SORAMITSU is the developer of and major contributor to the open-source blockchain platform Hyperledger Iroha, which is tailored for enterprise and public-sector use. Hyperledger Iroha, a project of Hyperledger Foundation, part of the Linux Foundation, has a permissions system that is scalable and performant.

Utilizing blockchain, SORAMITSU has developed a digital currency for the National Bank of Cambodia, a CBDC Proof-of-Concept with the Bank of the Lao PDR, a closed-loop payment system for the University of Aizu in Japan, an identity verification system prototype for Bank Central Asia in Indonesia, we were finalists in the Monetary Authority of Singapore CBDC Challenge, and are currently participating in Asia-Pacific's first proof-of-concept test of a cross-border, multi-currency security settlement system using distributed ledger technology with the Asian Development Bank. We have also conducted proof-of-concept tests for several major Japanese enterprises, and are active contributors to open source projects, such as Klaytn, South Korea's leading Layer-1 blockchain, KAGOME, the C++ Polkadot Host implementation, the SORA crypto-economic system, the Polkaswap DEX, and the DeFi wallet, Fearless Wallet

Based on these experiences, SORAMITSU aims to deploy cutting-edge technology on a global level in order to expedite financial inclusion and health, mitigate economic inefficiencies, and contribute to the fulfilment of the Sustainable Development Goals.

You can find out more by visiting our homepage at soramitsu.co.jp or check out our Twitter profile.

We are seeking a highly skilled blockchain developer with deep expertise in blockchain technologies and smart contract development, focusing on Solidity, Ethereum, and various Layer 1 and Layer 2 protocols. This role will involve designing, implementing, and optimizing secure and scalable blockchain solutions.

You will be responsible for:

• Develop, deploy, and maintain secure, efficient, and scalable smart contracts on Ethereum and other blockchain networks.
• Architect decentralized systems and define smart contract standards for new projects and features.
• Lead code reviews and provide mentorship to junior and mid-level developers.Optimize smart contract code for gas efficiency, performance, and security.
• Collaborate with cross-functional teams including frontend developers, product managers, and security experts.Identify and mitigate security risks within smart contracts.
• Stay up-to-date with the latest trends, tools, and best practices in Solidity and blockchain development.
• Perform rigorous testing and auditing of contracts, and ensure all code is secure and bug-free.

Requirements:

• 3+ years working specifically with Solidity and Ethereum-based development.
• Deep understanding of Ethereum's architecture, smart contracts, and related technologies.
• Proficient in Solidity, Web3.js, and Ethers.js.Experience with deploying and interacting with smart contracts on Ethereum, Binance Smart Chain, or other EVM-compatible blockchains.
• Familiarity with common design patterns (e.g., ERC-20, ERC-721, ERC-1155) and decentralized protocols.Expertise in smart contract security practices, including common vulnerabilities (e.g., reentrancy, overflow/underflow, front-running).
• Knowledge of decentralized finance (DeFi) protocols and their smart contract ecosystems.
• Experience with testing frameworks (e.g., Truffle, Hardhat, Foundry).
• Experience with CI/CD pipelines and blockchain-specific deployment strategies.
• Ability to communicate complex technical concepts effectively to both technical and non-technical stakeholders.
• Strong problem-solving, debugging, and optimization skills.
  Preferred:
• Experience in developing for Layer 2 networks or alternative blockchain protocols (e.g., Optimism, Arbitrum, Polygon).
• Familiarity with cross-chain technologies and bridging protocols.
• Experience with smart contract auditing tools like Slither, MythX, and others
• Experience with Polkadot ecosystem (Rust, Substrate)

General Skills:

• Programming Languages: Solidity, JavaScript, Python, with knowledge of Rust considered a plus.
• Blockchain Platforms: Ethereum, Binance Smart Chain, Polygon, Arbitrum, Optimism, etc.
• Frameworks & Libraries: Truffle, Hardhat, Foundry, Web3.js, Ethers.js.
• Security Best Practices: Smart contract auditing, vulnerability mitigation, best practices for gas optimization.
• Collaboration Tools: Git, GitHub/GitLab, JIRA, Slack, etc.
• Soft Skills: Strong communication in English, problem-solving, and analytical thinking.

