Introduction

Mizu is a lightweight web framework for Go. The name means “water” in Japanese, reflecting the framework’s goal: to flow naturally with Go’s standard library rather than replacing it.

What is Mizu?

Mizu helps you build web servers and APIs in Go. If you’ve used Python’s Flask, Node’s Express, or Ruby’s Sinatra, Mizu fills a similar role but stays closer to how Go works. A web framework handles the repetitive parts of building HTTP servers:

Routing: Matching URLs like /users/123 to your code
Request handling: Reading data from forms, JSON bodies, and URLs
Response writing: Sending back JSON, HTML, or files
Middleware: Running shared code (logging, auth) before handlers

What makes Mizu different?

Mizu adds a thin layer over Go’s net/http package instead of replacing it:

Feature	What it does	Why it matters
Go 1.22 ServeMux patterns	Routes like `/users/{id}` with path parameters	Uses the standard library, not a custom router
Context wrapper	`c.JSON()`, `c.Query()`, `c.Param()` helpers	Less boilerplate, cleaner handlers
Error returns	Handlers return errors directly	Central error handling, simpler code
Graceful shutdown	Finishes active requests before stopping	Safe deployments without dropped connections
Structured logging	Uses Go’s `slog` package	JSON logs for production, readable logs for development

Everything stays explicit. There is no reflection, code generation, or hidden behavior. If you know Go’s net/http, you already understand how Mizu works.

Who is Mizu for?

Mizu is a good fit if you:

Know Go basics and want to build web APIs
Prefer explicit code over “magic” conventions
Want to use standard library patterns, not framework-specific ones
Need a small, focused tool rather than a full-stack framework

Mizu is not for you if you want an opinionated framework with ORM, admin panels, and auth built in. For those needs, consider frameworks like Buffalo or Beego.

A quick taste

Here’s a complete Mizu server in 15 lines:

package main

import "github.com/go-mizu/mizu"

func main() {
    app := mizu.New()

    app.Get("/", func(c *mizu.Ctx) error {
        return c.Text(200, "Hello, Mizu!")
    })

    app.Get("/users/{id}", func(c *mizu.Ctx) error {
        id := c.Param("id")
        return c.JSON(200, map[string]string{"user_id": id})
    })

    app.Listen(":3000")
}

When this runs:

Visiting http://localhost:3000/ returns “Hello, Mizu!” as plain text
Visiting http://localhost:3000/users/42 returns {"user_id":"42"} as JSON
Pressing Ctrl+C stops the server gracefully

Get started

Quick Start

Build your first app in five minutes.

Why Mizu

Understand the design philosophy.

Features

See what Mizu provides.

Concepts

Learn how routing, handlers, and middleware work.

Overview

Getting Started

Core Concepts

Building Your App

Deployment

Learn More

What is Mizu?

What makes Mizu different?

Who is Mizu for?

A quick taste

Get started

Quick Start

Why Mizu

Features

Concepts

​What is Mizu?

​What makes Mizu different?

​Who is Mizu for?

​A quick taste

​Get started

Quick Start

Why Mizu

Features

Concepts

What is Mizu?

What makes Mizu different?

Who is Mizu for?

A quick taste

Get started