Debugging AWS Lambda OOM: Why In-Memory File Decryption Blew Up Our Python Runtime

How a file decryption and spreadsheet parsing pipeline in Python 3.12 triggered sudden Out-Of-Memory (OOM) crashes in AWS Lambda, and how leveraging ephemeral /tmp storage fixed our production pipeline.

October 4, 2026 · 5 min · 993 words · Samba Namuduri