Want code that runs faster and costs less to maintain? Small changes add up fast, and you can get big wins with focused work.
Start by measuring. Profile before guessing where the slow parts are. Use a profiler that fits your stack — py-spy, perf, Instruments, or a built-in tool. Collect real data, then tackle the hotspots that matter.
Pick better algorithms and data structures. A sort, hash, or tree change often beats micro-optimizations. If your search is O(n) and can be O(log n) with a simple swap, do it.
Cache smartly. Memoize expensive function results, cache database queries, and push static assets to a CDN. But set sensible expiration rules so you don’t serve stale data.
Reduce allocations. In languages like C++, Rust, or Go, avoid needless copies and reuse buffers. In Python or JavaScript, avoid building huge temporary lists when a generator or stream will do.
Parallelize where it helps. Multithreading or async I/O can speed I/O-bound tasks. For CPU-heavy work, use multiple processes or native threads, or move work to a worker service.
Prefer built-ins and libraries. Language-native functions and battle-tested libraries are often faster than homegrown code. NumPy, std::vector, the right SQL index — they save time and headaches.
Write small functions and keep responsibilities clear. Small, tested pieces are easier to optimize. Add benchmarks for hotspots and run them in CI so you spot regressions early.
Code reviews matter. Ask reviewers to check algorithmic choices and risky allocations, not only style. A second pair of eyes often spots a cheap improvement.
Use tracing, profiling, and logging together. Flame graphs show where time goes, heap tools expose leaks, and request traces tie user pain to code. Monitor production with lightweight probes.
Automate simple wins. Add compile optimizations, minify assets, gzip responses, and run database vacuum or analyze tasks on a schedule. These steps cost little and pay back fast.
Measure cost, not ego. If an optimization saves pennies but doubles complexity, skip it. Focus on changes that reduce latency, cut server bills, or improve user experience.
Try one small change today: add a profiler, cache a heavy query, or drop an extra copy. Measure the result, then repeat. Efficient code grows from steady, practical work.
Database work: add indexes on bad queries, avoid N+1 selects by joining or eager loading, batch writes instead of single-row commits, and prefer LIMIT+OFFSET alternatives for deep pagination.
Frontend wins: trim JavaScript, defer nonessential scripts, lazy-load images and embeds, and serve compressed modern formats. Small asset changes often cut page time by seconds.
Language tricks: in Python use join for strings, list comprehensions, and built-in functions. Try PyPy or compile hotspots with Cython. In C/C++, prefer reserve and move semantics to avoid copies.
When you hit hard limits, offload work to specialized services. Use caches like Redis, search engines like Elasticsearch, or GPUs for heavy parallel math. Moving work often reduces cost and complexity.
Measure, change, and keep the performance scorecard updated.