Yuki Hayashita

I am a Professional Services Consultant at Amazon Web Services Japan, specializing in cloud solutions. As an AWS-certified professional with expertise in serverless architecture and full-stack development, I focus on designing and implementing innovative cloud solutions that drive business value. With a Computer Science degree from Brown University and a background in software engineering, UI/UX, and systems development, I combine technical expertise with a passion for creating efficient, user-centric solutions.

Weenix

C
Operating Systems

Weenix is a Unix-like operating system that I developed its major parts for in CS1690 at Brown.
Parts that I implemented include:

- Procs: threads, processes, and synchronization primitives
- Drivers: device drivers for terminals, disks, and the memory devices (/dev/zero & /dev/null)
- VFS: common interface between the OS kernel and the file systems
- S5fS: file system based on the original Unix file system built on top of VFS
- VM: virtual memory maps, page fault handler, system calls, anonymous objects, and shadow objects that achieve a fully functional OS that is capable of managing user address spaces, running user-level code, and servicing system calls.

A full documentation written by Brown University is available here.

TCP over IP over UDP

Go
Computer Networking
IP
TCP
UDP

I implemented IP-TCP project which involves implementing a virtual network with a router (vrouter) and host (vhost) using a shared IP stack library. The IP stack includes a virtual link layer and network layer for sending and receiving IP packets. The project focuses on IP-in-UDP encapsulation, IP forwarding, and implementing features such as longest-prefix matching. The TCP project extends this network, building TCP on top of the virtual IP layer. It includes components like sockets, a TCP state machine, and a sliding window protocol. The TCP stack is integrated into the existing host, and a Socket API is created for socket interaction. The implementation follows RFC standards, and capstone students may implement congestion control algorithms. The project involves testing through REPL commands and evaluating performance using Wireshark capture files.

Citi

Java Spring Boot
Angular
C++
SQL
Fullstack

I worked with a project manager and stakeholders at Citi Tokyo to modernize a legacy internal tool written in C++ by designing in Figma & developing an application in Java Spring Boot + Angular + SQL. I managed a large C++ code base, documented complex financial business logic, and transferred them to the new application.

Patronus Deer (TeamLab)

C#
HLSL
GPU Computing
Unity
TouchDesigner

Patronus Deer is a projection mapping art installation that I made as a project for my internship at TeamLab. The artwork was made in Unity by using C# scripting, HLSL (shader language) and GPU computing in HLSL. I realized a wall where you can touch and interact with the deer and particles, resulting in immersive user experiences. Laser rangefinders and Open Sound Control were utilized to capture human inputs from a conventional wall. I employed GPU parallel computing to achieve real-time rendering of 100,000+ curl-noise particles.

Lingualens

Figma
Prototyping
Product Strategy
UI/UX
System Design

Lingualens is a web extension that reveals in-depth language analysis on hover and lets you add to flashcards such as Quizlet or Anki, streamlining the language learning experience. Our team crafted a prototype of the application using Figma and conducted system design for the software. This effort culminated in our recognition with the Best Design Hack award at Hack@Brown 2024.

Hack at Brown 2023 Website

Three.Js
React.js
Figma
Frontend
UI/UX

Hack@Brown 2023 is a hackathon that was hosted at Brown University in 2023. As someone who was on both the design team and dev team, I worked with designers to create our website design in Figma and then worked with engineers to develop the frontend. The theme of the website was Campfire, and all components were 3D models made in blender. I managed all the 3D models and made them all come to life in our website using Three.js and react-three-fiber.

Sourcing Brothers Website

Three.js
HTML
CSS
Frontend
Adobe XD

I worked with designers to develop 3D interactive background graphics for the website for SOURCING BROTHERS Co. ltd. Graphics are coded in Three.js using physics concepts and are made responsive to different screen sizes.

Shinjuku Partners Website

p5.js
HTML
CSS
Frontend
Adobe XD

I worked with designers to develop interactive background graphics for the website for Shinjuku Partners Accounting Firm. Graphics are coded in p5.js using physics concepts and are made responsive to different screen sizes.

Scape

Javascript
Hackathon

Scape is a particle simulation game which I developed for Hack@Brown 2022. Coded in pure Javascript, the game lets you play with sand, plant seeds, water the plants to grow them, and strike a lightning the burn everything! I was awarded First-time Best Hackathon for this submission.

Xmas Scene

C++
GLSL
Computer Graphics

Xmas Scene is a final project that I worked on in a team for CS1230 at Brown University. We individually coded an entire graphics software from scratch in Qt in class and added more functionalities as a team to create this xmas scene. The additional functionalities were Parallax Mapping, Shadow Mapping, and Particle Effects. The software was coded in C++ and GLSL, using the Phong Illumination Model.

Hyperboloid

Processing
Java

Hyperboloid is an artwork made in Processing. It uses a simple mathematical concept to form a hyperboloid in the 3D world. Written in Java.

Aurora Fluid

Processing
Java

Aurora Fluid is an artwork made in Processing. It uses the concept of gravity and Perlin Noise to create an interesting blob and its movement. Written in Java.

Trigonometry Dance

Processing
Java

Trigonometry Dance is an artwork made in Processing. It uses a simple mathematical concept of trigonometry to form a sphere in the 2D world. Written in Java.

Lorenz Dragonz

Processing
Java

Lorenz Dragonz is an artwork made in Processing. It uses the mathematical concept of Lorenz System to form a dragon-like shape in the 2D world. Written in Java.

Processing – Particle River

Processing – Recursion Christmas Tree‍