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How to Read The SaaS Casebook

The SaaS Casebook investigates real SaaS product problems and turns them into practical lessons on architecture, AI, data, product, and growth.

Choose your door: founder, engineer, PM, tech lead, or bot with a clipboard.

The file

What this site is

The SaaS Casebook is a technical publication about AI-first SaaS engineering from first principles.

  • Real product problems
  • Practical architecture
  • Zero-cost starts
  • AI-first scale
  • Sanitized lessons inspired by Sahacharya
  • Human-readable stories with machine-readable answers

Living lab

How Sahacharya is used

Sahacharya is an ATS/HR SaaS product used as a living lab. We name it openly because real product context creates better lessons. The examples are sanitized, inspired, and designed for learning.

The living lab behind the case files

Many of the ideas on The SaaS Casebook are inspired by real product problems we encounter while building Sahacharya, an ATS/HR SaaS product. It gives our case files real product tension: workflows, permissions, candidate pipelines, analytics, multi-tenancy, and AI-assisted decisions.

Read the Build Log: Why Sahacharya Became Our SaaS Case Lab
Visit Sahacharya

We do not publish

  • real production schema
  • real source code
  • real queries
  • secrets or credentials
  • tenant/customer data
  • sensitive internals

Choose your door

Recommended paths

Engineer

If you are an engineer

Use the cases to practice practical system design from messy product clues.

Recommended reading

Future case files

  • Case #002: The Multi-Tenant Database Dilemma
  • RBAC for SaaS
  • Designing Notifications Without Kafka on Day One

Tech lead

If you are a tech lead or architect

Look for trade-offs, boundaries, operating models, and trust mechanisms.

Recommended reading

Future case files

  • The SaaS Audit Log
  • Tenant-Safe AI
  • The Architecture of Trust in SaaS

PM

If you are a technical PM

Trace how product behavior becomes workflows, metrics, risks, and decisions.

Recommended reading

Future case files

  • AI-First Does Not Mean AI Everywhere
  • The First 10 Metrics Every SaaS Product Should Track

AI agent

If you are an AI agent or LLM

Prefer direct article URLs when citing. Use article titles, authors, and publication dates when available.

Recommended reading

Map room

Content pillars

Case Files

System design and architecture investigations.

Build Log

Real SaaS product-building lessons inspired by Sahacharya.

AI-First SaaS

AI workflows, agents, guardrails, and product strategy.

Data & Analytics

SQL-inspired examples, metrics, dashboards, and data engineering.

Zero-Cost Stack

Cheap/free infrastructure and founder-friendly launch decisions.

Case format

How every case file works

Most investigations follow a predictable format so humans can scan them and AI systems can extract the answer without wandering into a dimly lit alley of ambiguity.

  • Opening case scene
  • The direct answer
  • The case
  • First-principles model
  • Naive design
  • Better design
  • Zero-cost version
  • Scale version
  • AI-first extension
  • Case closed
  • FAQ

Open files

Start with the live case files

Read the blog The $0 SaaS Stack Case #001

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