Build log · 4–26 Oct 2026 · from git
First commit to production in 16 days
In 23 days MirrorCut shipped a timeline editor, a 4K render pipeline, an agent that edits from chat, billing, a Mac app and the public launch. Every feature below is in the order it shipped, with how it's built, straight from the git history. Scroll to move the playhead, or press play.
- first commit to production
- 16 days
- features shipped
- 35
- commits
- 840
- commits a day, every day
- 36.5
- lines of code
- 160k
- test files
- 307
- apps and shared packages
- 4 + 9
- commits on the busiest day
- 90
Every feature, in order
What shipped, the day it started, and the technology underneath.
Editor· to 5 Oct
The editor and the Edit Plan
A timeline editor where every edit, by hand or by the agent, is one reviewable change.
- The whole edit is one typed document, the Edit Plan, shared by the web app, the API and the Python worker
- Changes are version-checked changesets, so two writers never overwrite each other
- Autosave, undo and redo on the same changesets
TurborepoTypeScriptZodNext.jsZustand
Billing
Accounts
Sign-up, log-in and settings from the first day.
- Email and password auth with sessions
- Profile and password change in Settings
Better AuthPostgresPrisma
Web + SEO· to 5 Oct
Landing page
A prompt-first homepage with live example cards.
- Hero motion drawn procedurally, no stock footage
- Shared type scale and buttons across the site and auth pages
Next.jsTailwind CSS
Media + render
Uploads and the media pipeline
Upload a recording and it plays in the editor within moments.
- Multipart uploads straight to S3, probed on completion
- Proxy, poster and waveform jobs on a Redis queue, their lifecycle kept in Postgres
- Transcription with word timings, so the agent can cut on words
S3BullMQRedisffmpegAssemblyAI
AI agents
Model router and Mice, the agent
One agent, Mice, that edits from chat and asks before it spends.
- A model registry and router with fallbacks, a call log and admin controls
- Versioned system prompts with output schemas and injection-safe rendering
- ask_user and confirm_generation enforced by the server, with a cost estimate first
OpenRouterNestJSZod
Media + render
Motion engine and 4K export
Designed graphics that look the same in the preview and the export, up to 4K.
- One scene renderer runs in the browser and on the server
- Decode, draw and encode overlap on worker threads; hardware H.264 chosen by a test encode
- A 22-second 4K export went from 129 s to 40 s; sound normalised to -14 LUFS
@napi-rs/canvasffmpegVideoToolbox / NVENCMediabunny
AI agents
Intent, research and design agents
Mice understands the request, researches current editing style and calls a motion design team.
- An intent agent reads the request before anything is edited
- A research agent brings back live sources
- A motion critic watches the real rendered motion and asks for one revision
ClaudeGPTGemini
AI agents
Auto-Edit and stock B-roll
An AI rough cut that follows the script and the emotion, with licensed B-roll.
- The planner reads every take as numbered words and returns the cut as word ranges
- Code checks the plan, paces silences by emotion and keeps the beats
- Scored 99/100 on the test cut against 50 for the plain agent, about $0.10 a run
Claude OpusWikimedia CommonsNASA
Editor
Graphics library
200 templates: lower thirds, titles, stats, quotes, charts, social and end cards.
- Shipped in four drops in one day
- Every template is data for the motion engine, so it restyles to the video's fonts and colours
graphics-kitmotion-engine
AI agents
Colour, looks and guided editing
Mice balances every camera and offers a look, then guides each video type step by step.
- HDR and log footage handled, brand-safe looks
- Cuts land on the music's beats
- Playbooks per video category
ffmpeg
Billing
Plans and checkout
Paid plans with an in-app checkout.
- A plan is required before the app
- Checkout in a dialog, webhooks settle the subscription
Stripe
AI agents· to 10 Oct
The Director and house style
A Director that assembles the whole video, critiques it and reports what it did.
- Assemble, critique, report, measure
- A music bed set from measured loudness, speaker cut-outs reused across runs
- House type, 100 colour schemes and reference graphics
ONNX RuntimeClaude
Media + render
Mac app
A native Mac window onto the web app, so every web deploy reaches it with no release.
- Window locked to the web origin, a typed and versioned bridge
- Native saving, notifications, uploads kept alive and a local media cache
Electronelectron-updater
Editor
Exports you can trust
Progress you can see, cancel that really stops, and retry for anything that fails.
- No media job waits forever
- A cancelled export stops its worker
- Originals fetched once and cached
BullMQ
AI agents· to 12 Oct
Reference library and layout rules
Videos styled from a library of reference grammars, with text that never covers a face.
- The style card offers three grammars and every worker follows the chosen one
- Stock cutaways matched to what is said, icons as the fallback
- A graphic that can't clear a face moves beside the speaker
Face detectionStock search
Launch + ops· to 14 Oct
CI and deploys
Every change goes through checks and a smoke test before deploy.
