Preface

What is this book?

This book is a guide about:

• Software delivery: how to run & maintain software in production?

• DevOps: a methodology to make software delivery more efficient

Instead of focus on culture & theory, this book focuses on hand-ons guide:

• Step-by-step examples about how to run real system & real code.
• Core concepts & best practices of modern DevOps and software delivery.

Why this book exists?

• There is no hands-on guide that teach software delivery end-to-end.

• Software delivery is current learned in the hard way - through trial and error - which can be very costly (outages, data lose, security breaches…)

[!NOTE] The author learned from his experience when he worked at LinkedIn in 2011:

• LinkedIn’d just IPO, share price was up 100%, revenue was growing 100% by year, 100M members, growing fast.
• From the inside, the company was in turmoil because of software delivery - a $10 billion company could not deploy code:
  • They deployed once every 2 weeks through a painful, tedious, slow, error-prone way
  • A deployment went so bad, that it could not be completed; new changes, some fixes, more issues…Team worked overnight several days, then everything was roll-backed.
• They kicked of Project Inversion:
  • new features development was freezed for several months
  • the entire engineering, product, design team reworked all the infrastructure, tooling, technique
• Months later, they could deploy dozens of times per day:
  • with fewer issues, outages
  • allowing the whole company move much faster

[!NOTE] How did they do that?

• They didn’t know what they didn’t know

• They learn about best practices from the industry:

  • Trunk-based development (from one company)
  • Canary deployment (from another)
  • Feature toggles (from another)
  • …

• Most developers don’t know what they don’t know:

  • About software delivery and DevOps
  • Best practices that top tech companies had figured out

• This book helps you learn from the experience of others so you can build software faster, more reliably and more securely.

[!WARNING] The results from adopting DevOps can be wonderful, but the experience along the way may be not.

Watch out for snakes

• “DevOps” is used to describe a lot of unrelated concepts. ⛓️‍💥🌕🌑

  e.g. A TLS certificate (& the cryptography behind it), a deployment pipeline, and backing up data from a database.

[!NOTE] What makes DevOps hard? (It’s not the complexity of the concepts)

• It’s the number of concepts to master (DevOps is an incredibly broad surface area)
• It’s how to get everything connected together correctly (or nothing works at all)

• “DevOps” is a box of cables. 🧰⛓️

  You pull out a cable but end up with a giant mess where everything is tangled together

[!TIP] This book try to untangle this mess of cables:

• Each cable in that mess is in fact a separate cable.
• In isolation, each concept in DevOps (a cable in that mess) is within your grasp.

• Sometimes, DevOps even feels like a box of snakes. 🧰🐍🐍

  You pull of a cable but end up getting bitten.

[!CAUTION] DevOps is current a giant mess:

• A new industry
• Tools, techniques aren’t mature
• It often feels like everything is broken, frustrating & hopelessly tangled

• In DevOps, each time you learn a new buzzword (a new concept):

  • it comes with 10 more unfamiliar buzzwords (it’s a mess of cables)
  • or it might try to by you (a cable or a snake)

  but stick with it & watch for the snake

Who should read this book?

Anyone responsible for deploying & managing apps in production:

• Individual contributors in operations roles: SREs, DevOps Engineers, SysAdmins…, who wants to level up about software delivery & DevOps.

• Individual contributors in development roles: Software Engineers/Developers.., who wants to learn about the operations side.

• Managers: Engineering Managers, CTOs…, who want to adopt DevOps & software delivery best practices in their organizations.

What is in this book?

What isn’t in this book?

Code examples

• This book includes many examples to work through, which is available at GitHub repository: https://github.com/brikis98/devops-book

• The code samples are organized

  • by chapter (e.g. ch1, ch2),
    • and within each chapter, by tool (e.g. ansible, kubernetes, tofu)

[!TIP] The examples show what the code looks like at the end of a chapter.

To maximum the the learning:

• write the code yourself
• check the “official” solutions at the end

Opinionated Code Examples

The code examples represents just one opinionated way to implement this book core concepts - IaC, CI/CD…

[!IMPORTANT] In real world, there is no single “best” way that applies to all situations:

• All technology choices has a trade-off.
• Some solution maybe a better fit in some situations that others.

Always use your judgment to pick the right tool for the job.

[!NOTE] The core concepts in this book only change & evolve over a long time span (5-10 years). But the code examples that implement these core concepts may change more frequently. e.g. Kubernetes has a release cycle of 4-month¹.

You Have to Get Your Hands Dirty

This book will teach you principles, techniques, tools about DevOps & software delivery.

But you can only achieve serious results if you learn by doing:

• re-create the example code yourself

  • writing code
  • running code
  • make the code work

• do the extra get your hands dirty section & tweak the examples

  • customize to your needs
  • break things
  • figure out how to fix them
  • …

Using Code Examples

The code examples in this book may be used

• in your programs and documentation (but not too much)
• but not for selling & distribution