Drupal is well known for its flexibility, and with good reason. But unlocking that flexibility takes more than installing a few modules or toggling settings in the admin panel. It takes planning, structure, and a solid understanding of Drupal’s theming system.
Your theme isn’t just the visual layer of your site. It’s a critical part of your platform’s performance, scalability, and editorial workflow. A good theme serves your users, but also your team, your brand, and your roadmap.
Let’s explore what it takes to build a Drupal theme from scratch. Not the code (you can find that elsewhere), but the process, the decisions, and the philosophy that make a custom theme worth the investment, whether you’re learning how to create a custom theme in Drupal 10 step by step or planning your first Drupal 10 rollout.
Too many teams underestimate the importance of theming in the early stages of a project. They assume it’s something you can bolt on once the backend is ready. But the reality is that themes define how everything comes together — from content layout to frontend performance to user accessibility.
“Think of the theme as the connective tissue between your content and your users,” says Yauhen Bayeu. “It’s not just how the site looks. It’s how it breathes.”
A well-built custom theme can improve loading speed, enhance SEO, support accessibility compliance, and drastically improve the experience for editors managing content.
“One of the first things I ask clients is, who’s using the site, and who’s updating it? The answers to both shape how we build the theme,” he adds.
Whether you’re building a lean marketing site or a dynamic publishing platform, your theme is part of the architecture, not a layer on top.
Using existing base themes
Base themes like Stable or Bootstrap can save time, especially for smaller sites. But they come with assumptions — about design systems, markup structure, and dependencies — that may not align with your goals. Over time, they often require heavy customization.
Generating themes with visual tools
Theme generators, like TemplateToaster, offer a visual alternative. You don’t need to write code, you just drag, drop, and export. That’s convenient for non-technical teams, but the tradeoff is maintainability. The generated themes can be rigid or poorly structured.
Building a theme from scratch
The third and most robust option — and the one we recommend for production-grade projects — is building a custom theme from scratch. That means setting up a lean, efficient structure that does exactly what your team needs and nothing it doesn’t.
If you’ve ever tried to create Drupal theme setups using generic tools, you’ve likely hit limitations. That’s why many teams turn to custom Drupal themes.
“It’s like tailoring a suit,” Yauhen says. “Off-the-rack themes might fit okay. But if you want precision, speed, and flexibility, you build one that’s made for your shape.”
No theme should begin with markup. It should begin with understanding.
Theming is not a creative flourish at the end of a project — it’s a translation layer between business objectives and user experience. That’s why the first step in any theming process should be sitting down with stakeholders to define clear goals.
What kind of content will the site host?
Is it static or dynamic?
Do certain templates repeat frequently?
What’s the ideal balance between automation and editorial control?
These aren’t just nice-to-ask questions. They directly shape the architecture of the theme. A campaign-heavy site might prioritize flexible layouts and content-driven components, while a publishing site might need strict structure and a clear editorial hierarchy.
“Design follows purpose,” Yauhen points out. “You can’t build a great frontend until you understand the backend — not the code, but the purpose. A theme that works for an internal portal might be useless for an ecommerce site. The goals shape everything.”
Teams also need to identify how content will evolve over time. Is the site a fixed presentation layer for services, or will it grow with frequent updates, seasonal campaigns, or language versions? The more dynamic the environment, the more carefully the theme needs to support content scaling without breaking consistency.
These early conversations aren’t just about structure — they help avoid major rework later. If you know your content team needs the ability to mix and match components on a page, that influences the approach to layout regions and template logic. If accessibility is non-negotiable, your markup needs to reflect that from the first line of code, not as an afterthought.
Yauhen emphasizes that technical constraints should never define the editorial workflow.
“We try to avoid the trap where the CMS dictates how people tell stories. The theme should support communication, not limit it.”
When building a custom Drupal theme — whether for Drupal 8, 9, or 10 — we don’t think in pages. We think in patterns. That means identifying reusable components — from cards and banners to navigation menus and article teasers — and organizing them in a way that scales.
“You’re not designing a homepage, you’re designing a system that builds a thousand pages,” Yauhen says. “That’s the difference between a pretty site and a strong one.”
This also makes the development process smoother. Components can be independently tested, optimized, and reused across templates. It reduces redundancy, speeds up development, and ensures a consistent look and feel across the platform.
For clients looking to create a custom Drupal theme that still stands the test of time, this pattern-based approach remains a smart investment.
