Spark.NET is a full stack framework. Because of this, we recognize that you not only need a backend but also a frontend as well.

Spark gives you two project options to build your frontends with.

  • Blazor SSR
  • Razor Pages

Blazor SSR

Blazor utilizes Razor components to split your markdown into re-usable chunks. These components also have the ability to contain logic specific to themselves and can even have url routes invoke them.

@page "/developers"
@inject DeveloperService developerService
@code {
    private List<Developer> developers { get; set; }
    protected override void OnInitialized()
        developers = await developerService.GetDevelopers();

    @foreach (var developer in developers)

All Blazor SSR apps come with enhanced navigation, meaning any navigation or form submissions don’t require full page reloads, making your apps nice and snappy.

You can learn more on our Blazor page.

Enhancing with HTMX

You can also swap out the out of the box enhancements that come with Blazor for HTMX.

HTMX will provide the same enhanced navigation and form submissions by adding the hx-boost attribute to the body tag in your layout files and swapping the blazor.web.js script with the HTMX script.

<!-- MainLayout.razor -->

    <script src="" crossorigin="anonymous"></script>
<body hx-boost="true" class="bg-gray-100 flex flex-col min-h-screen">
    <NavBar />
    <main class="container py-20 px-4 md:px-12 max-w-6xl w-full mx-auto">
    <FlashMessages />
    @*<script src="_framework/blazor.web.js"></script> 👈 Remove this *@

HTMX adds other enhancements that the Blazor enhancements do not. Things such as:

  • Polling
  • Removing elements after x seconds
  • GET and POST triggers on elements

Razor Pages

Razor Pages utilizes the Razor Templating language to build server side rendered views with code behind files to run logic on GET or POST requests for that view.

For example, a simple home page for an app would look like the following.

<!-- Index.cshtml -->

@page "/"
@model Index

<h1>Hello @Model.Name</h1>

And the code behind…

// Index.cshtml.cs

public class Index : PageModel
    public string Name { get; set; }

	public void OnGet()
        Name = "World";

Enhancing with HTMX

HTMX is a quick way to enhance the feel of your Razor Pages application.

HTMX gives you the ability to use AJAX requests via HTML attributes. You can also utilize the hx-boost attribute in the body tag of your layout files. This will make any navigation or form submissions in your app utilize AJAX for partial page reloads, giving it a SPA like feel.

<!-- _MainLayout.cshtml -->

    <script src="" crossorigin="anonymous"></script>
<body hx-boost="true" class="bg-gray-100 flex flex-col min-h-screen">
    <partial name="_NavBar" />
    <main class="container py-20 px-4 md:px-12 max-w-6xl w-full mx-auto">
    <partial name="_FlashMessages" />

Enhancing with Hydro

Hydro is a framework for building Razor Pages apps that behave like dynamic and interactive JavaScript frontends like React.

Hydro, unlike HTMX, allows you to persist page state between HTTP requests. This makes it great for building rich, interactive UIs.

For example, a “Counter” component would look like the following:

// Counter.cs

public class Counter : HydroComponent
    public int Count { get; set; }
    public void Add(int value)
        Count += value;

And it’s corresponding razor template:

<!-- Counter.cshtml -->

@model Counter

  Count: @Model.Count
  <button hydro-on:click="@(() => Model.Add(1))">
    Add 1

By adding HTML attributes, like hydro-on:click above, you can tie actions in your markup to functions on your backend. This opens the door for .NET developers to build dynamic web applications while staying within the ASP.NET and C# ecosystem.


Spark projects come with Tailwind CSS and DaisyUI installed via NPM.

If you need to write custom CSS, you can do so in the Assets/Css/app.css file.

If you need to customize Tailwind CSS configuration, you can do so in the tailwind.config.js file.

If you need to add custom CSS classes outside of the Tailwind library, you can do so by updating the Assets/Css/app.css file. This file is picked up by Vite, which prunes any unused Tailwind classes and bundles a minified CSS file for you.

Bundling Assets

Spark uses Vite to bundle your CSS and JS for you. It provides fast build times and Hot Module Replacement during local development.

You will find a vite.config.js file that configures and loads Vite for you.

Spark also uses the Vite.AspNetCore Nuget package. This auto starts a Vite server for you when developing locally so you don’t have to start it manually.

Finally, Spark projects are also setup to build your assets for you whenever running a dotnet build or dotnet publish. You can find thses build commands in your .csproj file in the App folder.

Custom Javascript

If you need to write custom JavaScript, it is advised to do so in the Assets/Js/app.js file. This file is picked up by Vite, which then builds the minified Js file for you.