BlockchainEngineer_FullyRemote

As a Blockchain Engineer at BLOOMTECH, you'll design, develop, and operate blockchain-related systems for a next-generation financial platform. You'll join a Japan-based startup aiming to become a decacorn, backed by a listed company group, and work on a cross-border remittance infrastructure project launched with an international organization. You'll collaborate with product managers and engineers across domains to build globally deployed financial infrastructure using a diverse technology stack, while shaping technical direction, development processes, and design principles for an autonomous team.

What you'll do

• Design, develop, and operate blockchain-related systems
• Design and develop smart contracts
• Research and implement emerging technologies in the blockchain space
• Ensure system scalability, maintainability, and security
• Define requirements, clarify specifications, and align stakeholders on technical direction
• Design highly available APIs and optimize infrastructure using managed cloud services
• Build CI/CD pipelines and maintain comprehensive documentation

What you bring

• Solid software development fundamentals demonstrated through production experience in one of the following: library, framework, or middleware development; high-load systems (social gaming, ad tech); high-reliability systems (data infrastructure, FinTech); or distributed systems (blockchain, IoT)
• Core knowledge of algorithms, data structures, networking, security, and design patterns
• Blockchain product development experience in one of the following: smart contract design and implementation (Solidity, Rust, or similar); blockchain node or infrastructure construction and operations; wallet integration, signature processing, or key management; or involvement with Web3, DeFi, or NFT services
• System design and operations experience with at least one major cloud platform (AWS, GCP, or Azure), including managed services for computing, storage, databases, networking, serverless, containers, or messaging

Nice to have

• Expertise in blockchain and cryptography, Zero-Knowledge Proofs (zk-SNARKs, zk-STARKs), multiparty computation (MPC), or homomorphic encryption
• Experience with token design or smart contract security audits
• Knowledge of L2 and Rollup technologies or distributed consensus algorithms (PoS, BFT, etc.)
• Experience with signature and cryptography techniques or identity management (Passkey, ECDSA, BLS signatures, ECIES, etc.)
• Development with strongly typed languages such as Go, Rust, Kotlin, Java, C#, or C++
• Frontend development with React or Vue
• Backend framework experience with Express, Koa, Spring Boot, Ktor, or similar
• Infrastructure as Code experience with Terraform or CloudFormation
• Financial systems development or operations experience
• Large-scale data design, operations, or analysis
• IoT or device development with Raspberry Pi, Arduino, M5Stack, or similar

What we offer

• Annual salary of 8,000,000 to 18,000,000 JPY
• Fully remote work
• Flexible working hours

About BLOOMTECH

BLOOMTECH is a Japan-based startup aiming to become a decacorn, backed by a listed company group. Since 2018, it has pursued global deep tech infrastructure development. The company is launching a cross-border remittance platform using stablecoins to enable fast, low-cost, and convenient international payments.