Behavioral Question

Key	Value
Vision	I believe reliability is the most important part of any product. My mission is to dramatically grow amazing products in a startup environment by balancing agility and reliability. I am also interested in LLMs and want to explore how they can create the next generation of development experiences.
Career Goal	My career goal is to move to the US, join the OSS community deeply, and lead developing wonderful technologies and products in startup markets.
Introduction	I am a Software Engineer with 7 years of experience specializing in reliability engineering. I have developed enterprise-grade distributed systems in startup environments, effectively balancing reliability and agility. I am skilled in Golang and Java development and Kubernetes cluster management. As side projects, I contribute to OSS like Kubernetes, Etcd, Raft, and a workflow engine. I also study Computer Science online at CU Boulder while working in Japan.
Past Job	I studied Engineering at the University of Tokyo. I worked with patient data, developed Python models, and wrote a paper. As a first role, I joined Gunosy, Japan's largest news app with 40 million users. I worked as a data engineer for 1.5 years and improved advertisement performance using big data. As a second role, I co-founded Industry Technology for real estate companies. As CTO, I led the development team and wrote entire backend code in 5.5 years. As a third role, I joined Cybereason as a Software Engineer, helping to operate a distributed cybersecurity platform that processes 80 million events per second across 12,000 servers worldwide. In parallel with these roles, I have contributed to several AI/LLM-focused startups as side projects, designing and improving backend systems.
Why searching a new position	I am satisfied with my current job and am not actively seeking. However, I have clear vision and career goals. I am always open to new opportunities that can help me grow and succeed. I am waiting for the right opportunity to move to the US and receive help with visa support.
Why applied	This role fits my vision and career goals perfectly. My experience matches what you need. I learned backend developments and leadership at Industry Technology. I learned SRE practices and teamwork at Cybereason.
Why CU Boulder	I wanted to study computer science basics again, especially AI. CU Boulder has flexible online classes with modern AI courses.
Why Cybereason	I joined Cybereason for the reliability challenge - their system handles 80 million events per second on 12,000 servers.
Why left CTO	We sold the business. After that, I chose to be an IC instead of a business leader.
Why SRE	I successfully introduced SRE practices at Industry Technology and got an enterprise contract. I learned that SRE practices are very important skills for all software engineers.
Why Backend	The responsibility fits my vision and career goals completely.
Why Freelance	The projects matched my vision and career goals. I worked on OSS, AI/LLM, and high-reliability systems.
Why US	The US has big OSS and startup communities. I can work on large-scale, high-reliability systems to drive the development of amazing products.
Career Path	I prefer the IC path. My ideal role is a Senior Backend Engineer who uses SRE practices. I understand soft skills matter for leaders. I enjoyed teamwork at Cybereason. I enjoyed leadership at Industry Technology.
Visa	I can work through PEO/EOR arrangements. I am prepared to relocate and will cover my own visa expenses.
Interesting	I really enjoy developing observability features like custom metrics and distributed tracing. (CR1) At Cybereason, I built custom metrics that improved observability for 3,000 servers.
Strength / Positive Feedback	My strength is my background in both SRE and backend development. On infrastructure teams, I'm the fastest programmer, and on backend teams, I'm the strongest system designer. (IT1) At Industry Technology, I designed SLIs/SLOs and developed custom metrics and tracing to make the system more reliable.
Weakness / Negative Feedback	Weakness: I sometimes focus too much on quality instead of agility. Summary (New):At Industry Technology, I spent too much time on code reviews, which delayed PR merges. Situation: My reviews took too much time and slowed down the team because I focused heavily on quality and detail. Action: To solve this, I improved our CI pipelines and added AI review tools to help. Result: As a result, PRs were merged faster while maintaining high quality. Learning: I learned that thorough automation helps increase speed while maintaining quality.
Failure	Summary (New): I introduced an E2E test automation tool at Industry Technology, which accidentally created silos between teams. Situation: I added an automation tool to help frontend engineers save time on writing tests. But it created walls between frontend and QA teams and hurt teamwork. Action: We stopped using the tool. I gave E2E testing to frontend engineers so they owned their code quality. Result: As a result, teams worked better together and product quality improved. Learning: I learned that tool choices must think about team impact, not just technical benefits.
Leadership / Business Impact / Difficult Decision / Innovative Idea	Summary (IT1): I introduced SRE practices at Industry Technology, which helped win an enterprise contract. Situation: Japan's largest real estate company wanted our system, but our operations were not good enough for them. Task: My mission was to improve reliability to meet their needs and get their trust. Action: I paused new feature developments and implemented SRE practices. I created SLIs/SLOs and built metrics and distributed tracing. I also prepared monitorings and on-call schedules. Result: As a result, we won the enterprise contract. Learning: I learned that there are times even in a startup environment when reliability must be prioritized.
Ownership	Summary (EN1): I developed a generator tool at enechain, which helped 50 developers deploy faster. Situation: All developers manually wrote terraform and kubernetes configs for each microservice, which was slow and error-prone. Task: My mission was to automate this to save time. Action: I developed a generator tool even though it wasn't my main mission. Result: As a result, new microservices were deployed much faster for all teams. Learning: I learned that taking ownership beyond my main tasks helps accelerate the entire company.
