melange-nextjs-example

A minimal Next.js app where route files are written in Reason and compiled with Melange via Dune.

Stack

• Next.js App Router
• Melange + Dune (using melange 1.0)
• Nix dev shell (based on nix-ocaml/nix-overlays)
• Existing Next.js bindings from next/next.re

How it works

• Dune compiles .re files from app/ into JavaScript (dune build @melange).
• melange.emit writes generated Next artifacts, with promotion handled by Dune auto-promote.
• process-compose runs npm install first, then starts Next after install succeeds.
• Generated page modules are promoted into the source app tree (for example app/page.js).
• process-compose runs the Dune watcher and Next dev server together.
• Next.js runs from the project root.

Commands

make dev

Then open http://localhost:3000.

make dev is one-click:

• outside Nix: it enters nix develop automatically and starts process-compose.
• inside Nix: it runs process-compose directly.
• process-compose runs npm install first, then starts dependent processes.

For production build:

make build
make start