Nex

The simplest way to build HTMX apps in Elixir

Nex is a minimalist, HTMX-first toolkit for building server-rendered Elixir apps fast.

Why Nex

Nex is built for developers who want to ship real products without dragging in SPA complexity or framework ceremony.

HTMX-first — server-rendered UX without a large frontend stack
Minimal API surface — one use Nex entry point for pages, APIs, and components
File-based routing — routes come from the filesystem, not route config
Fast iteration — hot reloading, simple project structure, and low boilerplate
AI-friendly locality — UI and behavior live close together, which makes the codebase easier for both humans and agents to modify

What Nex Is and Is Not

Nex is a pragmatic framework for:

indie products
internal tools and dashboards
HTMX-first web apps
JSON APIs and streaming endpoints
teams that want SSR with less complexity

Nex is not trying to be:

a Phoenix replacement for every use case
a batteries-included enterprise platform
the best fit for complex SPAs

Quick Start

mix archive.install hex nex_new
mix nex.new my_app
cd my_app
mix nex.dev

Then open http://localhost:4000. This default scaffold is the basic starter: the lightest way to learn Nex. Generated apps include AGENTS.md plus a project-local skill at .agents/skills/nex-project/SKILL.md for AI onboarding.

If you want the product starter with auth, database wiring, and a protected dashboard:

mix nex.new my_app --starter saas

Example Project Structure

my_app/
├── .agents/
│   └── skills/
│       └── nex-project/
│           └── SKILL.md
├── AGENTS.md
├── src/
│   ├── api/
│   │   └── todos/
│   │       └── index.ex
│   ├── components/
│   └── pages/
│       ├── _app.ex
│       ├── _document.ex
│       ├── index.ex
│       └── [id].ex
├── mix.exs
└── Dockerfile

Core Capabilities

Pages and Routing

File-based routing from src/pages/
Dynamic segments like [id], [slug], and [...path]
Convention-over-configuration module structure

HTMX and SSR

HTML-first rendering with HEEx templates
HTMX integration out of the box (Nex.HTMX helpers for triggering events, redirects, etc.)
Automatic CSRF handling for state-changing requests
Partial updates without SPA plumbing

APIs and Realtime

JSON APIs with a simple request object
Native SSE streaming with Nex.stream/1
WebSocket support for user-defined handlers
Shared request-time helpers for cookies, session, and flash

Developer Experience

Unified use Nex entry point
Low-boilerplate layouts and page modules
AGENTS.md bootstrap plus a project-local SKILL.md for AI assistants
Built-in static file serving
Example gallery and product-shaped apps in the same repository

Monorepo Map

Main Product Line: Nex

framework/ — the core Nex framework published as nex_core
installer/ — mix nex.new project generator
nex_base/ — schema-less database layer and query builder
examples/ — the Nex gallery, including focused patterns and larger app examples
website/ — the official site built with Nex itself

Start Here

If you want the fastest path into Nex, use this sequence:

Read this README
Start with mix nex.new for the default basic scaffold, or use mix nex.new --starter saas when you want the auth + database starter
Open one focused example
Open more of the gallery once the basics click

Example Gallery

Browse the gallery in examples/. The canonical example metadata now lives in examples/catalog.exs, which drives the website, CI matrix, and batch verification scripts.

A Tiny Example

defmodule MyApp.Pages.Index do
  use Nex

  def mount(_params) do
    %{count: Nex.Store.get(:count, 0)}
  end

  def render(assigns) do
    ~H"""
    <div>
      <h1>Counter</h1>
      <div id="counter-display">{@count}</div>
      <button hx-post="/increment" hx-target="#counter-display" hx-swap="outerHTML">+</button>
    </div>
    """
  end

  def increment(_req) do
    count = Nex.Store.update(:count, 0, &(&1 + 1))
    ~H"<div id="counter-display">{count}</div>"
  end
end

Nex