Build a multi-tenant SaaS with an agent

The poster built a production multi-tenant SaaS in 15 days with Replit Agent, but hit issues like RLS bypasses and production pointing at the dev database, so checking its work was essential.

What They Did

The poster used only Replit Agent plus Architect to build a production multi-tenant SaaS over 15 days. Their workflow was spec-driven: write a spec, turn it into markdown, have Replit review it and propose a plan, sanity-check that plan with Perplexity or Codex, then let the agent work through a checklist while they repeatedly verified behavior and corrected issues like security, env vars, migrations, and deployment config.

How It Went

They got the SaaS built, but said the speed was misleading because every layer broke in unexpected ways, including RLS bypasses, double-encrypted OAuth tokens, reverted environment variables, and production pointing at the dev database. Even after finishing, they were still dealing with integrations, and migrations still struggled with triggers and security-definer functions.

Worth Knowing

The main catch was supervision overhead: the poster says the real work was constant verification, and also notes the agent could not read production logs, which made debugging harder.