Teamwork	Summary (CR2): I led cross-functional teams as an incident commander at Cybereason, which fixed a critical issue affecting an enterprise company. Situation: An API server kept crashing for a big customer. We needed many teams (SRE, DevOps, Product, TAM) to work together. Task: My mission was to find the problem and fix the system urgently. Action: As an incident commander, I organized all teams. We checked thread dumps and heap dumps to find the cause and implemented a fix. Result: As a result, we solved the ticket and got the customer's trust. Learning: I learned that fixing incidents needs both tech skills and good team coordination.
Technically Challenging	Summary (EU2): I developed a real-time logging system for a workflow engine at Eukarya, which delivered millisecond-level status updates. Situation: Users needed to monitor workflow status right away after execution, but we had no good logging mechanism. Task: My mission was to build real-time logging system with cost efficient architecture. Action: I used Pub/Sub design with Redis cache and GCS for storage. Result: As a result, users saw worker status in real-time. Learning: I learned that I can balance performance and cost to build an efficient system.
Conflict	Summary (New): I disagreed with an engineering manager about migrating 3,000 servers, which led to a better migration strategy after discussions. Situation: Management and engineering managers wanted to migrate some servers from Google Cloud to Oracle Cloud within 6 months to save infrastructure costs. Task: My mission was to share my technical concerns while supporting business goals. Action: First, I disagreed and presented specific data: I showed that multi-cloud complexity would increase ops burden by 50% I explained that our team had no Oracle Cloud expertise I calculated that API differences would require 3 months of code changes After that, I proposed a compromise solution: We should start with non-critical services as a pilot We could hire Oracle support engineers as consultants We would migrate core services only after pilot success with proper planning After discussions with an engineering manager, we agreed on a phased migration plan with Oracle consultants to guide us. Finally, once the decision was made, I fully committed to the plan and helped the migration. Result: As a result, we migrated successfully and saved significant infrastructure costs. Learning: I learned that effective conflict resolution requires "disagree and commit" - voice concerns with data, but once a decision is made, fully support it and work toward success.
Low Performer	Summary (New): I mentored a struggling engineer at Industry Technology, which helped him become a lead backend engineer. Situation: A frontend engineer joined the backend team but struggled. He wanted to transition to a backend engineering career. Task: My mission was to help him grow without slowing our work. Action: I did regular 1-on-1s and made learning docs for him. Result: As a result, he became a lead backend engineer. Our docs also helped train all new engineers. Learning: I learned that helping people grow benefits everyone afterwards.
Refactor / Rearchitecture / Legacy	Summary (IT4): I migrated from monolith to microservices at Industry Technology, which improved system scalability. Situation: Our monolith system had database problems when traffic grew. Task: My mission was to split it into microservices to reduce load. Action: I migrated to microservices with no downtime utilizing BFF layer. Result: As a result, the system became simpler and database performance improved a lot. Learning: I learned that migrating a system with no downtime requires several times more effort than a typical one.
Quick Learn	Summary (EU1): I quickly learned WebAssembly at Eukarya, which enabled users to extend the workflow engine. Situation: Users wanted to use their own scripts (Python, Go, Rust) to extend the workflow engine. Task: My mission was to add WebAssembly support for user custom scripts. Action: I learned WebAssembly quickly, developed the feature, and wrote docs for the team. Result: As a result, users got an intended feature and the team learned WASM. Learning: I learned that individual learning can become a valuable asset for the team.
Tight Schedule	Summary (IT2): I delivered group chat system at Industry Technology on a tight schedule, which increased user engagement. Situation: We had a tight deadline for a group chat and notification system. Task: My mission was to design and develop the system on time. Action: I used polling instead of WebSockets - inefficient but simpler design. Result: As a result, we shipped the feature on time and user engagement went up. Learning: I learned that good-enough on time beats perfect but late.
Missed Deadline	Summary (CR3): I fixed an API bug at Cybereason after core engineers left, which prevented losing trust from an enterprise customer. Situation: We had a bug in a core API. But the original developers left with little documentation. Task: My mission was to fix this bug in one sprint. Action: When I realized it would be delayed, I sent regular progress reports to the customer and TAM. Result: As a result, we finished a week late but with good documentation and testing. The customer liked our honest updates. Learning: I learned that it's important to share regular updates with stakeholders to manage their expectations.
My Question	Agility vs Reliability: How does your team balance speed and reliability? Diversity: I am Asian. Does your team value diversity? Career Path: If I do well, what career paths exist? Can you help with visa support and relocation? Expectation: What do you expect from the ideal candidate? Legacy: What problems does your legacy system have? Business Impact: How important is this team to the company? LLM: I've worked with LLMs. How does your team use them? Interview Process: What are the remaining steps? What should I prepare? Learning: Does the team learn new technologies? Number: What's the scale of your system? Decision: What important decision did your team make recently? Background: How big is the team? What are their backgrounds? Project: What is your team working on now? Restriction: What things slow down daily development productivity? Favorite: What is your favorite thing and least favorite thing? Company Value: Ownership: Can I help other teams improve? Think Big: Can I make bold decisions? Conflicts: Did you experience any conflicts within your team?