Daily micro-tips for C#, SQL, performance, and scalable backend engineering.
Same code, different results. WhyLocal time zones and daylight saving. Fix DateTimeOffset.UtcNow 🔥 Why DateTime.Now Breaks Distributed Logic (And What to Use Instead) Same code. Different results.If you’ve ever seen time-based logic randomly fail in production, DateTime.Now might be the silent culprit. In distributed systems, local time is a trap. 🚨 The Core Problem […]
Readable code, hidden cost. WhyMultiple enumerations. Fix var list = items.ToList();
Looks async, behaves sync. WhyCPU-bound work inside async methods. Fix await Task.Run(Compute);
Works fine in testing. WhyDifferent execution order under concurrency. FixStandardize access order across queries.
Indexes exist, scans happen. WhyImplicit type conversions. Fix WHERE UserId = @UserId — matching types
Logs enabled, throughput drops. WhySynchronous logging blocks request threads. FixUse async logging providers.
GC runs, memory stays high. WhyObject pooling misused or ignored. Fix services.AddPooledDbContextFactory<AppDbContext>();
No conflicts shown. WhyRebase rewrites local commits. FixStash or commit before pulling with rebase.
Commits exist, meaning is lost. WhyGeneric commit messages destroy context. FixEnforce semantic commit conventions.
Fast internet hides the bug. WhyRace conditions between requests. FixCancel in-flight requests before sending new ones.
One click triggers multiple handlers. WhyListeners added repeatedly without removal. Fix element.removeEventListener(‘click’, handler);
Desktop works, mobile doesn’t. WhyAutoplay restrictions require muted playback. Fix <video autoplay muted playsinline></video>
Looks fine on desktop, broken on mobile. WhyImplicit grid tracks expand unexpectedly. Fix grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
No error, no recovery. WhyGPU Timeout Detection triggers silently. FixUpdate GPU drivers and adjust TDR settings.
Wi-Fi connects, speed collapses. WhyPower-saving resets network drivers. FixDisable power management for network adapters.
Prompt Explain this topic at three levels: 1. Beginner 2. Practitioner 3. Expert Include real-world examples. Topic: <INSERT TOPIC>
Prompt Refactor this code. Constraints: – Preserve behavior – Reduce cognitive complexity – Improve naming and structure Explain WHY each change helps. Code: <PASTE CODE>
Prompt Act as a concurrency expert. Analyze this code for: – Race conditions – Thread safety violations – Unsafe shared state Explain the exact execution paths. Code: <PASTE CODE>
Same image, different result. WhyCI runs on a different CPU architecture. FixBuild multi-arch images explicitly.
Metrics look fine, pods stay the same. WhyCPU-based autoscaling ignores I/O-bound workloads. FixScale using custom or request-based metrics.
Works for some users, fails for others. WhyAuthentication cookies blocked by SameSite rules. FixAdjust cookie settings for cross-origin REST calls.
The page renders quickly… after waiting. WhyHeavy server-side hooks delay the first byte. FixProfile PHP execution time, not frontend assets.
Layers exist but edits lag. WhyNested smart objects create deep render chains. FixFlatten completed sections and keep only active smart objects.
Design looks perfect, performance tanks. WhyHidden metadata and color profiles inflate file size. FixStrip metadata on export and convert to sRGB explicitly.
You rename a method… and production breaks. Why this happensReflection, DI containers, and source generators bypass static reference tracking. Why it mattersRefactors appear safe but silently break runtime behavior. FixSearch for string-based registrations and generated code outputs before refactoring.
Works until scale. WhyExceptions are expensive. Fix if (!TryParse(…)) return;
Even in managed code. WhyUnsubscribed event handlers. FixAlways unsubscribe or use weak events.
Surprising but true. WhyLarge structs copied by value. Fix void Process(in MyStruct data)
Random slow queries. WhyExecution plans cached incorrectly. Fix OPTION (RECOMPILE)
Same query, worse performance. WhyMissing covering indexes. Fix CREATE INDEX IX_User_Email ON Users (Email) INCLUDE (Name, CreatedAt);