Can AudioFetcher be vibe coded?

Build brief — a focused alternative to AudioFetcher

**Verdict:** Partly, if you narrow it · **Buildability:** 72/100 · **Category:** Audio Video

**Source:** https://www.canitbevibecoded.com/audiofetcher

Independent editorial assessment from Can It Be Vibe Coded? Not affiliated with, endorsed by, or derived from AudioFetcher. Verify current pricing and capabilities before acting.

Context

**AudioFetcher** — Paste a YouTube or playlist link, convert to MP3, and download · Pro adds 320 kbps and priority queue. It currently costs $6/mo.

The core loop is genuinely one-shottable: a small local UI, yt-dlp for the fetch, ffmpeg for the encode, files land in a folder. What is not simple is everything that makes a public converter feel reliable week after week · YouTube bot checks, cookies/PO tokens, geo blocks, fair queues, abuse protection, and a hosted path so non-technical people never open a terminal. Build the personal script; do not expect one prompt to replace a maintained public service.

This brief describes a focused, single-operator replacement for the part of AudioFetcher that is genuinely reproducible. It is deliberately narrower than the product it replaces, and it says so in writing. Build the useful core; do not pretend to have rebuilt the rest.

What you are building

Accept a YouTube URL or playlist, download audio with yt-dlp, encode MP3 with ffmpeg, and save the file locally.

Build a focused single-user workflow with real persistence, search, and export.

A responsive interface with real empty, loading, success, and error states.

Requirements

Functional

Python or Node.

Yt-dlp.

Ffmpeg.

Optional cookies or residential proxy if YouTube blocks datacenter IPs.

Non-functional

Accessibility: semantic markup, labelled controls, visible focus, and reduced-motion support.

Security: server-side secrets, validated input, and no credentials in the client bundle.

Reliability: retries with backoff on external calls, and a clear failure state when a provider is down.

Portability: the operator can export their data and leave without losing it.

Implementation brief

Build me a personal YouTube-to-MP3 tool to replace AudioFetcher for one user on my laptop. Requirements:

Python 3.11 + a tiny localhost Flask or Starlette app; one page with a URL field,

quality select (128 / 192 / 256 / 320 kbps), and a Convert button.

On submit, shell out to yt-dlp to pull best audio only, then ffmpeg to CBR MP3 at the

chosen bitrate. Write files into ./downloads with a safe title filename.

Support a single video URL and a playlist URL. For playlists, show a checkbox list of

titles first (yt-dlp --flat-playlist --print), then convert only checked items one by one

with a simple progress log on the page (SSE or polling).

Put YT_COOKIES_FILE and optional HTTP_PROXY in .env; pass them to yt-dlp when set.

If yt-dlp returns LOGIN_REQUIRED or bot-check text, show that error plainly and tell me

to export cookies from a logged-in browser.

Cap each job at 3 hours of media; reject live streams. No accounts, no cloud, no queue

service for other users · this is just me.

Out of scope: multi-tenant fair queues, Stripe/Pro billing, magic-link auth, public

abuse protection, mobile apps.

README: install yt-dlp + ffmpeg, how to export Netscape cookies, and a blunt note that

YouTube blocks many datacenter IPs so a home machine or cookies may be required.

Delivery standard

Inspect the repository first, then write a short implementation plan before writing code.

Deliver the smallest complete end-to-end workflow first; every primary control must work against persisted data.

Use real validation and storage; never substitute fake dashboards, decorative controls, hard-coded success states, or mock integrations.

Include responsive layouts plus genuine empty, loading, success, validation, and failure states.

Keep secrets server-side in environment variables, provide .env.example, and never commit credentials or user data.

Add structured logs around every external call and return actionable errors without leaking sensitive details.

Write unit tests for the core logic and one automated test of the main user journey.

Finish with a README covering setup, architecture, data location, backups, tests, deployment, and known limitations.

Acceptance criteria

A clean install starts the app using only the README and .env.example.

The primary journey works from first visit through saved result, reload, edit, export, and deletion where applicable.

Invalid input, missing configuration, provider failure, and an empty database each have a usable state.

The interface works at 390px and 1440px, is keyboard navigable, and shows visible focus on every control.

Tests, type checking, linting, and a production build all pass with no ignored failures.

No part of the interface implies a live integration, security guarantee, or scale capability that was not actually built and verified.

Non-goals

Do not build these, and do not claim to have replaced them:

Hosted UI for non-technical users.

Playlist preview with per-track checkboxes.

Priority queue and 320 kbps Pro path.

Someone else fighting YouTube bot checks, PO tokens, and geo blocks.

The last 20 percent is sync, migration fidelity, speed, and edge cases.

What you still own after launch

Run migrations, backups, restores, and dependency updates.

Test the critical journey after every model, API, or hosting change.

Monitor failures and fix the edge cases a first prompt will miss.

Risk

**Manageable.** A personal version is realistic if you test the critical journey and keep reliable backups.

Editorial confidence in this assessment: high. No independent one-shot implementation is linked yet.

Prior art

Working open-source software you can read, fork, or borrow from before starting:

[yt-dlp](https://github.com/yt-dlp/yt-dlp) — The actual download engine almost every converter wraps. Best DIY path is using it directly

[cobalt](https://github.com/imputnet/cobalt) — Open-source multi-service media downloader with a self-hostable API and web UI

[youtube-dl](https://github.com/ytdl-org/youtube-dl) — Older predecessor; still useful context for how long this cat-and-mouse has run

Generated by [Can It Be Vibe Coded?](https://www.canitbevibecoded.com) · Full report: https://www.canitbevibecoded.com/audiofetcher