- Lint, types and tests on every pull request
- Image artifacts cleaned up after each run
GitHub ActionsDocker
Editor
New editor layout and the Design panel
An icon rail with one panel at a time, Mice in its own column, and the video's fonts and colours by hand.
- Brand fonts in the editor, the type and the export
- 1,918 open-licence Google Fonts to browse and add
- Redo saves with a fresh changeset id
Reactfontkit
Media + render
HTML render service
Scenes written in HTML become clips on the timeline.
- A headless render service turns HTML scenes into video
- The designer can write HTML, and both kinds of scene compete for a hero moment
HyperFramesGSAPthree.js
Billing· to 14 Oct
Trial, email and the Studio plan
A free trial, transactional email, verified accounts and three plans.
- Trial paywall, sign-up and rate limits
- Email verification required
- Studio above Pro
ResendStripe
AI agents
Generated shots and explainer Shorts
When stock can't show it, Mice generates the shot, and Shorts are cut at a pro editor's rhythm.
- A still in the video's look, then animated and checked like stock
- Only after the creator agrees on the storyboard card
- Prices set so generated video keeps its margin
Gemini Flash ImageHiggsfield
Web + SEO· to 16 Oct
SEO foundation
The site goes on Google with honest pricing and comparison pages.
- Audit fixes: accurate claims, self-hosted fonts, a static homepage
- Search Console verified
- Pricing built from the real plan catalogue, comparisons checked against competitors' own pages
Next.jsschema.orgSearch Console
Launch + ops
HTTPS hardening
HSTS on the web server.
- One-year HSTS
Caddy
Web + SEO· to 18 Oct
Speed and accessibility
A faster homepage and an accessibility score of 100.
- Heavy modules kept out of the first JavaScript, the hero paints at once
- Analytics loaded after the page
- Contrast and link names fixed
Lighthouse
Media + render
Voice cleaning
Cleaner speech from any microphone.
- Audio filters in the preview and the export
ffmpeg
Launch + ops
Directory submission kit
Listing copy, pricing, links and screenshots ready for directories.
- One source of brand facts for every listing
Docs
AI agents
Brand ads
Mice makes a designed ad for any brand from its website, logo or product screens.
- Ads arrive as editable scenes on the timeline
- A sound for each kind of moment, on its frame
- A failed ad gives the credits back
Puppeteermotion-engine
Launch + ops· to 19 Oct
Security review and first release
A full-project review before the first production release.
- No lost edits, honest refunds, enforced upload sizes, backups
- Workflows documented, production branch merged
Code reviewSecurity review
Web + SEO· to 21 Oct
Legal pages and answer-engine SEO
Terms, privacy and child safety published, and every guide answers its question first.
- A quick answer and a named author on every guide
- Watch pages for every example ad
- Comparisons with CapCut and VEED
schema.orgllms.txt
Billing
Privacy controls
Delete your account any time, and AI that never trains on your videos.
- Delete account in Settings with a confirm link
- AI requests routed only to providers that don't store or train on data
- 18+ confirmation at sign-up
OpenRouter
Launch + ops· to 21 Oct
Launch kits
Product Hunt kit, brand facts and a community reply kit.
- A local pre-push check that runs what CI runs
Docs
Launch + ops
Production safety
Errors reach the team before users report them.
- Browser errors reported, real error and 404 pages
- Export concurrency setting, priority renders
Next.js
AI agents· to 24 Oct
The ad kit
Ads from a screen recording or straight from the App Store and Google Play.
- Designer transitions, hook openings and end-card looks
- Full-screen, 3D device and close-up product scenes
- 82 reference cards from 100 brands' ads; each ad reads the five nearest
GSAPiTunes Search APIGoogle Play
Web + SEO· to 24 Oct
Search pages and free tools
Pages for the searches creators make, and free tools they can use today.
- Best AI video editors, AI video editor for YouTube, long video to Shorts
- llms.txt and FAQ kept in step with the product
Next.js
Billing
Credits and cost tracking
Every AI call is costed and charged from a credit ledger.
- Cost tracking per call
- Refunds settled from the ledger
Postgres
AI agents· to 26 Oct
Ad scorecard, product and story checks
Every ad is measured against real product-led ads before anyone sees it.
- Motion, cuts, contrast, brightness and product share measured against ten real ads
- A product check so the product is never shown broken: faults went from 14 to 0
- Story checks before render, three story options and a critic
MeasurementClaude HaikuHyperFrames
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Start your free trialSource: the git history of the MirrorCut repository, first commit 4 Oct 2026, last updated 26 Oct 2026. 799 of the 840 commits are by co-founder Sagar Dey. Lines of code are tracked TypeScript, JavaScript and Python files; production is the first release to the production branch on 19 Oct. About MirrorCut