Performance is priceless
Every plugin you add runs PHP, queries the database, and may enqueue scripts or styles. A single poorly-coded plugin can add noticeable latency, harm Core Web Vitals, and reduce conversions for your client.
- Test on staging with real content before deploying.
- Measure impact using tools like GTmetrix, Web Vitals, or Query Monitor.
- Prefer lightweight plugins or server-side solutions when possible.
Security starts with the right code
Plugins are a common attack vector. Choosing reputable, maintained plugins reduces the chance of vulnerabilities that could compromise a client site — and your agency's reputation.
- Check plugin authors, review counts, and changelogs.
- Avoid plugins without recent updates or a support history.
- Run vulnerability scans and subscribe to WP vulnerability feeds for critical clients.
Less is usually more
Each plugin is an additional dependency. Fewer plugins mean fewer compatibility risks, simpler updates, and faster debugging.
- Ask if the feature can be done with core WordPress or simple custom code.
- Prefer multi-purpose, well-maintained plugins over many single-feature ones.
- Document every plugin you install and why it’s required.
Maintenance is part of the deliverable
Selecting a plugin means committing to its lifecycle. Abandoned plugins break with WP updates and create technical debt.
When onboarding a client, include a plugin audit in your SLA and schedule periodic reviews.
Compatibility and conflict checks
Plugin conflicts are common. Establish a simple workflow to spot them early:
- Use a staging environment that mirrors production.
- Enable WP_DEBUG and check logs when activating new plugins.
- Test theme, plugin, and PHP version compatibility.
A practical plugin checklist for agencies
✔️ Active maintenance (updated within last 3–6 months)
✔️ Good support / community presence
✔️ Clear changelog and versioning
✔️ Small performance footprint (load-tested)
✔️ No known security vulnerabilities
✔️ Works with the project's PHP / WP version
✔️ Reasonable pricing & licensing for client use
Final recommendations
Make plugin decisions part of your onboarding checklist. Treat plugins like third-party services: review them, test them, document them, and include maintenance in your contracts. Doing so protects your clients, preserves site performance, and keeps your agency sane.