Nicekit

A whoami-class network diagnostic and a browser-only tools hub. Nothing identifying is stored.

Live: nicekit.vercel.app

Open / in a browser for the tool hub — it lists the who-am-I tile plus every file and web tool. Open /whoami for the card: your public IP, a Cloudflare speed test, your origin, the weather there, a best-guess VPN flag, the DNS resolver your browser used, and your browser/OS. curl the same URL and you get just the IP. Files processed by the tools never leave your machine.

The card (/whoami)

Every row is a live measurement or lookup against your actual exit path, not a cached sample.

Fact	How
Public IP (IPv4/IPv6)	x-real-ip, then x-vercel-forwarded-for, then the rightmost X-Forwarded-For hop (the leftmost is spoofable). Loopback or missing → egress lookup via ipify.
Origin	City, region, country, postal, coordinates, timezone, ASN, ISP from ipwho.is, plus the covering BGP prefix from RIPE Stat, plus postcode and gap-fills from ipinfo / ipapi.is.
Weather	Current conditions from Open-Meteo at the origin coordinates.
Local time	Origin timezone from the geo lookup.
DNS resolver	The browser's own resolver, probed client-side via an ip-api EDNS lookup of a random hostname. Reports your device's stub resolver, not the server's.
Speed	Cloudflare speed.cloudflare.com engine (@cloudflare/speedtest) run in your tab: download, upload, latency, plus advanced jitter/lag details.
VPN / proxy / Tor / hosting	Heuristic from ipapi.is, probed from the browser, with an honest disclaimer: lists miss many commercial and almost all residential VPNs; the network name is the org on the exit address, not a guaranteed product.
Browser / OS	User-Agent plus Client Hints (architecture, bitness, platform, model) requested via Accept-CH / Critical-CH.
Advanced facts	Languages, screen size, CPU cores, device memory, network type (Network Information API), clock skew vs the server, timezone match, reduced-motion, color scheme, bot flag. All client-side, never sent anywhere.
Reverse DNS	On demand at /hostname (1.5 s timeout, text/plain).
Visits	Anonymous total visit count and the set of country codes seen, via Upstash Redis. No IPs, no fingerprints.
Backdrop	Three.js earth horizon on desktop, light/dark theme toggle everywhere.

Tools (/)

Eight tools in two families, all listed as tiles on the home page. File tools run entirely in the browser — bytes never leave the tab. Web tools fetch public URLs through small server routes.

File tools (client-side, 200 MB per file)

Tool	What it does	Engine
Merge PDF	Combine multiple PDFs into one.	pdf-lib
Split PDF	Extract each page into its own PDF.	pdf-lib
Rotate PDF	Rotate all pages by 90°, 180°, or 270°.	pdf-lib
Images to PDF	JPG, PNG, or WebP images into a single PDF.	pdf-lib
MP4 to MP3	Extract audio from an MP4 video as MP3.	ffmpeg.wasm

The four PDF tools share one tab at /tools/pdf. Each tool page has a dropzone, a batch queue (one file at a time, live status per file), and a privacy banner. MP4→MP3 needs the COOP/COEP headers on /tools/* so ffmpeg.wasm can use SharedArrayBuffer.

Web tools (fetchers)

Tool	What it does
Loom Downloader	From any loom.com/share/ link: HD MP4 video, transcript as TXT, SRT, VTT, or JSON, and preview assets.
AI Chat Export	Paste a public share link from Claude, ChatGPT, DeepSeek, Qwen or Grok — the tool detects which chat it is and exports the conversation as Markdown, TXT, DOCX, or PDF.
Vercel Domain Checker	Check whether a *.vercel.app subdomain is available for your next deployment.

