Avoiding Duplicate Record Errors in Rails Under Concurrency
Two concurrent requests can both pass an exists? check and race to insert the same row; here is why, and how to write idempotent Rails controllers.
Writing
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Why npm ci Runs prepare Scripts for Git Dependencies
npm ci is not the script-free install it looks like; it still runs prepare scripts for Git-based dependencies, which broke Husky in CI.
Handling Out-of-Order Updates in Async Rails Workflows
When async updates to the same record can finish in any order, the oldest write can silently overwrite the newest one; here is how to stop that.
Poetry vs uv: Choosing a Python Dependency Manager
Poetry and uv solve overlapping problems in Python dependency management; here is where each one wins, and how to use them together.
Deadlocks in MySQL and PostgreSQL: Foreign Keys vs Performance
How deadlocks form in MySQL and PostgreSQL under concurrent updates, and the trade-off between foreign key integrity and write throughput.
Catching Database Configuration Drift Between Microservices
Two services sharing a database can pass every test and still fail in production if their DB configuration silently drifts apart.
React Dev Proxy Options: package.json vs http-proxy-middleware
Two ways to avoid CORS errors in local React development: the package.json proxy field for one backend, or http-proxy-middleware for several.
Detecting Cloudflare Zero Trust Beyond the WARP Flag
WARP can report itself as off while Zero Trust still routes your Mac's traffic; here is how to check DNS, ASN, and DoH to find out for sure.
Monitor Cloudflare WARP Status on macOS with launchd
A launchd-scheduled shell script that detects when Cloudflare WARP reconnects on a company-managed Mac and sends a desktop notification.
Debugging in Ruby, Python, and PHP: byebug, pdb, and Xdebug
Compares Ruby's byebug, Python's pdb, and PHP's Xdebug side by side, with the core commands and a working example for each language.