Learn · Development dos and don'ts
Optimizing code before you know it's actually slow wastes effort and adds complexity for no real gain. You often optimize the wrong thing, since the real bottleneck is rarely where you'd guess. The rule of thumb: make it work, make it right, then make it fast, and only where measurement shows you need to.
Complex "optimized" code is harder to read, change, and debug, so paying that cost without a proven need is a net loss. Most parts of most programs aren't performance-sensitive, and clarity there is worth far more than micro-speed.
The disciplined move is to write clear code first, then measure to find genuine hotspots, then optimize those specifically. That focuses effort where it matters and keeps the rest of the codebase simple.
Updated July 2026
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Because simple code is easier to understand, change, test, and fix, which is where most of a project's cost actually lives. Clever, complicated solutions feel impressive but slow everyone down later, including the person who wrote them. The best code is often the most boring and obvious.
Technical debt is the future cost of shortcuts taken today. When you build something quick and messy to ship fast, you borrow time now and pay it back later as slower changes and more bugs. Like financial debt, a little can be smart, but too much left unpaid eventually cripples progress.
Because code gets shared, copied, and stored in version control, so a password or API key written into it can leak to anyone with access, including the public if the code ever goes online. Leaked keys get abused within minutes by automated bots. Secrets belong in environment variables or a secrets manager, never in the code itself.
The essentials: serve everything over HTTPS, keep software and dependencies updated, use strong authentication and hashed passwords, validate all user input, protect against common attacks, keep secrets out of code, and take regular backups. Most breaches exploit basic gaps, not exotic techniques.
Usually, improve what you have (refactor) rather than starting over (rewrite). Rewrites are tempting but risky: they throw away years of fixes and edge cases, take longer than expected, and often recreate the same problems. Reserve a full rewrite for when the foundation genuinely can't support what you need.
Backups protect you from data loss, whether from a mistake, a failure, a hack, or ransomware. Without them, a single bad event can wipe out your site, database, and customer data permanently. How often depends on how much data you can afford to lose: daily is a common minimum, more for busy systems.