Undo Git mistakes - reflog after reset --hard, soft reset, revert pushed commits, restore, recover deleted branches

JavaScript numbers lose precision - 0.1+0.2, MAX_SAFE_INTEGER, JSON.parse rounding big IDs, BigInt, toFixed and money handling

Jq cookbook for API JSON - select, map, group_by, null-safe access with //, CSV output, --arg for shell variables, JSON Lines and common errors

Debug a failing GitHub Actions workflow - triggers, YAML and expressions, permissions, secrets, cache and runner differences

Design idempotency keys - unique key table, request fingerprint, in-progress 409, replay stored response, TTL, concurrent-duplicate tests

Fix stale content behind a CDN - read Age and cache-status headers, Cache-Control per file type, hashed filenames, targeted purge, Vary traps

Fix JavaScript async bugs - missing await, forEach with async, serial vs parallel awaits, Promise.all vs allSettled, unhandled rejections

JavaScript gotchas run live - default sort as text, map(parseInt), == coercion, Date parsing UTC vs local, NaN includes, var closures

JavaScript Promise patterns - all vs allSettled vs race vs any results, forEach async trap, timeout wrapper limits, concurrency pool of 3

JavaScript regex cookbook - matchAll named groups, /g lastIndex statefulness, replaceAll TypeError, lookbehind, u flag emoji and unicode classes, ReDoS

Fix LLM context window overflow in long agent runs - token budgets, protected state and safe summarization

Diagnose high load on a Linux server - CPU, memory and swap, disk iowait, pressure stall info and the runaway process

Debug Kubernetes ingress 404 and 503 errors - ingress class and rules, Service selectors and ports, empty endpoints, probes and backend protocol

Build a small LLM evaluation dataset - real cases, edge and refusal tests, code and model graders, holdout split and per-change score tracking

Cut LLM API cost with prompt caching - stable-prefix prompt layout, cache-hit measurement, context trimming, model routing and batch jobs

Add authentication to a remote MCP server - API keys vs OAuth 2.1, audience and scope checks, per-tool authorization, Origin checks and audit logs

Diagnose Kubernetes CrashLoopBackOff and OOMKilled pods - exit codes, previous logs, probes and limits

Troubleshoot Kafka consumer lag and rebalances - partition parallelism, max.poll.interval.ms, heartbeats, poison messages, offset commits and skew

Make your site and API discoverable to AI agents - llms.txt, OpenAPI and MCP manifests, intent-first descriptions, sitemap and registry listings

Linux disk full - df -h vs df -i inodes, du -x sorted, deleted files held open by a process (lsof +L1), truncating logs, ext4 reserved blocks