Code Efficiency: small changes that save hours

Want your code to run faster and your workday to be less painful? Code efficiency isn’t just about raw speed — it’s about writing code that’s easier to read, test, and change. Start with small habits that give big wins: pick the right data structures, measure before optimizing, and keep functions focused. Those three moves alone cut bugs and speed up future work.

Measure first. I always run a quick profiler or add timing logs before guessing where the slowdown is. Profilers (cProfile for Python, built-in Chrome DevTools, or perf on Linux) point to the real hotspots. Optimize what matters. Wasting time on code paths that rarely run is a classic trap.

Choose the right algorithm and data structure. A simple switch from a list search to a hash lookup (map/dict) can turn O(n) into O(1) and feel like magic. Sort once when necessary, avoid nested loops when you can use a set, and favor built-in functions — they’re usually faster than hand-written loops.

Keep functions small and focused. Smaller functions are easier to test and reason about. When a function does one thing, you can profile, cache, or replace it without breaking other parts of the app. Name functions clearly so the code reads like a story — future you will thank present you.

Practical patterns that pay off

Cache expensive results when they’re reused. Memoization works great for deterministic functions. Use lazy loading for heavy resources — load data or modules only when needed. Batch operations instead of repeating work in tight loops: one bulk database write beats many small writes every time.

Avoid premature optimization but don’t ignore common sense. Clean code is often fast enough. If you see repeated code, refactor it. Duplicate code means duplicate bugs. Use copy-paste only when you’re sure it won’t need separate fixes later.

Tools and habits that keep code efficient

Use linters and formatters to remove trivial slow patterns and enforce consistency. Run unit tests and quick integration checks in CI so performance regressions get noticed early. Code reviews are gold — another pair of eyes often spots an expensive operation or a simpler alternative.

Adopt a few editor shortcuts and snippets to avoid boilerplate. Time saved typing is time you can use to think through better designs. Learn your framework’s standard libraries — they usually include optimized helpers for common tasks.

If you touch backend or database code, watch queries. Add indexes for frequent filters, avoid SELECT * in hot paths, and prefer prepared statements. For frontend work, reduce DOM updates and avoid heavy repaint loops; use virtualization for long lists.

Finally, build a short performance checklist for each project: measure, profile, pick a clear hotspot, apply the smallest safe change, then test. Repeat when new features arrive. Efficient code comes from steady habits, not last-minute miracles.