# Build brief — a focused alternative to Subclip > **Verdict:** Not faithfully · **Buildability:** 22/100 · **Category:** Audio Video > **Source:** https://www.canitbevibecoded.com/subclip > Independent editorial assessment from Can It Be Vibe Coded? Not affiliated with, endorsed by, or derived from Subclip. Verify current pricing and capabilities before acting. ## Context **Subclip** — AI platform for clipping, transcript editing, captions, dubbing, rendering, and publishing. It currently costs $14/mo. Subclip is not a realistic vibe-coded replacement. A narrow transcript cutter is buildable, but the product is a multi-surface post-production system: ONNX models running locally in the browser, client-side and server-side Remotion rendering, cloud AI and media jobs, native macOS and iOS experiences, plus an MCP server and developer APIs. Reproducing and operating those surfaces is a platform project, not a one-shot build. This brief describes a focused, single-operator replacement for the part of Subclip 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 Build only the closest consolation: import a video, transcribe it locally, cut by editing the transcript or removing silence, style subtitles, and export an MP4 and SRT. - Transcribe supplied recordings, cut them on a timeline, and export finished files. - A responsive interface with real empty, loading, success, and error states. ## Requirements ### Functional - Python 3.12. - FFmpeg. - Faster-whisper. - Desktop with enough storage for source media and renders. - GPU optional. ### 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 the closest honest personal substitute for Subclip, not a platform clone. Requirements: - Use Python 3.12 + FastAPI for a localhost web app, with a plain JavaScript frontend, FFmpeg for media work, and faster-whisper for word-level transcription. - I can import MP4, MOV, WebM, MP3, or WAV files, see a synced transcript beside the video preview, and click any word to seek to its timestamp. - Deleting transcript ranges creates an undoable cut list. Detect silences longer than 500 ms and let me accept or reject each suggested cut before rendering. - Let me edit subtitle text and timing, import or export SRT, and apply one ASS style file with font, colors, outline, position, and words-per-line controls. - Export MP4 in 16:9, 9:16, or 1:1 with center-crop or blur-pad. Never overwrite the source, and show FFmpeg progress plus a useful failure message. - Store projects as JSON under ~/SubclipDIY/projects and renders under ~/SubclipDIY/exports, with a recent-projects page and a delete-project action. - Bind to localhost only. No accounts, uploads, telemetry, or network calls after the faster-whisper model has been downloaded. - Deliberately exclude ONNX models in the browser, Remotion client or server rendering, native apps, cloud dubbing, render queues, publishing, an MCP server, and public APIs. - Add unit tests for cut-list merging and subtitle grouping, plus one smoke test that imports a short fixture and produces a playable MP4. - Include a README with setup for Python and FFmpeg, model-size guidance, data paths, supported formats, and an honest warning about CPU transcription and render speed. ## 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: - ONNX model packaging and hardware-accelerated in-browser inference. - Coordinated client-side and server-side Remotion rendering. - Native macOS and iOS apps and their release pipelines. - Production dubbing, voice cloning, storage, and render queues. - MCP server, developer APIs, NLE exports, and publishing integrations. ## 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. - Maintain every third-party integration as APIs and OAuth rules change. ## Risk **Operational risk.** The code is achievable; dependable data, integrations, and ongoing operations are the real cost. Editorial confidence in this assessment: high. No reviewed project implementation is linked yet. ## Prior art Working open-source software you can read, fork, or borrow from before starting: - [Lightweight Video Editor](https://github.com/proSamik/lightweight-video-editor) — Open-source Electron editor with local Whisper transcription, word-level caption editing, clipping, and FFmpeg export --- Generated by [Can It Be Vibe Coded?](https://www.canitbevibecoded.com) · Full report: https://www.canitbevibecoded.com/subclip