Top Software Engineer Jobs in Yokohama

Build full-stack tools, backend services, APIs, dashboards, and data workflows for assessing and improving AI training data and evaluations. Partner with quality and research teams to inspect agent trajectories, validate graders, measure quality, investigate workflow issues, and turn internal prototypes into reliable production platform capabilities.

Develop and maintain scalable Python applications, APIs, microservices, and data pipelines using PySpark and Airflow. Deploy and operate solutions on Azure with Docker and Kubernetes, implementing monitoring, logging, alerting, and production support. Collaborate with product managers, data scientists, and engineering teams on global projects while contributing to coding standards, architecture, testing, documentation, and Agile delivery.

Lead backend design and development for a mobile-first strategy-building fintech: build scalable Python/FastAPI services, real-time APIs/WebSockets, integrate market data providers, optimize performance across large datasets and simulations, contribute front-end React/TypeScript work, maintain containerized deployments and CI/CD pipelines, and document and collaborate in an async-first team.

Participate in full-stack development and maintenance of Binance’s KYC system, including backend services, frontend features, documentation, testing, regression, troubleshooting, and customer issue resolution. The role is a 3–6 month accelerator internship for current university students and recent graduates, with an emphasis on Java, Spring Boot, databases, middleware, and frontend technologies.

Design and build interfaces for HUD’s AI agent training, evaluation, and marketplace products. Translate complex reinforcement learning workflows, agent runs, evaluation results, reward signals, and quality feedback into clear, actionable experiences. Collaborate with users, researchers, and engineers to ship polished products, conduct user discovery, improve usability, and develop reusable interaction patterns.

Participate in developing and maintaining Binance’s KYB backend system. Document business-module interfaces, support functional and regression testing, track bugs with QA, troubleshoot reported issues, and help customer-support teams resolve and classify problems. The role requires Java, Spring microservices, MySQL, NoSQL, middleware, strong communication, and teamwork. It is part of a 3–6 month accelerator internship for current students and recent graduates.

Develop realistic backend coding challenges, including feature implementations and bug fixes, for AI training projects. Design deterministic verifiers, automated tests, and validation criteria that distinguish correct from incorrect solutions. Evaluate code for correctness, reliability, maintainability, security, and performance while identifying edge cases and bottlenecks. Work independently with backend technologies and refine tasks based on project requirements and quality standards.

Build and operate production custody systems: signing service, key management, chain integrations, and transaction pipelines. Own end-to-end subsystems, integrate new chains, collaborate with cryptography on threshold signing and key recovery, write post-mortems, and produce clear async design docs and PRs.

Develop and maintain full-stack applications using React.js, Node.js, Java, AWS, MySQL, and DynamoDB. Build responsive frontend components, secure RESTful APIs, cloud-native services, and CI/CD deployments. Participate in Agile ceremonies, code reviews, troubleshooting, documentation, testing, and collaboration with product, design, QA, and DevOps teams. Use AI-assisted development tools for coding, testing, debugging, refactoring, and documentation.

Participate in developing and maintaining core products, implementing business-module interface documentation, troubleshooting QA-reported issues, and supporting customer-service teams with problem resolution and system improvements. The role requires Java and Spring microservices knowledge, database and middleware experience, strong communication skills, and collaboration in a global blockchain environment.

Participate in developing and maintaining core products, compiling business-module interface documentation, troubleshooting issues identified by QA, and assisting customer support with problem resolution and system improvements. The role requires Java and Spring microservices knowledge, database and middleware familiarity, strong communication, teamwork, and logical problem-solving skills.

Designs and develops blockchain security products, core frameworks, APIs, infrastructure, and automation for large-scale distributed systems. Responsibilities include architecture standards, performance tuning, incident troubleshooting, system refactoring, continuous delivery, capacity management, and reusable libraries. The role also engages users, coordinates with cross-functional teams, and addresses security risks involving blockchain, smart contracts, wallets, and on-chain attacks.

