Software Engineer · cover letter
[Date]
Dear [Hiring Manager],
I am applying for the Software Engineer role at [Company]. Last year I rebuilt the checkout service at my current company, cutting p95 API latency from 840ms to 210ms and supporting a Black Friday peak of 12,000 requests per second with zero downtime. That work taught me how much careful design and good instrumentation matter once real traffic arrives.
Most of my time is spent in a Python and Go backend behind a React front end, with PostgreSQL and Redis underneath. I write tested, reviewable code, and I treat on-call seriously. When a memory leak was paging the team every few nights, I traced it to an unbounded cache, shipped a fix, and added the alerting that should have caught it. The pages stopped.
What draws me to [Company] is that you are solving scaling problems I find interesting, and you ship to real users rather than building in a vacuum. I like working close to production, owning a feature from design doc through rollout, and leaving the codebase cleaner than I found it.
What the dashboards caught after that latency drop is worth more than the latency number itself, since they are what let us catch the next regression before Black Friday traffic found it. The repository and the specific commits are there if you want to see the order I made the changes in.
Sincerely,
[Your Name]
[Phone] | [Email]