Fractional.tools tech stack
The tools I lean on first—Supabase for data, Fly for the API, Inngest for jobs, Postmark for product email—with links to playbook reviews.
2 min read
Background
Fractional.tools is a small integration test bed—not a platform pitch. These are the core tools I wired in first because they cover data, API hosting, background work, and product email without turning the repo into a mail-ops or CRON shop. Full scored reviews live in the playbook; this page is the short map from the build-in-public hub.
Supabase
Why it’s here: Postgres, auth, and row-level security in one stack—the default backend for a vibe-coded micro-SaaS. Fractional.tools stores clients, rates, and calendar-linked billing data here instead of inventing a database layer.
Playbook: Supabase review → (full score coming soon)
Fly.io
Why it’s here: The calendar API—OAuth, webhooks, and everything that talks to Google and Outlook—runs on Fly edge servers. Docker config lives in the repo, hobby tier covers staging, and prod stays lightweight without AWS theater. React on Cloudflare serves the UI; Fly holds the backend that has to stay close to customers and scale per region.
Playbook: Fly.io review → (live scored review)
Inngest
Why it’s here: Calendar webhooks, signup tasks, Postmark sends, and Stripe hooks all fan out as jobs with retries and a UI the product team can see. When ten beta users broke our Google Calendar sync, orchestration—not more API workers—fixed it.
Playbook: Inngest review → (live scored review)
Postmark
Why it’s here: Transactional email that stays out of the spam folder—password resets, invoices, alerts—triggered through Inngest, not bolted onto a newsletter tool. Deliverability and suppression are someone else’s job.
Playbook: Postmark review → (live scored review) · peer: Resend
More stack pieces (Cloudflare, Sentry, MCP workbench, and the rest) will land here as playbook entries ship. See Stephan’s MCP workbench for what’s wired in .cursor/mcp.json today. For a dated story on calendar + Inngest, see Five users worked. Ten broke us.. For the full Fly write-up—including how the API sits next to Cloudflare and Supabase—see the Fly.io playbook entry.