BA/PM, QA, and a talented designer. 

About You:

- 5-7+ years experience building large, complicated codebases

- You've worked on large B2B or B2C SaaS products

- You understand what working in early-stage startups is like

- Your English is good enough to have conversations with patient fluent speakers

- You are EXCITED about being on the ground floor of a startup that changes how companies approach employee rewards & benefits management

- You're using modern AI coding tools like Cursor, v0, Claude Code and/or others to increase your output 2-4x.

Our Tech Stack:

- Typescript: React, Nest, GraphQL/Apollo, Postgres. 

We're based in Austin, TX (US) but the development team is expected to be all remote. The other team members are in Ukraine and the rest of Eastern Europe. You're expected to have at least a few hours overlap with the CDT timezone each day.