Comparison

Gastro is one of several approaches to building HTML with Go. This page compares Gastro with Templ, gomponents, htmgo, and Go's standard html/template package. Each has real strengths — pick the one that fits your project.

At a Glance

Syntax & Developer Experience

The biggest difference between these tools is how you write HTML. Here's the same component — a greeting card — in each approach.

Gastro

A .gastro file with Go frontmatter and html/template markup. If you know HTML and Go, you can read it immediately:

---
type Props struct {
    Name    string
    IsAdmin bool
}

p := gastro.Props()
Name := p.Name
IsAdmin := p.IsAdmin
---
<div class="greeting-card">
    <h2>Hello, {{ .Name }}</h2>
    {{ if .IsAdmin }}
        <span class="badge">Admin</span>
    {{ end }}
</div>

Templ

A custom DSL in .templ files. Looks like Go with embedded HTML, compiled to Go code:

templ GreetingCard(name string, isAdmin bool) {
    <div class="greeting-card">
        <h2>Hello, { name }</h2>
        if isAdmin {
            <span class="badge">Admin</span>
        }
    </div>
}

gomponents

Pure Go functions that build an HTML node tree. No templates, no code generation:

func GreetingCard(name string, isAdmin bool) g.Node {
    return Div(Class("greeting-card"),
        H2(g.Textf("Hello, %s", name)),
        g.If(isAdmin,
            Span(Class("badge"), g.Text("Admin")),
        ),
    )
}

htmgo

Pure Go functions similar to gomponents, designed around htmx patterns:

func GreetingCard(name string, isAdmin bool) *h.Element {
    return h.Div(
        h.Class("greeting-card"),
        h.H2(h.TextF("Hello, %s", name)),
        h.Iff(isAdmin, func() *h.Element {
            return h.Span(h.Class("badge"), h.Text("Admin"))
        }),
    )
}

html/template

Go's standard library. Templates are parsed at runtime from strings or files:

// Template file: greeting-card.html
<div class="greeting-card">
    <h2>Hello, {{.Name}}</h2>
    {{if .IsAdmin}}
        <span class="badge">Admin</span>
    {{end}}
</div>

// Go code to render:
type GreetingData struct {
    Name    string
    IsAdmin bool
}
tmpl.ExecuteTemplate(w, "greeting-card.html", GreetingData{
    Name: "Alice", IsAdmin: true,
})

Type Safety

Type safety determines when you catch errors — at compile time or at runtime.

• Gastro generates Go code with typed Props structs. If you pass the wrong type to a component, the Go compiler catches it. Template expressions ({{ .Name }}) are still checked at parse time but not at compile time.
• Templ compiles .templ files to Go. Component parameters are regular Go function arguments — fully type-checked by the compiler. Expressions inside templates are also compiled to Go, giving end-to-end compile-time safety.
• gomponents and htmgo are native Go code. Everything is type-checked by the compiler. There are no templates at all — HTML structure is Go function calls.
• html/template passes data via interface{}. Misspelled field names, wrong types, and missing data are only caught at runtime.

File-based Routing

File-based routing maps filesystem paths to URL routes automatically, reducing boilerplate.

• Gastro — files in pages/ become routes automatically. pages/blog/[slug].gastro becomes GET /blog/{slug}. Dynamic parameters use bracket syntax. No manual route registration needed.
• htmgo — similar file-based routing. Pages in a designated directory are registered automatically. Supports dynamic segments.
• Templ, gomponents, and html/template — you wire routes manually using http.ServeMux, Chi, Echo, Gorilla, or any Go router. This is more flexible but requires more boilerplate.

Build & Tooling

Deployment

All five approaches produce a single deployable binary. The differences are in how assets are embedded:

• Gastro — templates and static assets are embedded via go:embed at build time. One binary, zero runtime dependencies.
• Templ — templates are compiled directly into Go code. No template files to embed. Static assets still need go:embed or an external CDN.
• gomponents — HTML is generated by Go code, so there are no template files at all. Static assets need separate handling.
• htmgo — assets (including built CSS) are embedded into the binary. Built-in Tailwind CSS processing.
• html/template — templates can be embedded with go:embed. Everything else is manual.

Learning Curve

Ecosystem & Maturity

When to Choose What

• Gastro — you want file-based routing, HTML-first syntax with Go's type safety, built-in SSE support, and a single CLI that handles the full dev-to-deploy workflow.
• Templ — you want the strongest compile-time type safety, mature tooling with IDE integration, and don't mind learning a custom DSL.
• gomponents — you want zero code generation, zero new syntax, and prefer building HTML entirely in Go functions.
• htmgo — you want a batteries-included framework with HTMX integration, file-based routing, and built-in Tailwind support.
• html/template — you want zero dependencies, are comfortable with runtime-only type checking, and prefer the standard library.