Build an Audio Editor Online with Claude Code

Build an Audio Editor Online web app. People search for "audio editor online" about 30,000 times a month, plus related searches like "edit audio online free", "online audio editor", "web audio editing tool". The goal is a tool that ranks for those searches and makes money.

What it should do:
Build an online audio editor web app. Create a homepage with audio upload or microphone recording options. Build a waveform editor with multi-track support, zoom controls, and selection tools. Add effect panels for reverb, echo, equalizer, and noise reduction. Include basic editing tools: cut, copy, paste, fade in/out, and volume adjustment. Show playback controls with loop and speed adjustment. Add export options for different formats (MP3, WAV, FLAC) and quality settings. Use a dark theme with blue/purple audio-focused colors. Focus on the waveform editing and basic effects first.

How to build it:
1. Read this folder first. If it is empty, set up Next.js (App Router, TypeScript, Tailwind). Write a short PLAN.md with the pages, components, any library or API you need, and what you are leaving for later. Then build.
2. Put the tool itself on the homepage so a visitor can use it within seconds, with no sign-up. Do the processing in the browser where you can, so it is fast and cheap to run. Look at how TwistedWave Online, AudioMass, BandLab do it and make ours simpler and faster.
3. Make it rank. Use "audio editor online" in the title tag, H1 and meta description. Under the tool, add a short how-to and an FAQ with FAQPage schema, and add a sitemap and robots.txt. Scaffold these programmatic pages from one template and a data file: /audio-editor-for-[purpose], /edit-[audio-format]-online, /online-audio-[editing-feature].
4. Monetisation: Freemium: 5min tracks, $9/mo unlimited + premium effects. Add a pricing page and the free usage limit, and leave Stripe checkout as a clearly marked stub with the environment variables it needs.
5. Run it locally and test the main flow end to end, including edge cases like empty input and very large files. Fix what breaks, then finish with a summary of what works, what is stubbed and how to deploy it to Vercel.

Paste it into Claude Code in an empty folder. It plans first, so read PLAN.md and steer before it starts building.