July, 2023 - Current: Tech Lead at a crypto hedge fund
Designed and developed a high performance and secure trading system using Rust, Solidity and GCP/GKE.
Developed CI/CD infrastructure to improve development agility using GitHub Actions and ArgoCD.
Developed Observability infrastructure using Datadog.
Project management of a small team and code reviews. Responsible for improving the productivity of the developers and ensuring the quality and speed of the team’s output.
Researched on MEV/Flashbots and incorporated them into actual strategies. Also doing research on relatively new DeFi protocols such as interest rates and perpetuals.
April, 2023 - November, 2023: Software engineer at Phi
Created Quests using Ethers.js/Typescript. Worked on a feature to mint the user’s on-chain history as an identity with integrating to smart contracts of other prtocols (DeFi protocols such as Timeswap and sudoswap and other famous projects such as Mirror and Lens).
Added some features to a new smart contract (PHIMaterial), communicated with an audit team and addressed security issues in response to the audit reports. (The work was done in a separate private repository, but it is not in the history because it was committed together as an initial commit in this repository for public use.)
Formulated new feature specifications, designed architecture, and developed using Typescript and AWS.
Designed and developed wallet authentication system.
Analyzed the effectiveness of the measures by Dune and created a dashboard.
October, 2020 - September, 2022: Software engineer at Mercari
Worked at Platform group
Develop infrastructure and provide middleware and internal system across organization such as Mercari, Merpay, Mercoin
Developed temporary privilege granting system to promote Zero Touch Production. The objective was to reduce failure and security risks by avoiding direct human contact with the production environment, including SREs. Developed Kubernetes custom controller with Go and user interface with React.
Designed and developed cost visualization platform to optimize infrastructure resources and monetary costs.
Introduced policy audit system to enhance security of our Kubernetes infrastructure.
Others
AbemaTV
Belonged to Ad Association of AbemaTV and participated in launch of a new big feature
Developed a few microservices in Go on Kubernetes
Improved observability, planned load test and built load environment for more production ready microservice.
Observability: introduced distributed tracing(OpenCensus/StackdriverTrace), profiling(pprof) and build monitoring system(Prometheus, Grafana).
Load test: made scenarios, prepared the production equivalent data, and got loads on the system with Locust
Performance tuning: tuned the performance of the application, Envoy parameter and pod replica size based on the load test
Developed a helper application with TypeScript, Cloud Function, Cloud Pub/Sub, Terraform, etc
BASE
Participated in launch of a new fintech business
Developed the API in Go (adopt TDD and Layered Architecture)
Introduce golangci-lint
Developed the frontend application in Vue.js collaborating with an designer
An application kernel, written in Go, that implements a substantial portion of the Linux system surface. Used in container services in GCP such as Cloud Run and GKE.