Senior Software Engineer - Special Projects
Circle is a cutting-edge fintech company operating within the realm of the evolving internet of money. Our innovative approach enables the seamless transfer of value globally, promptly, and affordably compared to traditional settlement systems. Through our groundbreaking technology, we are expanding opportunities for payments, e-commerce, and financial markets to foster economic growth and inclusivity on a global scale.
Joining our team means being part of a company dedicated to transparency and stability. As we grow, we are extending our operations into some of the world's most robust jurisdictions. Our employees uphold our core values of Multistakeholder, Mindfulness, Driven by Excellence, and High Integrity. Working remotely, our team members thrive in a collaborative environment that encourages fresh perspectives and fosters a sense of ownership.
We are seeking a skilled and experienced smart contract engineer to join our USDC Smart Contract team at Circle. As a Senior/Staff Software Engineer, you will take the technical lead in designing and expanding smart contracts for USDC across various blockchain protocols such as Ethereum, Solana, and Cosmos.
Your responsibilities will include:
- Designing, coding, testing, and deploying secure smart contracts for smooth transactions.
- Improving existing smart contracts to enhance developer productivity, safety, and efficiency.
- Implementing top-tier security practices and performance optimization techniques.
- Conducting risk assessments to identify and address vulnerabilities in smart contracts on diverse blockchain platforms for improved security and robustness.
For a Senior Software Engineer (III), the ideal candidate should have:
- A minimum of 4 years of software development experience (including internships).
- 2+ years of proven expertise in smart contract development on blockchain platforms.
- Proficiency in programming languages suitable for non-EVM smart contracts (e.g., Rust, Go).
- In-depth knowledge of one major non-EVM blockchain ecosystem like Solana or Cosmos.
- Strong focus on architecture, coding, testing, and deploying secure and efficient smart contracts.
- Familiarity with the latest trends in blockchain development to drive innovation.
Requirements specific to a Staff Software Engineer (IV) include all those of a Senior Software Engineer, plus:
- Over 7 years of professional software development experience (including internships).
- 4+ years of hands-on experience in smart contract development on blockchain platforms.
- Expertise in non-EVM programming languages and tech stacks.
- Profound understanding of blockchain technology and various protocols.
- Strong leadership skills to guide technical teams and collaborate effectively.
Both positions are eligible for day-one PERM sponsorship for qualified candidates, and compensation is based on factors like experience and qualifications. Additionally, Circle is committed to fostering an inclusive work environment and offers a competitive compensation package that includes equity, medical, dental, vision, 401(k), vacation policy, sick leave, and multiple paid holidays. Industry Security Practices Best Practices C++ Cybersecurity LOC Token Rewards Multistakeholder eCommerce Policies Pricing.value Merchant Support Engineering Coding Accessibility Safe Checkout Buyer Support.EntityFrameworkCore integrations Seller Facing Revenue.png}.{MongoDB}How to Apply Join us as we create a more transparent and accessible financial future. Apply now to be part of a diverse and inclusive team that values innovation, collaboration, and integrity at its core.
senior solidity developer
It's an on-chain, parametric-first insurance solution designed to deliver fast, fair, and fully transparent coverage.
Our initial offerings include Flight Delay, Smart Contract Risk, and Commercial Property insurance, with plans to expand as oracle infrastructure develops.
Founding Technical Partners for Oferli – Elite Web & Mobile Development Team🌐
The Vision:
Oferli is a 100% decentralized ecosystem. While we are rooted in Web3, our expertise spans across professional web and mobile application development. We are not just another agency; we are crafting the next generation of digital solutions. Our goal is to set a new standard for excellence, transparency, and decentralization.
What I am looking for:
I am building a professional, senior-level "Elite Team." I am looking for partners who are truly passionate about the vision—not just short-term gains. By combining our individual expertise and portfolios, we will establish Oferli’s collective professional reputation.
Requirements:
Proven Expertise: You must be a senior-level professional. Please provide your portfolio showcasing your best work in web and mobile development.
Commitment: This is a founding partnership. We are looking for those who believe in the mission and are ready to tackle complex challenges together.
Professionalism: We operate with high standards. Communication and efficiency are key.
How We Work:
Collaboration: We use professional, secure channels for all communications. Qualified candidates will be contacted via email to be invited to our private workspace on Notion to align on our roadmap and launch our upcoming projects.
Decentralized Operations: We leverage Web3 tools for collaboration and compensation, maintaining a fully decentralized environment.
Growth: We are launching with a core team of at least 5 founding partners, scaling to 10, to deliver high-impact results for our clients.
Application Process:
If you are a senior professional ready to build a world-class, decentralized ecosystem, apply here on LaborX. Qualified candidates will be contacted via email for further professional vetting and onboarding.
Let’s build the future, together.
Sadr B
CEO, Oferli
Senior Blockchain Engineer (Cosmos SDK & IBC)
Expectations:
Design custom modules (x/staking, x/rewards, x/merkl)
Implement IBC light clients and relayers
Optimize block time and state pruning
Write comprehensive unit & integration tests (Go test)
Build CLI tools for validators and delegators
Monitor node health and network upgrades
Collaborate with the research team on MEV-resistant ordering
Maintain chain upgrades (v1 → v2) with migration scripts
Write technical documentation for external validators
Nice to have:
Experience with Avalanche Subnets or Polkadot Substrate
Knowledge of HSM and key management
Open-source contributions to Cosmos SDK or related repos
Chinese+English language proficiency
Senior Mobile application developer
But specially, candidate should be native in English.
Team communication is very important.
Please bid US only
Thank you
Senior Blockchain Engineer - Low-Latency Execution Infrastructure (HyperEVM / Hyperliquid)
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.