No Server Space Needed: Test Plugins and Themes with Playground – Interview with Adam Zieliński

🎙️ On this episode of Osom To Know, we dive into the world of WordPress development with our guest, Adam Zieliński. Adam is a WordPress Core Commiter from Auttomattic. We discuss the concept of playground for test environments, where users can run a temporary WordPress in their browser to test plugins or themes, eliminating the need for server space. Adam suggests using playground for product demos, allowing users to interact with plugins or themes on a company’s website without the need for screenshots or videos.

💡 Adam’s passion for solving large systemic problems shines through as he discusses his innovative projects, such as the HTML tag processor and the playground feature. These solutions have the potential to be game changers for the WordPress community, making it easier for new contributors to get started. We wrap up the episode with Adam’s inspiring journey in creating a tutorial for Gutenberg and his prototype that allows WordPress to be run in a browser tab, simplifying the initial setup process.

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Why WordPress Playground Exists: Kill Setup, Start Building

Playground wasn’t a formal assignment. It grew from curiosity and the freedom to experiment.

For teams and clients, that “day‑zero” setup often felt like wasted budget and energy—hours spent fighting installs, extensions, and configs. When Adam Zieliński saw that environment setup routinely derailed, he set out to remove the setup step itself. His goal was simple: make WordPress instantly accessible, with no downloads, no Docker, and no setup.

I started creating WordPress Playground last year to solve a problem with starting with WordPress that was just too hard.

What started as a simple Gutenberg tutorial soon turned into a breakthrough idea. Within a week, Adam had a working prototype. Months later, it became the Playground — a tool that lets developers spin up full WordPress instances directly in their browser, without any server space at all.

Instant Onboarding: Test WordPress Plugins & Themes with No Server

Playground eliminates the hardest step in onboarding: the setup. Instead of losing hours to installation errors or local environment bugs, new developers can start coding instantly — even from a browser tab.

We went from downloading WordPress, setting everything up… to just running a single command.

Adam shared an example from WordCamp Athens, where 70 developers used Playground-based tools during an Interactivity API workshop. The results spoke for themselves: almost zero technical issues and a room full of working setups within minutes. That reliability proved that Playground could do more than simplify tutorials — it could redefine how WordPress contributors learn, test, and teach.

How WordPress Runs in the Browser (WebAssembly Explained)

Playground uses WebAssembly, a technology that lets you run desktop-grade programs right inside your browser. It’s what makes PHP and MySQL run locally without any server.

By compiling WordPress into WebAssembly, Adam and his team unlocked an entirely new way of running the platform. The result: faster load times, no server dependencies, and an unprecedented level of portability for both developers and educators.

Playground’s potential stretches far beyond development environments. It’s becoming a tool for demos, education, and experimentation.

You can put Playground on your homepage if you’re a company working on a plugin or a theme and then allow people to interact with it right there. No screenshots, no videos — you just show your product.

This use case alone transforms how plugin authors and theme creators can showcase their products. Adam also envisions a near future where users can move their Playground-built site straight to hosting. Playground might soon power live previews, pull request tests, and even user-ready website creation—all without touching a remote server.

Next for WordPress Playground: Mobile, and Live Testable Docs

Adam’s long-term vision pushes Playground into the territory of edge computing and mobile-first performance. The project demonstrates how WordPress can live closer to users, running partially or fully in their browsers.

What if the entire WordPress was just downloaded to your device? Maybe you only do it once, and every time you visit a WordPress site, you just download a small database file and browse that.

It’s a futuristic concept, but with WebAssembly now widely supported across browsers and cloud providers, it’s no longer just theoretical. For Adam, it’s about freedom — bringing WordPress everywhere, from mobile to edge networks.

The Playground project keeps expanding as new contributors and ideas flow in from the WordPress community. Adam’s next focus areas include live testable documentation, educational integrations, and blueprints for CI pipelines and mobile apps. Every small advance opens doors to new use cases.

Get Involved: Contribute to WordPress Playground Today

Playground began as an experiment and evolved into a cornerstone for open collaboration in the WordPress ecosystem.

I invite everyone to come over to the repo, join the Playground Slack channel, and help us build it all.

Helping can be anything — sharing a problem, proposing a solution, or contributing code. You don’t need to know any WebAssembly to do that. For Adam Zieliński, this project is proof that when you remove barriers and open the door to experimentation, innovation naturally follows.

Full conversation with Adam about WordPress Playground

Watch the full episode “No Server Space Needed: “Test Plugins and Themes with Playground – Interview with Adam Zieliński” at Osom to know podcast. For more conversations on WordPress innovation and open-source engineering check out our YouTube – don’t forget to hit subscribe! 📩