Additional Requirements:

• Please include a link to your GitHub profile showcasing examples of your code or repositories where you’ve contributed.

What we offer:

• A relaxed remote-first (work from anywhere) work environment with flexible working hours
• A permanent, full-time role with a rapidly growing international team of professionals
• An educational budget to support your continued growth and development
• Opportunities to attend global meetups and conferences for learning and/or speaking engagements
• An opportunity to be a part of an award-winning team designing a better world through decentralized technologies

This is a remote position. Our distributed team is mostly spread across Europe and Asia. Team meetings are held generally during European working hours, and it is expected that you would adapt if necessary and be available accordingly.

If you have the required qualifications and are passionate about the Web3 industry, we encourage you to apply for this exciting opportunity.

SORAMITSU values diversity and is committed to providing equal opportunities for all applicants and employees. Our employment decisions, such as hiring, promotion, discipline, and termination, are based solely on an individual's qualifications, performance, and business needs. We do not discriminate against anyone on the basis of their race, color, religion, marital status, age, national origin, ancestry, physical or mental disability, medical condition, pregnancy, genetic information, gender, sexual orientation, gender identity or expression, veteran status, or any other protected status under federal, state, or local law.

Apply Now:

ip.world is a platform for launching memecoins remixed from popular IPs. We’re reimagining how communities can speculate on the virality of their favorite creative works in a way that allows IP owners and their remixers to collaborate and earn rewards. Our goal is to bridge crypto and mainstream consumer culture by building the ultimate memecoin playground for tokenized IP remixing.

Role

We are looking for a founding smart contract engineer to build out the blockchain infrastructure for our IP remixing memecoin platform. You will lead efforts in designing the core token creation and incentives mechanics, as well as designing liquidity migration strategies and trading integrations with various DeFi protocols. The ideal candidate has a strong background in smart contract programming and EVM (particularly within DeFi), is obsessive over web3 security best practices, and is deeply interested in the memecoin ecosystem.

Responsibilities

• Design an EVM-based token launchpad system using bonding curves for fair-launch distribution and voting-escrow inspired token locking for rewards incentives
• Work with our backend engineer to build an event sourcing pipeline using on-chain indexing solutions such as Subgraph or Goldsky
• Work with our infra engineer to build out on-chain testing environments
• Perform various contract optimizations using Huff or Yul if needed
• Ensure contract security by establishing a comprehensive set of unit / fuzz / integration tests using Foundry along with audits using tools like Slither or Echidna
• Work with external auditors to ensure production readiness prior to launch, designing strategies around module upgrades where appropriate
• Assist with miscellaneous data tasks such as curating Dune Analytics visualizations

Requirements

• 3+ years of industry experience working as a smart contract engineer, esp. in DeFi
• Highly skilled in foundry (preferred) or Hardhat
• Comprehensive understanding of the EVM and MEV
• Deep proficiency in Solidity and basic familiarity with Yul or Huff
• Strong understanding of the mechanics behind the top DeFi and SocialFi projects, including Uniswap v2 / v3, Balancer, Seaport, FriendTech, and Lens
• Strong familiarity of the following types of EIPs: 1167 (minimal proxies), 1014 (create2), 172 (typed hashes), 4337 (AA), 4626 (tokenized vaults), etc.
• Knowledge of DeFi contract auditing and testing best practices
• Experience working with building event-indexing pipelines using on-chain indexing tools like Goldsky or Subgraph, along with familiarity working with tools like Dune or Alchemy
• Past experience in running a self or cloud-hosted blockchain node

What are we all about?

We are a team of builders and researchers on a mission to empower enterprises and developers worldwide to access and build on decentralized systems.

Our expertise covers several domains: Ethereum and Starknet protocol engineering, layer-2, AI, cryptography research, protocol research, decentralized finance (DeFi), security auditing, formal verification, real-time monitoring, smart contract development, and dapps and enterprise engineering.

Working to solve some of the most challenging problems in the blockchain space, we frequently collaborate with renowned companies, such as Ethereum Foundation, Starknet Foundation, Gnosis Chain, Flashbots, Forta Protocol, Lido, EigenLayer, Open Zeppelin, RISCZero, Aleph Zero, and many more.

