Java Backend Engineer – P2P Marketplace

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. 

One More Game is looking for a Senior Blockchain Engineer to help build secure and scalable blockchain systems for our web3 gaming products. This role is focused on smart contract development, blockchain integration, and technical problem-solving in a remote, fast-moving environment. You will work closely with our engineering and product teams to design, build, test, and maintain blockchain features that support real users and game economies. ResponsibilitiesDesign, develop, test, and deploy smart contracts.Build secure and efficient blockchain integrations for web3 applications.Work with product and engineering teams to implement on-chain features.Review contract logic for performance, reliability, and security.Write clear technical documentation and testing coverage.Support debugging, maintenance, and upgrades for deployed contracts. Requirements3+ years of professional software engineering experience.Strong experience with Solidity and EVM-compatible blockchains.Hands-on experience with smart contract testing and deployment tools such as Foundry or Hardhat.Good understanding of blockchain architecture, wallets, transactions, and contract interactions.Experience building production blockchain applications.Strong communication skills and ability to work remotely. Preferred QualificationsExperience with GameFi, NFTs, DeFi, or Layer 2 solutions.Familiarity with backend or frontend integration for blockchain apps.Experience working in a remote startup environment. What to SubmitPlease include:GitHub profile.LinkedIn profile.A brief summary of your most relevant blockchain project.A short explanation of your role and technical contribution. About One More GameOne More Game is a US-based, fully remote company building blockchain-powered gaming infrastructure and digital experiences.

The project is being developed around a Web3 trading infrastructure platform. As part of our long-term vision, the UK team at Iress is building a scalable, secure, and production-ready platform for trading, staking, and DeFi functionality. To support this effort, we are looking for experienced blockchain developers who can contribute to smart contract development, architecture, security, and overall platform implementation. We are currently in the team-building phase and identifying developers whose experience aligns with the technical requirements of the project. Selected candidates will be invited to discuss the project roadmap, responsibilities, and collaboration model with the UK technical leadership team.

 
 
we’re looking for a senior blockchain engineer to build low-latency execution infrastructure around hyperevm and hyperliquid-related trading systems.
 
this is not a frontend or dapp role. the focus is on real-time execution systems, chain-native infrastructure, and market-aware backend engineering where latency, ordering, and state correctness directly impact execution outcomes.
 
you will work on systems that operate under noisy, adversarial, and highly dynamic conditions, including delayed or missing websocket events, rpc inconsistencies, transaction lifecycle complexity, state desynchronization, retries, and recovery logic.
 
core responsibilities include building and maintaining realtime blockchain data pipelines, websocket and rpc streaming systems, execution orchestration layers, liquidity-aware routing logic, transaction lifecycle management, and integration with orderbook and market data systems.
 
we are specifically looking for engineers who think in systems rather than features. meaning understanding how data flows through pipelines, how state evolves over time, how failures propagate, and how to design systems that recover automatically without manual intervention.
 
areas of work include:
 
- realtime blockchain data ingestion
- mempool-aware execution flows
- transaction lifecycle handling
- execution sequencing and routing
- websocket and rpc infrastructure
- state synchronization systems
- liquidity and orderbook integration
- performance and latency optimization
 
you should be comfortable working with distributed systems, asynchronous event processing, and latency-sensitive backend architectures.
 
strong experience in one or more of the following areas is highly relevant:
 
- exchange infrastructure
- trading systems
- execution engines
- blockchain indexers
- realtime event systems
- arbitrage systems
- rpc/node infrastructure
- defi backend systems
- low-latency backend engineering
 
preferred technical stack:
 
- typescript / node.js
- go
- rust
- python
- postgres
- clickhouse
- redis
- kafka or similar messaging systems
- docker
- linux environments
- evm rpc internals
- websocket infrastructure
 
ecosystem familiarity:
 
- ethereum, arbitrum, base, optimism, bsc
- hyperliquid / hyperevm
- foundry
- ethers.js / viem
- geth / erigon / nethermind
- dex and amm mechanics
- liquidity math, slippage, gas strategy, routing logic
 
this role is not suitable for:
 
- frontend-only developers
- nft or basic dapp experience only
- tutorial-level web3 developers
- candidates without production systems experience
 
we value engineers who have built real systems where correctness, latency, and reliability matter under load. we care less about buzzwords and more about concrete systems you have personally built and operated.
 
ideal candidates can clearly explain:
 
- system architecture decisions
- bottlenecks and tradeoffs
- failure modes and recovery strategies
- latency considerations in real systems
- production debugging experience
 
working style:
 
- remote
- async-first
- low bureaucracy
- high ownership
- engineering-driven team
- direct technical communication
 
we strongly prefer practical engineering depth over polished presentation. if you have built or worked on systems involving realtime data, trading infrastructure, blockchain execution, or latency-sensitive backend systems, please include details of those systems when applying.