Web Development with WebStencils

Many Delphi and C++Builder teams want a modern web front end, but do not want to rewrite decades of trusted business logic in JavaScript frameworks that change every year.

WebStencils in RAD Studio gives you a clean, template-driven way to build modern, interactive web experiences directly from your existing Delphi or C++Builder server code, using familiar WebBroker or RAD Server projects.

Why WebStencils is compelling for existing Delphi codebases

Upgrading to a RAD Studio version that includes WebStencils turns your existing skills and code into a modern web delivery platform with the speed and security of native compiled code.

• Reuse proven business logic Keep your validation, workflows, and data access in Delphi/C++Builder. WebStencils simply turns the results into clean HTML.
• Modern UX without a front-end framework lock-in Use any CSS framework (Bootstrap, Tailwind, etc.) and JavaScript libraries you prefer, or combine WebStencils with HTMX for rich, dynamic behaviour with minimal JavaScript.
• Fast, server-side rendering Pages are rendered on the server, which keeps SEO-friendly HTML, predictable performance, and easier debugging than client-heavy Single Page Applications (SPAs).
• Clean separation of layout and logic Web designers can work on HTML/CSS templates, while Delphi developers focus on data and behaviour using WebStencils’ simple @ and { } syntax.
• Low-risk modernization path Start by adding a small web surface area (admin portal, reporting dashboard, simple self-service pages) on top of your existing application, then expand over time.

WebStencils + HTMX: modern interactivity, Delphi-first

WebStencils is a template engine that understands your Delphi objects, datasets, and sessions. HTMX adds modern interaction patterns directly in HTML:

• HTMX handles the browser side Add attributes to your HTML (such as hx-get, hx-post, hx-swap) to make parts of the page update dynamically without full reloads.
• WebStencils handles the server side Use expressions like @dataset.FieldName, @if (...) { ... }, @foreach dataset { ... } and layout constructs like @LayoutPage / @RenderBody to generate HTML fragments or full pages from your RAD Server or WebBroker actions.
• Ideal for incremental upgrades Start with simple, server-rendered navigation pages. Then progressively enhance sections with HTMX for live grids, inline editing, or dashboards, still powered by Delphi.

Typical modernization journeys with WebStencils

1. Add a web portal on top of an existing system

• Expose the most-used workflows from your desktop app as web pages (for example, customer self-service, reporting, or approvals).
• Use WebStencils templates to render lists, details, and forms directly from your existing business logic.
• Add HTMX for partial page updates so users enjoy a responsive experience without learning a SPA framework.

2. Standardise server-rendered HTML

WebStencils gives you a maintainable way to produce HTML from Delphi regardless of how you got here. In practice you might be replacing hand-maintained markup, tidying up after years of small fixes, or moving on from older approaches (for example CGI/ISAPI handlers or server-side scripts that are hard to evolve).

With shared templates you can:

• Separate layout, data binding, and conditional logic cleanly.
• Introduce a consistent shell using @LayoutPage and @RenderBody.
• Use @ExtraHeader for page-specific CSS or JavaScript while keeping one base layout.

3. Deliver new REST + HTML experiences with RAD Server

RAD Server already gives you a strong REST-oriented server story. WebStencils fits alongside it when you also want browser-delivered HTML:

• The same RAD Server module can expose both JSON endpoints and HTML responses, so operators and integrators are not two unrelated codebases.
• WebStencils scaffolding and dataset-oriented templates help you build list, detail, and form-style pages quickly on top of data you already surface from Delphi.

Architecture at a glance

At a high level, a WebStencils-based web application looks like this:

• RAD Studio server application (WebBroker or RAD Server) hosts your modules, business logic, and data access.
• TWebStencilsEngine / TWebStencilsProcessor components load HTML templates, merge them with your objects, datasets, and session data, and output HTML.
• HTMX-enhanced HTML in the browser calls back into REST endpoints or WebStencils-powered actions for partial updates.

This keeps server-side logic in Delphi/C++Builder, where your team already has deep expertise, and presentation in HTML, CSS, and lightweight browser tools that designers and frontend-minded developers can own.

Learn more and see it in action

If you would like help mapping your specific project to a WebStencils-powered architecture, use the “Talk to a specialist” button on this page to discuss your upgrade path and first web deliverables.