Real AI agent use cases, with sources and setup prompts

Replace expensive SaaS with a custom internal tool

Built the MVP of a project management system in two all-nighters with Claude Code; it now runs a 110+ person business and three devs own it.

Free to start1-3 daysAdvancedSource linked

Source

@Oasiszn on X · 2026-08-11

Written in our own words. Credit to the original author. Link checked 2026-10-14.

What they did

Built the MVP of a project management system in two all-nighters with Claude Code; it now runs a 110+ person business and three devs own it.

Result (as claimed)

Claims it removed over $50k in SaaS expenses.

Tools they used

Claude Code

Tools in our setup

Suggested in the setup steps below; not named in the source.

LovableSupabaseResendStripeGitHubVercel

Cost: Lovable free plan, Supabase Free, Stripe has no monthly fee (2.9% + 30¢ per transaction), Vercel Hobby, GitHub Free, Resend Free. Expect Supabase Pro $25/mo and Vercel Pro $20/mo at launch.

Set it up

  1. Spec the MVP

    Turn my idea into a one-page MVP spec: user, problem, the 3 core screens, data model (tables and columns), and what is out of scope. Ask clarifying questions first.

  2. Generate the app with Supabase

    Build this app with Supabase for auth and data. Create the tables from the spec, enable Row Level Security on every table with policies so users only see their own rows, and add email sign-in.

    Docs: docs.lovable.dev/integrations/supabase, supabase.com/docs/guides/database/postgres/row-l

  3. Add Stripe subscriptions

    Add a Pricing page and Stripe Checkout for a monthly plan. Use STRIPE_SECRET_KEY and STRIPE_WEBHOOK_SECRET from env, handle checkout.session.completed and customer.subscription.deleted webhooks to update a subscriptions table, and gate premium features on it. Test in Stripe test mode.

    Docs: docs.stripe.com/checkout/quickstart, docs.stripe.com/webhooks

  4. Send transactional email

    Send a welcome email on sign-up and a receipt after payment with Resend using RESEND_API_KEY and a verified domain.

    Docs: resend.com/docs/send-with-nodejs

  5. Deploy

    Push to GitHub and deploy on Vercel. List every env var I must add in Vercel Project Settings, then connect my custom domain.

    Docs: vercel.com/docs/environment-variables, vercel.com/docs/domains

  6. Launch checklist

    Review the app for launch: RLS on all tables, no secrets in client code, error pages, a privacy page and terms, and Stripe live mode switch steps.

Copy the full setup prompt

Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.

You are helping me set up this AI use case end to end in Claude Code.

Goal: Replace expensive SaaS with a custom internal tool
What the original author did: Built the MVP of a project management system in two all-nighters with Claude Code; it now runs a 110+ person business and three devs own it.
Reported result (as claimed by the author): Claims it removed over $50k in SaaS expenses.
Source: https://x.com/Oasiszn/status/2087209720239059375
Tools they used: Claude Code
Category: Vibe coding & apps

Please:
1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like).
2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure.
3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data.
4. Finish with a checklist to run it again next time.

Related use cases