Battery complaints arrive as one-star reviews saying “drains my battery” with nothing reproducible. How to measure actual drain with Battery Historian and Instruments, and the four causes that account for most of it.
Diagnosing What Your App Does When Nobody Is Looking Read Post »
A teardown of every stage between a click and the first pixel: DNS, TCP, TLS, the HTML preload scanner, render-blocking CSS, parser-blocking scripts, layout, paint, compositing — and which stage your slow page is actually stuck in.
What Actually Happens Between the Click and the Paint Read Post »
EXPLAIN ANALYZE output looks like a wall of numbers. Only four of them matter, it reads inside out, and the gap between estimated and actual rows finds most bad plans on its own.
Security header guides list a dozen headers as equally important. They are not. Nine ranked by the attacks they actually prevent, including three that are obsolete and safe to delete.
Nine Security Headers, Ranked by How Much They Actually Help Read Post »
A service slows down, every client retries, and the retries become the load that finishes it off. How retry storms form, why jitter matters more than backoff, and why retry budgets beat per-request limits.
The model is not hallucinating — it is answering faithfully from bad context. Diagnose retrieval failures in order: is the passage in the index at all, does it rank, and is the embedding model actually the problem?
Why Is My RAG Pipeline Returning Irrelevant Chunks? Read Post »
Pending, ImagePullBackOff, CrashLoopBackOff, CreateContainerConfigError, OOMKilled. Each status points at a different subsystem. A systematic walk through the ones you will actually hit, and the command that resolves each.
Annotating every service method with @Transactional is cargo cult. It holds database connections longer than needed, hides the boundary that actually matters, and silently does nothing when called from inside the same class.
Stop Putting @Transactional on Every Service Method Read Post »
Android WorkManager guarantees deferred work will eventually run; iOS BGTaskScheduler only says it might. Learn constraints, exponential backoff, idempotent workers, the iOS budget model, and how to design sync that survives both.
Deferred Background Work: WorkManager and BGTaskScheduler Compared Read Post »