Data Engineer (Middle+/Senior)

Worklo is building the future of professional services automation by combining our core PSA platform with a blockchain-powered salary distribution system. The platform automates compensation based on project data, time entries, role assignments, milestones, and secure on-chain payroll execution.
We are looking for a highly capable Full Stack / Blockchain Engineer who can own both SaaS product development and blockchain infrastructure. This is a high-ownership role where you will help shape Worklo PSA and our blockchain payroll architecture from the ground up.
Key Responsibilities
* Build full-stack product features using Next.js, TypeScript, Node.js/Express, Supabase, PostgreSQL, React, shadcn/ui, and Tailwind CSS
* Design secure APIs, database schemas, authentication flows, and Supabase RLS policies
* Develop Solidity smart contracts for salary calculation and automated payroll distribution
* Build blockchain integrations for wallet registry, MetaMask/WalletConnect, payroll execution, and event syncing
* Deploy and manage smart contracts on Polygon or other EVM-compatible networks
* Implement dashboards for payroll visibility, wallet management, and transaction history
* Write tests for smart contracts using Hardhat, Foundry, or similar tools
* Improve performance, security, observability, and overall system architecture
Requirements
* 5+ years of full-stack software development experience
* 5+ years of blockchain development experience with deployed smart contracts
* Strong skills in TypeScript, Node.js, React, Next.js, PostgreSQL, and REST APIs
* Strong Solidity knowledge, including access control, reentrancy protection, gas optimization, and upgradeability
* Experience with ethers.js, viem, ERC-20 tokens, stablecoins, and EVM-compatible networks
* Ability to work independently in a remote-first, async startup environment
Nice to Have
* Experience with Supabase, Next.js App Router, React Server Components, Foundry, Hardhat, OpenZeppelin, The Graph, DeFi systems, multi-sig wallets, or multi-tenant SaaS platforms

The Role
We are hiring a Senior Blockchain Developer to design and build smart contract systems across multiple client and internal projects.
You will work on a variety of blockchain applications - from DeFi protocols to tokenized systems and Web3 platforms - ensuring high standards in security, scalability, and architecture.
This is a senior-level, hands-on role with exposure to multiple products and industries.
What You’ll Do
Design, develop, and deploy smart contracts using Solidity
Implement token standards (ERC-20, ERC-721, ERC-1155) and custom logic
Build and maintain contract architectures across multiple projects
Ensure security, audit readiness, and upgradeability
Optimize gas usage and performance
Collaborate with backend and frontend teams for integrations
Participate in code reviews and technical decision-making
Contribute to documentation and internal best practices
What We’re Looking For
4+ years of experience in blockchain / smart contract development
Strong expertise in Solidity and EVM-based ecosystems
Experience with Ethereum and L2s (Polygon, Arbitrum, Optimism)
Solid understanding of smart contract security and vulnerabilities
Experience with Hardhat, Foundry, or similar frameworks
Strong software engineering fundamentals (testing, Git, CI/CD)
Ability to work across multiple projects and adapt quickly
Nice to Have
Experience with DeFi protocols, staking, or token economies
Experience working with auditors or security reviews
Familiarity with upgradeable contracts (proxy patterns)
Backend experience (Node.js / TypeScript)
Experience in client-facing or consulting environments
Tech Stack
Solidity · Ethereum · Polygon · Arbitrum
Hardhat / Foundry · Node.js · TypeScript
React · ethers.js · IPFS
Why Join
Work across a diverse portfolio of blockchain projects
Exposure to both client work and internal ventures
Opportunity to influence architecture and technical direction
Collaborative, globally distributed team
Fast-paced environment with continuous learning
What Success Looks Like
Secure, production-ready smart contracts delivered across projects
Successful audits with minimal critical issues
Scalable and reusable contract architectures
Strong collaboration with cross-functional teams
Consistent delivery across multiple initiatives
How to Apply
Please submit:
Resume or LinkedIn
GitHub profile (required)
Examples of smart contracts or blockchain project
Apply Directly:
https://rwahubassets.com/
Applications & Inquiries:
support@rwahubassets.com
Equal Opportunity
We value diversity and are committed to building an inclusive environment.

Currently, our team is working on crypto betting website development that is for old customer who lives in Luxembourg.
There are 7 developers in our team right now.
We just started Front-UI development but our current progress is getting slowly so we are looking for developers who has experience in Blockchain development.
For this project, you need to have proven experience in React, TypeScript, Node.js and Web3.js for Front-end Development or Solidity for Smart Contracts Development.
If you are interested, then we can discuss more details.
Thanks Regards. 

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I am looking for a developer who has much experience in Mobile application development.
But specially, candidate should be native in English.
Team communication is very important.
Please bid US only
Thank you