JUN KIMURA

I’m a hacker and entrepreneur. I specialize in abstracting complex problems and building frameworks and middleware to solve them. My expertise spans from developing cutting-edge technologies to applying them in real-world products that address practical challenges.

Professional Experience

Datachain (2018–Present): Co-founder, CTO, Research Engineer

  • Leading research and development in blockchain interoperability, with a particular focus on IBC, light client algorithms, and middleware enabling cost-effective on-chain light client verification
  • Supporting the development of TOKI, a cross-chain token transfer protocol, by providing core infrastructure and technical design based on IBC and LCP
  • Designing and developing PoCs in collaboration with partner companies (e.g., Progmat, MUTB, Toyota Financial Services, NTT DATA, etc.)
  • See the “Media” section for notable project coverage

Representative projects include:

  • LCP: A proxy middleware that enables light client verification using Trusted Execution Environments (TEE)
  • zkDCAP: A zero-knowledge proof-based Intel SGX DCAP quote verification system
  • Hyperledger YUI: An implementation of the IBC (Inter-Blockchain Communication) protocol for Ethereum and other enterprise blockchains
  • Cross Framework: A framework for building smart contracts that support cross-chain transactions via IBC
  • Hypermint: A Tendermint-based blockchain supporting WASM smart contracts
  • Ethereum L2 Plasma chain: Developed using Solidity, Golang, and Tendermint

Freelance: Lead Engineer

Worked on backend systems in the adtech industry, primarily focused on building and scaling infrastructure to handle high-traffic environments.

  • High-performance ad server (>100,000 RPS): Built with Golang, Aerospike, AWS, Jenkins, Ansible, etc.
  • Large-scale ad log batch processing: Implemented with Golang, Fluentd, and go-flow

Momentum (2014–2017): Co-founder, CTO

Developed and launched an ad verification service to protect advertisers from brand risk. Successfully integrated the service with DSPs and ad networks.

  • Ad verification platform (brand safety, ad fraud detection): Go, JavaScript, Python, AWS, GCP (BigQuery)
  • Designed a batch system capable of crawling tens of millions of URLs per hour
  • Built a content classification system in collaboration with a laboratory at Tokyo Institute of Technology
  • Acquired by a KDDI Group company

JustSystems (2013): Software Engineer

  • Built backend systems for an ecommerce: Java, Scala, Play Framework, PostgreSQL, Redis, AWS
  • Conducted research and development on similar-image retrieval systems as an experimental project: Python, OpenCV, Apache Solr

Open Source (As Founder)

The following are projects I initiated. For additional contributions, please visit my GitHub: https://github.com/bluele

Technical Skills

  • Programming Languages: Rust, Go, C, Python, JavaScript
  • Confidential Computing: Intel SGX
  • Databases: MySQL, Redis, Aerospike
  • Blockchain: Ethereum, Tendermint, Cosmos-SDK, IBC
  • Cloud Platforms: AWS, Azure, GCP

Media Coverage