I built a serverless URL shortener for $4.68/year (total)

I wanted two things: short links under my own brand (every link I share points traffic back to my site ), and a real excuse to run a complete system on the edge — DNS, distributed compute, storage, auth and a dashboard — in production, at zero infrastructure cost. The result is flino.link : a shortener that responds in under 10 ms from 300+ locations, runs entirely on Cloudflare's free tier, and whose only expense is the domain: $4.68 a year. This post covers the design decisions, which is where the interesting parts are. The architecture in 30 seconds A single Cloudflare Worker serves the whole domain: GET /<slug> — the hot path. One read from Workers KV (globally replicated) and a 302 redirect. Nothing else touches that path. /api/links — a REST API with Bearer auth to create, list and delete links. /admin — a single-page dashboard served as inline HTML from the Worker itself. No framework, no build step. A Durable Object with embedded SQLite keeps per-slug click counts. No servers, no containers, no database to manage. The whole Worker is three TypeScript files and zero runtime dependencies. Why a dedicated domain? My first idea was to hang the shortener off a route on flino.dev . Bad idea: shorteners attract abuse — spam, phishing — and their domains sooner or later end up on blocklists. If that happens, I don't want it dragging my main domain down with it. A separate domain isolates that reputation risk completely, and a short .link costs less than a coffee per year. KV for links, a Durable Object for counters This is the central design decision. Workers KV is perfect for a shortener's access pattern — read-heavy, write-light, reads served from the edge — but its writes are eventually consistent : two concurrent increments in different datacenters would clobber each other. For counting clicks, it's useless. A Durable Object solves exactly that: it's a single global instance with transactional SQLite storage. Every increment, no matter which datacenter it comes