Today, we are a 350+ strong team working remotely across 66+ countries.

The role

We’re seeking an experienced Smart Contract Security Auditor to join our team in safeguarding Web3 protocols and applications. As a key member of our security team, you’ll conduct comprehensive audits of smart contracts while contributing to our blockchain infrastructure development.

Responsibilities:

• Work directly with protocols in the Solana, Ethereum, StarkNet, and Polkadot ecosystems to review their code and help secure their protocols.
• Perform thorough security audits of smart contracts written in Solidity
• Develop and maintain security tooling using Golang to enhance our audit capabilities
• Collaborate with teammates to maintain and continually improve our existing blockchain security tools using modern software engineering practices.
• Develop new blockchain security tools.
• Engage in meetings with clients to discuss security and best practice improvements.

Skills:

• Understanding of blockchain technology and the Ethereum network.
• Solid understanding of the Ethereum Virtual Machine.
• Fluency in Solidity smart contract security and Golang audit.
• Detailed understanding of common smart contract vulnerabilities.
• Fluency with common tools and frameworks used for the development and security analysis of smart contracts.
• Strong debugging skills and/or experience in reverse engineering.
• Portfolio of audit report.

Nice to Haves:

• Good written and verbal communication skills.
• Understanding of most common DeFi applications.
• Publicly visible audit reports in your portfolio.

Keep up to date on what we are working on by following us on our social channels:

• Discord
• LinkedIn
• Twitter

What are we all about?

We are a team of builders and researchers on a mission to empower enterprises and developers worldwide to access and build on decentralized systems.

Our expertise covers several domains: Ethereum and Starknet protocol engineering, layer-2, AI, cryptography research, protocol research, decentralized finance (DeFi), security auditing, formal verification, real-time monitoring, smart contract development, and dapps and enterprise engineering.

Working to solve some of the most challenging problems in the blockchain space, we frequently collaborate with renowned companies, such as Ethereum Foundation, Starknet Foundation, Gnosis Chain, Flashbots, Forta Protocol, Lido, EigenLayer, Open Zeppelin, RISCZero, Aleph Zero, and many more.

Today, we are a 350+ strong team working remotely across 66+ countries.

Links: Nethermind - Crypto, AI and Robotics

Projects:

• https://github.com/NethermindEth/yayois-garden
• https://github.com/NethermindEth/TruthTok
• https://github.com/NethermindEth/satoshis-razor
• https://github.com/NethermindEth/teeception
• https://github.com/NethermindEth/fremen
• https://github.com/nethermindeth/hummingboss

What We Need

• An engineering manager who is hyper-focused on delivering concrete results while staying excited by the big picture.
• Experienced in leading software teams that ship fast, experiment often, and hand off to product at the right time.
• Hands-on coder but knows when to pull back.
• Views programming languages as easily learnable tools, not identities.
• Driven to optimize everything with AI, leveraging both traditional software and cutting-edge techniques.
• Understanding blockchain or decentralized systems and LLMs is a plus. Personal projects in these areas are required.
• Fully open attitude: embrace the public domain. Production must be robust, but everything else (ideas, prototypes, experiments) should be publicly accessible.

Role & Responsibilities

• Hire and guide leads for multiple AI x Crypto x Blockchain projects.
• Oversee rapid PoC delivery, ensuring minimal friction and maximum velocity.
• Collaborate closely with product managers for timely, high-quality releases.
• Contribute code where it counts.
• Align with an open ethos—innovate in public, build out loud, and keep the end-user ecosystem thriving.
• Comfortably terminate and iterate on projects.
• Liaise with the group manager to set up new AI x Crypto and Robotics projects.

Requirements

• Evidence of having led multiple small to large teams
• Experience shipping open-source code with considerable adoption
• You must be replacing all your interfaces with LLMs

Nice to have

• Experience shipping projects from genesis
• Robotics is not required (we have a hardware team), but some understanding of this space is good
• If these projects are for you, you will feel it. It will be fun, but it will be hard when the air bubble explodes. We will keep building.

Keep up to date on what we are working on by following us on our social channels:

• Discord
• LinkedIn
• Twitter