I replaced a $120/year micro-SaaS in 20 minutes with LLM-generated code

2026-01-29 · Source: The Pragmatic Engineer · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Software Development & Engineering, Entrepreneurship & Start-ups · Depth: Intermediate, medium

Summary

The author, initially skeptical of claims that Large Language Models (LLMs) would disrupt Software-as-a-Service (SaaS), recounts a first-hand experience replacing a micro-SaaS costing $120/year with LLM-generated code. The service, Shoutout.io, collected and rendered testimonials for the author's website. Frustrated by broken billing and unhelpful customer support, the author rebuilt the core functionality—displaying existing testimonials, adding new ones via JSON, and ensuring good visual presentation—in just 20 minutes using Codex. This involved asking Codex for a plan, refining it for a modular compile-time build step, adding the build step locally and on Netlify, testing, tweaking UX, generating a schema, and deploying. The result visually matched the original, eliminating the third-party dependency.

Key takeaway

For software engineers evaluating micro-SaaS dependencies that offer minimal ongoing value, consider using LLMs to rebuild specific use cases. Your comfort with command-line tools and verifying code output makes this a rapid and potentially enjoyable process, eliminating recurring costs and external dependencies, especially when a vendor's product quality or support declines.

Key insights

LLMs significantly reduce the time and cost for developers to replace simple, static SaaS functionalities.

Principles

• SaaS providing static value is vulnerable to LLM replacement.
• Ongoing value and compliance differentiate robust SaaS.

Method

To replace a simple SaaS, use an LLM to generate a modular, compile-time build step for static content, storing data in JSON and deploying via a service like Netlify.

In practice

• Replace static content SaaS with LLM-generated code.
• Store dynamic data in JSON for easy LLM integration.

Topics

• LLM Code Generation
• Micro-SaaS Replacement
• Developer Productivity
• Custom Software Development
• SaaS Business Models

Best for: Software Engineer, AI Engineer, Entrepreneur

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Editorial summary, takeaway, and curation by AIssential. Original article published by The Pragmatic Engineer.