Machine interfaces

The card is not only a web page. proxy.ts (Next 16's middleware) routes by client:

You are	Try this
A browser	Open / for the tool hub; /whoami for the card; /about for the story.
curl / wget / httpie	curl -sS -A curl https://nicekit.vercel.app → your IP as text/plain.
A JSON client	curl -sS -H 'Accept: application/json' https://nicekit.vercel.app → JSON with ip, origin, weather, request. Speed, DNS, and VPN stay in the browser and are not in the JSON.
Reverse DNS	curl -sS https://nicekit.vercel.app/hostname → PTR name, or empty.
An agent	Read /llms.txt for the machine index.

One API route takes writes: POST /api/tools/stats — the anonymous conversion beacon. It returns 400 on bad JSON, 403 on a cross-origin Origin, and 429 past 30 requests per minute per IP. The web tools use their own routes under /api/loom/*, /api/chat/[provider] (and /api/chat/[provider]/export, which dispatches Claude, ChatGPT, DeepSeek, Qwen and Grok shares), and /api/vercel-domain.

Why it runs in the browser

• It would measure the wrong thing. A server-side speed test measures Vercel's network, not the visitor's. Same for the DNS probe: it must resolve from your device to report your resolver.
• Body-size cap. Vercel Hobby caps request bodies at 4.5 MB. PDF and video conversions would hit that limit server-side, so they run client-side and files never transit a server.
• Privacy. User files and derived facts stay in the tab.

The server side is deliberately small: /whoami is an async server component (loadVisitor → IP, origin, weather; recordPageVisit → counters), / is the tool hub, proxy.ts handles the CLI/JSON routing and Client Hints, plus /json, /hostname, and the tool fetcher routes. There is no BFF layer — it was sketched (/api/me) and deleted because it would duplicate loadVisitor without hiding the client-only probes.

Data and privacy

Nothing identifying about a visitor is stored. The only persisted state lives in Upstash Redis:

• visits:total — incremented on HTML loads of /whoami only (curl and /json don't count).
• visits:countries — which two-letter country codes have shown up.
• cache:origin:{ip} / cache:weather:{lat,lon} — 10-minute caches so repeat visits don't re-hit ipwho.is / Open-Meteo.
• tools:conversions — anonymous per-category count of successful conversions.
• ratelimit:tools-stats:{ip} — short-lived, auto-expiring rate-limit key for the stats beacon.

No analytics, no cookies, no accounts. If Redis is down, counters show a dash and the site still works.

Stack

Layer	Choice
Framework	Next.js 16 (App Router, proxy.ts) on Vercel
UI	React 19, Tailwind CSS v4, TypeScript, client + server components
3D	Three.js + @react-three/fiber (desktop earth backdrop)
Files	pdf-lib, @ffmpeg/ffmpeg (WASM)
Speed	@cloudflare/speedtest
Persistence	@upstash/redis over REST, every module marked server-only
Tests	Vitest

Run locally

Requires Node 20+.

npm install
npm run dev

Then:

curl -sS -A curl http://localhost:3000/
curl -sS -H 'Accept: application/json' http://localhost:3000/
curl -sS http://localhost:3000/hostname

npm test        # vitest run
npm run lint    # eslint
npm run build   # production build

Deploy

Import this repository into Vercel; leave the root directory as .. No environment variables are required — the only runtime secret is optional:

• KV_REST_API_URL + KV_REST_API_TOKEN (Upstash REST). Without them, visit counts and conversion tallies degrade to dashes; everything else works.

The production slug is nicekit.

Lookup sources

Origin and ISP: ipwho.is and RIPE Stat, with ipinfo and ipapi.is filling gaps. Weather: Open-Meteo. DNS resolver: ip-api EDNS. VPN/proxy flags: ipapi.is (heuristic). Speed test: Cloudflare speedtest (@cloudflare/speedtest against speed.cloudflare.com). The page names each source inline next to the fact it produces.

Why open source

This repo is a working instrument and a proving ground: modern Next.js, edge deployment, client-only measurement, WASM file processing, and honest privacy limits. Read /about for the full account of why it exists and what it exercises, or start with docs/architecture.md.