Build core components of a diagnostic and personalization platform: backend data pipelines, frontends, services for genomic data ingestion, ML model integration, APIs, and cloud infrastructure. Collaborate with product and ML teams, iterate on prototypes and MVPs, and make architectural decisions supporting scalability and reliability.

Participate in developing and maintaining core products, compiling business-module interface documentation, troubleshooting issues identified by QA, and helping Customer Support resolve and categorize customer problems. The role is part of a 3–6 month early-career accelerator internship focused on blockchain and digital assets. Candidates should have strong Java, Spring microservices, database, middleware, communication, teamwork, and problem-solving skills.

Participate in developing and maintaining core products, documenting business interfaces, troubleshooting issues identified by QA, and supporting customer-service teams with problem resolution and system improvements. The role requires Java development, Spring microservices, database and middleware knowledge, strong communication, teamwork, and learning ability. Experience with Web3 projects is preferred.

Design, build, and optimize scalable LINE messaging services, LIFF applications, and LINE MINI Apps on AWS. Develop product features and internal tools, integrate with an advertising platform, translate business needs into technical solutions, and improve ecosystem performance. The role requires collaboration across Japan and the United States, strong software engineering fundamentals, and business-level Japanese and English communication.

Build and scale Base360.ai’s short-term rental platform, including customer-facing applications, APIs, automation engines, AI-powered workflows, third-party integrations, and cloud infrastructure. Develop systems for reservations, pricing, payments, guest communication, property operations, reporting, and financial workflows. Own projects end to end, make architectural decisions, ensure reliability, and deliver scalable products in a remote-first startup environment.

Develop, optimize, and deploy AI applications on customer silicon; provide technical training and support; reproduce and resolve pre- and post-silicon software issues; build benchmarks and proofs-of-concept; collaborate with R&D for fixes and performance tuning; create documentation and customer-facing collateral.

Design, build, and maintain scalable, high-availability brokerage systems for Japan. Develop backend microservices, APIs, financial integrations, and middle- and back-office systems supporting multi-currency transactions, accounting, settlement, and Japan-specific regulations. Collaborate with global engineering teams and Japanese regulators, vendors, and partners; translate requirements into technical solutions. Participate in incident response, on-call rotations, architecture, mentoring, recruitment initiatives, and regional engineering projects.

Own HUD’s production infrastructure and backend platform systems, focusing on reliability, scalability, performance, cost, deployment safety, and developer experience. Build AWS infrastructure with Terraform and Kubernetes, improve CI/CD and observability, design resilient services and asynchronous systems, manage incidents, and develop internal automation and tooling. The role supports high-availability AI, marketplace, and data-heavy workloads.

Lead backend architecture and build scalable, high-concurrency services and APIs (Node.js) powering web and mobile. Own components end-to-end, manage CI/CD and infrastructure (IaC, containers, cloud), improve reliability, and collaborate with PM/design to deliver core features like live interactions and checkout.

Build and operate scalable data pipelines for autonomous-driving machine learning workflows. Responsibilities include ingesting, transforming, curating, validating, and monitoring large real-world and synthetic datasets; improving pipeline performance and reliability; supporting scenario mining and model evaluation; and collaborating with ML engineers, Data Corpus teams, AI Platform, and external partners.

Build full-stack product surfaces, backend services, APIs, databases, dashboards, internal tools, vendor workflows, and observability for reinforcement learning data and evaluation systems. Develop interfaces for browsing environments, inspecting trajectories, reviewing quality, debugging failures, and understanding model behavior. Partner with research, operations, vendors, and go-to-market teams to translate ambiguous requirements into reliable products. The role also involves production debugging and cloud infrastructure collaboration.

Design and implement open source networking solutions, collaborate with cloud providers, and contribute to technical documentation and community efforts.

As a C# Software Engineer, you'll design and implement classes for document IDE, refactor code for extensibility, and interview users to understand needs.