In Practice

Nyrvex

Lab guides that end in something running

In Practice is a series of hands-on books for the people who operate infrastructure rather than evaluate it. Every chapter closes with a lab that runs on your own machine — no cloud account, no spare server — and with the error messages you will actually meet, their causes and their fixes.

The gap these books address is not conceptual. Engineers understand what a tool does within an hour, then spend months learning what the defaults will cost them and what happens at three in the morning. That second part is what gets written down here.

Book One — available

Cover of Vault in Practice by Thomas Zachmann

Vault in Practice

A Hands-On Lab Guide to HashiCorp Vault and OpenBao

598 pages · 24 chapters · 24 labs · PDF and EPUB

Follow a fictional logistics company from passwords-in-Git to a production-shaped installation. Split an encryption key with Shamir and then lose it on purpose. Write policies that fail, and find out why in one command. Issue database credentials that did not exist until they were asked for. Break a Raft cluster's quorum, and put it back together.

Five chapters ask you to destroy your own setup, because nobody who has recovered a sealed cluster under pressure learned how from a reference manual. The book covers the Vault Associate exam objectives in full and ends with a practice exam.

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PDF and EPUB · free updates for every future edition

What is in the book


Book Two — in preparation

Enterprise AI Platform

GPU infrastructure, model serving and running an AI platform in-house

The platform underneath the models: GPUs under Kubernetes, inference servers, an AI gateway with identity and quotas, governance, observability and the cost per thousand requests. Written for platform engineers, not for data scientists.

A German edition is finished and available free of charge. The English edition for this series is in preparation.


The author

Thomas Zachmann has spent more than twenty years building systems, most recently Kubernetes platforms for organisations where security and auditability are the requirement rather than the aspiration: on-premises, on bare metal, in air-gapped networks and in European sovereign clouds. CKS, CKA, CKAD.

He works as an independent platform engineer from Hamburg, Germany — thomaszachmann.de.