How to choose a WordPress plugin developer: a procurement checklist

When your business relies on a custom WordPress plugin—whether for a membership system, a booking engine, or a data integration—choosing the right developer is a procurement decision with long-term consequences. A poorly built plugin can slow your site, introduce security holes, and lock you into costly maintenance loops. This checklist helps you evaluate developers beyond their portfolio gloss.

1. Verify technical competence beyond WordPress

A developer who only knows WordPress hooks and filters may struggle with complex logic, database performance, or API integrations. Ask about their experience with:

• PHP version compatibility – Does the plugin run cleanly on PHP 8.x? Many older plugins break.
• Database query optimization – Will the plugin handle thousands of records without slowing your admin panel?
• Third-party API integration – How do they handle rate limits, error handling, and data sync?
• JavaScript and modern front-end frameworks – For admin interfaces that need to be responsive.

Ask for a code sample of a previous plugin (not a site they built) and review the structure, comments, and error handling.

2. Evaluate security practices upfront

A malicious or sloppy plugin is a common vector for WordPress site compromises. During the procurement process, ask:

• Do they sanitise and validate all user inputs? This includes form data, URL parameters, and file uploads.
• Do they use nonces and capability checks? Without these, any logged-in user could trigger admin actions.
• Are they GDPR-compliant? If the plugin stores user data, they should explain encryption, data retention, and deletion.
• Do they follow WordPress coding standards? The WordPress.org plugin review team has published guidelines—good developers follow them even for private plugins.

Request a brief security audit report or ask how they handle vulnerability disclosures. If they dodge, that’s a red flag.

3. Assess long-term maintainability

Most business plugins need updates: WordPress core changes, PHP evolves, and your requirements shift. A procurement checklist must include maintenance terms:

• Documentation – Do they provide inline code comments and a user-facing manual?
• Version control – Will you have access to a private Git repository?
• Update policy – How long do they guarantee compatibility with WordPress updates? What’s the cost for post-launch fixes?
• Handover plan – If you switch developers, can they export the plugin code and database schema cleanly?

A developer who treats the plugin as a “one-time build” is likely to leave you stranded after a major WordPress release.

4. Test communication and project management

During the procurement process, observe how the developer communicates. Do they ask clarifying questions about your business logic? Do they push back on unrealistic timelines professionally? Do they provide a clear scope of work with milestones and deliverables? A developer who is vague during sales will be vague during development.

We recommend a paid discovery phase (2–3 hours) where the developer writes a mini-spec and estimates effort. This filters out casual freelancers who don’t understand your business needs.

5. Understand the plugin’s performance impact

A bloated plugin can degrade your site speed and hurt user experience. Ask for:

• Load time benchmarks – How many database queries does the plugin add per page load?
• Caching compatibility – Does it work with common caching plugins like WP Rocket or W3 Total Cache?
• Scalability testing – Have they stress-tested the plugin with simulated high traffic?

If they can’t provide numbers, consider it a risk. Performance issues are expensive to fix after launch.

6. Review contract and ownership terms

Finally, the legal side. Your procurement checklist should confirm:

• Full code ownership – You own the plugin, including all source code, assets, and documentation.
• Non-compete clause – The developer should not sell the same plugin to your direct competitor without customisation.
• Warranty period – Typically 30–90 days for bug fixes after launch.
• Exit clause – What happens if the developer disappears? Do they provide escrow or a fallback?

Many business owners skip this step and regret it when a developer goes freelance or gets acquired.

When custom makes sense—and when it doesn’t

Not every WordPress problem needs a custom plugin. Off-the-shelf solutions are cheaper and have community support. However, if your workflow is unique, your data is sensitive, or you need deep integration with proprietary systems, a well-vetted developer is worth the investment. Use this checklist to separate the pros from the amateurs.

If your team is evaluating a custom plugin project and wants a partner who follows these standards, we can help. At AUMCREATE, we build secure, maintainable WordPress plugins for businesses that need more than a template.