Performance isn’t something you can “tack on” at the end of a build. By the time you notice the site feels sluggish, it’s often too late to fix it without rewriting major parts of the theme. That’s why performance needs to be treated as a primary concern, right from the very first design decision.
In Drupal, your theme plays a central role in how efficiently your site performs. It governs everything from how assets are loaded and images are rendered to how layout shifts impact perceived speed. Done well, the theme sets the stage for fast, fluid interactions. Done poorly, it introduces friction that degrades user experience, even if the backend is flawless.
According to Yauhen, Drupal offers a lot under the hood: caching, lazy loading, and asset libraries. But those tools won’t save you if the theme is bloated from the start.
He explains, “If you’re loading five fonts, a full icon library, and four JavaScript frameworks in your theme, you’ve already lost. Build only what you need. That’s how you win.”
Theming decisions determine whether your site loads in one second or four, whether Google ranks it higher or penalizes it, and whether users stay or bounce.
That’s why we approach every theme with a performance-first mindset. Asset loading is carefully planned — only essential scripts and styles are included. Fonts are subset, compressed, and preloaded for maximum speed. Images are optimized not just for file size, but for contextual display — using responsive markup to serve the right size at the right time. Animations are considered critically: do they enhance the user experience, or just add overhead?
We also ensure that our themes work well with Drupal’s caching layers. By writing clean, modular templates and avoiding unnecessary logic in the front end, we help the CMS do its job more efficiently.
This level of discipline pays off — not just in numbers, but in how people feel when they use the site.
The phrase “mobile-first” is thrown around a lot, but few themes truly follow the philosophy. A responsive site isn’t necessarily mobile-first. True mobile-first design means starting with the smallest screen in mind and building up from there.
“We treat mobile as the default. If it works there, it’ll work everywhere else. But if you start with a desktop, you’ll always be fixing breakpoints,” Yauhen warns.
In practical terms, this affects layout choices, font sizes, image loading, and interaction design. It also directly impacts conversion rates and bounce rates.
No matter what kind of website you’re building — a corporate portal, an online store, or a media platform — the principle remains the same: mobile-first isn’t just a design trend, it’s a real user expectation.
When mobile UX is business-critical, we recommend specialized Drupal mobile development to ensure your stack, caching, and theming strategy are aligned.
One of the most overlooked parts of theming is the editorial workflow. While most attention goes to the frontend, the way editors interact with the CMS can have just as much impact on business outcomes.
If your theme makes editing frustrating, with poor preview support, rigid templates, or inaccessible UI patterns, your content team will slow down. And that slows down your campaigns, your SEO, your updates.
“An editor should feel confident, not scared, when using the site,” says Yauhen. “That’s what we aim for — themes that empower the team, not just impress the users.”
That’s why we build our custom themes to work with well-known Drupal tools like Layout Builder and Paragraphs — and extend them through our own Attico Platform. We test editing flows alongside frontend UX to make sure the experience feels smooth on both ends of the screen.
Whether you’re creating a Drupal theme for a public site or an internal platform, the editor experience matters just as much as the user-facing one.
A custom theme isn’t “done” when the site launches. It lives on. So we test it like a product, not a design.
That includes load testing, accessibility audits, SEO checks, real-device testing, and editorial workflow validation. We also document the theme structure — file paths, component names, best practices — so future developers can jump in easily.
“A theme without documentation is like a building without blueprints,” Yauhen adds. “It works for a while, then someone opens the wrong door and everything falls apart.”
We encourage clients to think of the theme not as a static asset, but as part of their product infrastructure. It should grow, evolve, and stay clean over time.
That’s true whether you’re launching a new Drupal platform or upgrading an existing one, because good maintenance starts with clarity.
At the end of the day, theming is not just a technical exercise. It’s a strategic one. It impacts how fast your site loads, how easy it is to update, how well your brand is represented, and how users perceive your business.
“If you think of your theme as just a wrapper for content, you’re missing the point,” Yauhen concludes. “It’s your frontend architecture. It’s how your business shows up online.”
So take the time. Ask the right questions. Work with a team that thinks about the big picture — and builds themes that go beyond aesthetics.
If you’re looking to launch a new Drupal project or rework your frontend — whether you’re exploring how to build a Drupal theme for the first time or need to create Drupal theme components at scale — let’s talk. We’ve helped dozens of teams design themes that serve users, editors, and business goals alike.