Jun 1
When Prompt Engineering Hits a Ceiling
For the last two weeks I've been stuck on the same bug in ResumeMatch.
7 min read
Writing24 posts · Since 2025
Notes on systems, LLMs, and the industry building them.
I'm Wenhao, a software engineer. I write up system design problems I've worked through, what I'm learning about LLMs, notes from shipping side projects like ResumeMatch, and the occasional take on layoffs and where the industry is heading.
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Mar 30
Adding a DynamoDB Caching Layer to a Serverless LLM Pipeline
Another late night on Sunday shipping features. This week I added a caching layer to ResumeMatch that drops duplicate analysis latency from 25 seconds…
8 min read
Mar 21
How I Fixed False Negative Keyword Matching in My LLM-Powered Resume Analyzer
Happy Friday! Weekend's almost here, but before I sign off, I wanted to write up a fix I shipped this week for ResumeMatch.
10 min read
Mar 14
Debugging CORS and Rate Limiting in a Serverless App
Happy Saturday! Or at least it was supposed to be. Two hours ago I cracked open ResumeMatch to check something quick and walked straight into a blank…
6 min read
Feb 9
New Year, New Certification
It’s 2026, and it’s been a while since I last published a blog post. Today feels like a good reason to break that silence.
5 min read