April 18, 2026
Vibe code vs. database reality
A story about how I dug into the PostgreSQL sources to write my own WAL receiver
He built a Postgres log catcher; fans cheer, pros say use WAL‑G and don’t vibe code
TLDR: A developer built a custom tool to capture Postgres change logs after reading the source. Comments praised the learning but pushed mature tools like WAL‑G, warning this isn’t a place for “vibe coding” because nasty edge cases can break real backups—great story, serious stakes.
A developer fell down the Postgres rabbit hole and ended up building his own “log catcher” — a tool that grabs a database’s stream of changes for backups. The crowd loved the journey. One camp cheered the grit and the author’s newfound respect for C after spelunking through source code; you can feel the learning in every line. They called it a love letter to old‑school engineering and a peek behind the curtain of a famously careful database. For many, it felt like watching a DIY thriller for databases.
But the knives and links came out fast. The top nudge: why reinvent when WAL-G already does this in Go? That lit up the classic showdown: curiosity builds vs production tools. Pragmatists warned this is exactly what you “never ever want to vibe code” — backups and replicas fail in sneaky ways, and edge cases will eat you. Humor kept pace: “arguing with fsync” (a file‑saving step) became a meme, and folks joked he now greets “.partial” files like old friends. Others name‑dropped pgBackRest and Barman as the “grown‑ups.” Final vibe from the thread: inspiring story and great write‑up — but for real data, bring armor or bring a proven tool.
Key Points
- •The author investigated pg_receivewal’s internals by building PostgreSQL from source and studying receivelog.c.
- •This exploration led to writing a custom WAL receiver and comparing it step by step with the original utility.
- •Key complexities identified include connection drop handling, restarts, .partial-to-complete file transitions, timeline switching, and fsync placement.
- •The author assessed established tools: pgBackRest (comprehensive, robust) and Barman (simple orchestrator using pg_receivewal and pg_basebackup).
- •The custom tool is being implemented in Go, with the author noting a growing respect for C through the process.