Gregor Hohpe

Gregor Hohpe

This site is maintained by Gregor Hohpe ("hoh-puh").



I am a technical director with the Office of the CTO ("OCTO") of Google Cloud where I combine my experience as Chief IT Architect at Allianz SE, as a software engineer, and as a consultant to advise enterprises on their cloud and enterprise architecture strategy. Naturally, the opinions expressed on this site are my personal ones, not those of my current or past employers.

I enjoy seeing the field of IT from different angles (consulting, software engineering, corporate IT) and collecting my thoughts in my ramblings. I like to tinkered with hardware, mostly based on AVR micro controllers and Raspberry Pi. I am also fairly active on Linkedin.

Interests [MORE]

I aim to make building distributed and integrated solutions less difficult and error-prone by collecting and documenting Integration Patterns from many client projects. It all started with a paper at the PLoP 2002 conference, which evolved into a successful book, published in 2003. By now (2018) more than 75,000 copies have been sold.

I also help large organizations transform their IT infrastructure and processes to reduce cost and complexity while increasing software delivery velocity. You can find the related book and information at

Short Bio

As technical director in Google Cloud's office of the CTO, Gregor maximizes the benefit customers derive from a cloud-based IT model by combining organizational, software delivery, and IT infrastructure transformation. Riding the "architect elevator" from the engine room to the penthouse, he connects corporate strategy with technical implementation by making complex topics engaging and approachable without compromising technical accuracy.

Before re-joining Google, Gregor held a position as Chief Architect at Allianz SE, one of world's largest insurance companies. Having established accelerated innovation and complexity and cost reduction as architecture goals, he oversaw a global data center consolidation and deployed the first on-premise cloud and software delivery platform.

Gregor is known as co-author of the seminal book "Enterprise Integration Patterns", which is widely cited as the reference vocabulary for asynchronous messaging solutions. His book "37 Things One Architect Knows About IT Transformation" tells stories from the trenches of IT transformation while his articles have been featured in "Best Software Writing" by Joel Spolsky and "97 Things Every Software Architect Should Know". He is an active member of the IEEE Software advisory board.

My Books

I enjoy writing because putting my thoughts into words forces me to clarify my thinking and allows me to share it with a wide audience.

Enterprise Integration Patterns

Enterprise Integration Patterns

Gregor Hohpe and Bobby Woolf
ISBN 0321200683

2003, Addison-Wesley

37 Things One Architect Knows

37 Things One Architect Knows

Gregor Hohpe

2016, Leanpub

Chapters and Contributions

Enterprise Solution Patterns using Microsoft .NET

Enterprise Solution Patterns using Microsoft .NET

David Trowbridge, Gregor Hohpe, James Newkirk, David Lavigne
ISBN 0735618399

2003, Microsoft Press

Integration Patterns

Integration Patterns

David Trowbridge, Ulrich Roxburgh, Gregor Hohpe, Dragos Manolescu, E.G. Nadhan
ISBN 073561850X

2004, Microsoft Press

The Best Software Writing

Joel Spolsky
ISBN 1590595009

2005, APress

97 Things

97 Things Every Software Architect Should Know

Edited by Richard Monson-Haefel
ISBN 059652269X

2009, O'Reilly

97 Things

97 Things Every Programmer Should Know

Edited by Kevlin Henney
ISBN 0596809484

2009, O'Reilly

SOA Expertenwissen

SOA Expertenwissen (in German)

Gernot Starke, Stefan Tilkov (Eds)
ISBN 3898644375

2007, dPunkt Verlag

Potenziale Entdecken

Potenziale Entdecken (in German)

Ralf Schneider, Robert Becker (Eds)
ISBN 3662488396

2015, Springer


Martin Fowler inspired me to state a bit about my financial and other interests.

I am a full-time employee at Google Asia Pacific and routinely advise customers on IT solutions. I do not earn a commission from product sales nor bill my services as member of the Office of the CTO. I also work as an independent consultant, mostly teaching workshops. I am good friends with the founders or main committers of almost all open source ESB players, so I tend to pull examples from their products without favoring a particular one.

I hold stocks in mutual funds plus many of the popular IT companies, but not nearly enough to believe that my statements have any influence on their stock price or my net worth. Most of my stock is still in Google, of which I never sold a share. I believe it is a great company that will do many more great things.

I do monetize my site through Amazon's affiliate program and Google Adsense, although it's just enough money for some beers. I occasionally request free review copies from publishers without any obligation to post a positive review. If I do find the book particularly noteworthy, I post a brief mention on the main page or a review on Amazon.

This Site

This site and it's design are about as old as EIP - over 15 years. The site is completely static, rendered by a mix of Ant 1.7 and XSLT, and now deployed to Amazon S3 and Cloudfront. I updated some of the HTML to be somewhat HTML 4.0 compliant, but a lot of it is still the way the Web was around 2002. Bless backwards compatibility!

Projects [MORE]

The domain of Enterprise Integration Patterns is much broader than asynchronous messaging. That's why I am trying to collect more Enterprise Integration Patterns, mostly focused on stateful interactions between systems. But it's slow going...

A long time ago, I created a number of tools to automate tedious EAI development, such as StubGen (a code generator for TIBCO AE) and TibDoc (a documentation generation tool). I have also created a messaging toolkit that demonstrates the patterns in my book. I am in the process of open-sourcing it.

» More very old Projects