★Blockchain Engineer | Featured Fin-tech Company

• Business Level Japanese Required

◆ Famous Venture Company

◆ Flextime & Fully Remote Work

◆ Own Products/Services

◆ Great Welfare

◆ Annual salary: 8 million yen -15 million yen

【About the company】

The company creates value through technology by implementing blockchain in society.

In order to promote the social implementation of blockchain, the company conducts PoC with partner companies, business planning, and R&D in the areas of scalability and interoperability, which are challenges for blockchain.

Blockchain technology is still in its infancy, but over the past few years, various demonstration experiments and R&D projects have been conducted around the world, and the groundwork has gradually been laid for social implementation in terms of both business and technology.

The company has also accumulated knowledge and expertise in the use of blockchain through joint projects with leading Japanese partner companies in the financial and mobility fields.

【Examples of Initiatives】

The company and Toyota Financial Service conduct a demonstration experiment for "proof of value" and "transfer of ownership" of vehicles using blockchain.

In the area of R&D, the company is developing solutions for scalability and interoperability, which are frequently pointed out as blockchain issues.

The company is sincerely committed to "social implementation of blockchain" and realizing the creation of value through technology.

【 Job Description】

■Mission for This Position

You will work with the team to handle the design, development, and operation of blockchain-related systems for a new business that will support the next generation of financial systems. They expect you to leverage diverse technical stacks and collaborate with Product Managers and engineers from other domains to drive the construction of a globally deployed financial infrastructure.

You will be involved in building a development framework that balances speed and quality, which includes everything from designing highly available APIs and optimizing infrastructure using managed cloud services to building CI/CD pipelines and preparing documentation. In this role, you will help formulate the foundational technical policies, development flow, and design principles, joining a team that drives development autonomously. You will also work to gain consensus with stakeholders on ambiguous requirements and new domains, translating those technical concepts into concrete implementations.

【Responsibilities】

• Designing, developing, and operating blockchain-related systems.

• Designing and developing smart contracts.

• Researching and implementing new technical domains.

• Ensuring system scalability, maintainability, and security.

• Defining requirements and specifications, and building consensus with stakeholders.

etc.

■Position Highlights

• You can join as a core member from the launch phase of a new business.

• You will be involved in building the next-generation financial infrastructure on a global scale.

• You will have the opportunity to proactively contribute to the team's technology selection and development framework.

• You will be exposed to cutting-edge technologies like blockchain.

■ Technologies Used

• Frontend - TypeScript, Vite, Biome, ESLint, Vitest, Storybook, MSW, Sentry, etc.

• Backend - TypeScript, Jest, etc. (technology selection in progress)

• Blockchain - Go, Solidity, Hyperledger Besu, etc.

• Infrastructure - Various AWS services (CDK, Lambda, Aurora, Kinesis, etc.)

■Recruitment Background

In the next-generation financial system, the backend and blockchain domains are critical components that support the product, playing an essential role in system scalability, maintainability, security, and integration with other domains. These areas demand long-term, stable development while continuously deepening expertise. In this position, the company expects you to support their in-house development framework by taking a mid-to-long-term perspective as an engineer, focusing on technology selection and the improvement of development processes.

■The Company's Challenge

Since its founding in 2018, the company has focused on R&D for technology and business opportunities with the goal of creating a "de facto standard infrastructure" as a "Japan-born, global deep tech" company.

It is anticipated that virtually all assets—particularly those backed by real-world value, known as "Real World Assets (RWA)" (e.g., stocks, bonds, derivatives, real estate)—will become digital assets. With the financial system on the verge of a major transformation, the company is leveraging its accumulated technical expertise to build the next generation of global financial systems. For this reason, the company is heavily focused on recruiting personnel, primarily for its product development teams.

■About the Team

You will join a cross-functional team and contribute to product development using modern methodologies, collaborating with both domestic and international members from diverse backgrounds in an international work environment.

【 Requirements】

■Required

• Development experience requiring foundational implementation skills (any of the following):

Development experience with libraries, frameworks, middleware, etc.

Development in technically challenging environments: high load (social games, ad tech), high reliability (data infrastructure, FinTech), or distributed systems (Blockchain, IoT)

• Fundamental knowledge of software development: algorithms, data structures, networking, security, design patterns

• Product development experience using blockchain technology (any of the following):

Design and implementation of smart contracts (e.g., Solidity, Rust)

Construction and operation of blockchain nodes and related infrastructure

Implementation of wallet integration, signature processing, key management, etc.

Development of blockchain-powered services (Web3/DeFi/NFT, etc.)

• Experience designing and operating systems using major cloud services (AWS / GCP / Azure)

Experience utilizing managed services such as computing, storage, databases, networking, serverless, containers, and messaging

• Japanese: Business level~

• English: Understand system-related English literature and apply it to implementation

■Preferred Requirements

Any of the following:

• Blockchain and cryptography

• Zero-Knowledge Proofs (zk-SNARKs, zk-STARKs, etc.)

• Multi-party computation (MPC), homomorphic encryption

• Token design, smart contract security audits

• Layer 2 / Rollup technologies, distributed consensus algorithms (PoS, BFT, etc.)

• Signature/cryptography/identity management (Passkey / ECDSA / BLS signatures / ECIES, etc.)

• Programming languages

• Development experience using strongly typed languages such as Go / Rust / Kotlin / Java / C# / C++

• Frameworks

• Frontend (React / Vue, etc.)

• Backend (Express / Koa / Spring Boot / Ktor, etc.) development experience

• Infrastructure / IaC

• Experience designing and building cloud environments using IaC tools (Terraform / CloudFormation, etc.)

• System development and operations experience in the financial sector

• Design, operation, and analysis of large-scale data (Data Scientist domain)

• Development experience with IoT/devices (Raspberry Pi / Arduino / M5Stack, etc.)

■Ideal Applicants

• Business-Driven Technical Judgment: You can flexibly select and make optimal technical decisions by understanding business objectives, even when requirements and the business environment are changing.

• Team Collaboration and Contribution: You don't just focus on your own development; you proactively support the team and promote mutual growth through information sharing and technical discussions.

• Knowledge Sharing and Improvement Mindset: You contribute to the overall ease of development and technical skill improvement of the team through design, code review, and thorough documentation.

• Proactive Problem Solving: You willingly identify challenges and proactively propose and implement improvements in all areas necessary for the product's success, not just technical system domains.

【Working Time 】

Flextime System

【 Welfare 】

・Full Social Insurance

・Commuting Allowance

・Stock Option

Making an environment where engineers can be more enthusiastic and excited about development together with the engineers.

・High-spec MacBookPro is provided every two years.

・A keyboard and mouse of your choice are provided.

・Choice of chairs (Ergohuman or Contessa)

・Side jobs are allowed (personal service development, technical advisor, etc.)

・Book purchase expenses covered (up to 10,000 yen per month)

・Company pays for up to 10,000 yen per month for personal use of cloud environment

・Library for employees (O'Reilly's latest publications are delivered as needed)

・Lounge work environment with sofas and standing tables

・Unlimited coffee (using Speee's original blend of beans)

・Conference participation expenses covered (lodging and travel expenses also covered)

・Assistance in obtaining qualifications (the company will pay up to 30,000 yen for any qualifications related to your work)

【 Holiday 】

• Saturday/Sunday/National Holiday
• Annual Paid Leave
• New Year Holiday
• Summer Holiday, etc