Preface

The Architect's Field Guide on the desk

I wrote this book because I kept seeing the same failure. A team splits a working system into services, calls the result modern, and then spends the next two years paying for a distributed monolith: lock-step deploys, a shared database, and a request path that dies because every hop can time out.

The question that actually matters is not “how many services.” It is whether a boundary earns the cost of being remote. That is the spine of the book.

Adaptive Granularity Governance (the Khan Microservice Pattern) is how I make that question answerable. The RVx Index is the score. I spent 2024 and 2025 on the research because the concepts in this book were still theoretical: the field had no proven formula that named a distributed monolith. That work is the Fulcrum paper and the research site. Chapter 11 is the only place in this book the formula, the defaults, and the evidence tiers are written down. I am not reprinting the equation here. If an old slide has the exponents swapped, throw the slide away.

Read a score as a warning light, not a trophy:

  • Above 0.7 - healthy on the declared profile. Still show the three components.
  • 0.4 to 0.7 - at risk. Find the weak signal before you split or merge.
  • Below 0.4 - the boundary is not earning its keep.

The whole book is here. Twenty-three chapters. There is no later paid half, and there is no ten-chapter teaser. Parts I–III are the substrate: organization, data, evidence. Chapter 11 is the measurement. Parts V–IX are isolation, platform, agents, migration, and maturity. Part X is cost, validity, and Goodhart.

I work on AWS. The examples lean that way. The arguments are not AWS-specific.

If you use the method, cite it. Formats are in CITATIONS.md. ORCID: 0009-0008-3592-4162.

Viquar Khan
September 6, 2026

Copyright © 2019–2026 by Viquar Khan.

Original methods, please cite:

  • Adaptive Granularity Governance: The Khan Microservice Pattern
  • Service Decomposition Workflow
  • Microservices Maturity Assessment (KM3)

First edition: January 2019. Second edition: January 2026. Version 2.1: September 2026.

DOI: https://doi.org/10.5281/zenodo.22654421 Repository: https://github.com/vaquarkhan/microservices-recipes-a-free-gitbook

See CITATIONS.md, LICENSING.md, and DISCLAIMER.md.