
Software Engineer — New York
Kelan
Liu
Scaling backend systems, grounded in AI/ML.
About
Product-drivensoftwareengineerattheintersectionofbackendsystemsandAI.CurrentlybuildingatClassLink.PreviouslyatWaymo.
MS Computer Science, ML & AI — UT Austin
BS Computer Science — Lehigh University
Outside of work — personal finance, Olympic weightlifting, and motorcycles.
Experience
ClassLink
Jan 2024 – PresentSoftware Engineer
- ·Architected and implemented a serverless translation management system supporting localization across multiple product front ends; delivered a department-wide presentation on problem context, architecture, and system design (Python, TypeScript, AWS Lambda, S3)
- ·Collaborated cross-functionally across teams to ship features end-to-end, contributing directly to adjacent team codebases
- ·Developed backend APIs and event-driven automation workflows using Node.js, TypeScript, and Python, deployed on Amazon ECS and AWS Lambda
- ·Optimized critical SQL queries, reducing database query costs by up to 68% (MySQL, Redis)
- ·Built a resilient request library with retry logic and exponential backoff, reducing socket hangups and server-side errors
- ·Identified and patched a privilege-escalation vulnerability caused by misconfigured AWS SES IAM permissions
- ·Built a multi-agent AI debugging tool using Claude Code with a log-tailing watcher agent, interactive code-fix session, and automated QA agent for curl-based validation (Python, Bash)
Waymo
Sept 2021 – Jan 2022Software Engineer, Machine Learning, Research Intern
- ·Contributed to a real-time autonomous driving simulation platform through kinematics modeling and cloud visualization integration (C++, Python)
- ·Partnered with Simulation and UI teams to refine scenario realism and optimize user interaction workflows, improving fidelity across kinematics modeling, visualization, and driving UI
- ·Built an operator-facing driving UI and a data collection pipeline for simulation workflows (Angular, RxJS, TypeScript, Protobuf)
- ·Optimized end-to-end latency to under 200ms by implementing D3.js-based visualization tools for monitoring rendering and mapping plugin performance
- ·Significantly improved intern permission pitfalls by implementing intern-friendly scripts for existing software infrastructure
Intuidex
May 2021 – Aug 2021Software Engineer Intern
- ·Ported and optimized video-processing and ML algorithms for embedded GPU systems using CUDA, Docker, and Python
- ·Implemented and optimized real-time motion detection algorithms supporting a YOLO-based license plate detection pipeline for the Jetson Nano and Xavier (OpenCV)
- ·Reduced object detection and classification training runtime by 4 minutes on a large training dataset of thousands of vehicles
Projects
GramIt
GitHub →Online multiplayer game combining social interaction and creative image selection. Built with AWS Step Functions for real-time game state management and XState for frontend state machines.
Instant Object Tracking
GitHub →Web app and API for real-time video analysis with bounding boxes, classifications, and class probabilities. Uses YOLOv5 and SORT for object tracking with multithreaded parallel processing.
Tiny-GPT
GitHub →A Transformer decoder stack with self-attention trained on raw text data. Built from scratch with a 16x32 tensor (batch size x block size) and a 9:1 training to validation set split.
Tech Stack
Languages
Cloud & Infra
Frameworks
AI / ML
Get in touch
Let's build
something together.
Kelan.