Alexander Langer

Alexander Langer

Modelling for Mistakes

@alxlngr · Germany
Consultant at Red Rainbow IT Solutions



Alexander is a freelance consultant and entrepreneur. He calls himself a polyglot, full stack developer, and solutions architect.

He has 20 years of experience in software and web development, contributed to several open source projects, conducted research in complexity theory and algorithms, holds a Ph.D. in computer science from RWTH Aachen University, co-founded and worked as the CTO of a company offering managed health care solutions, and nowadays works as an independent consultant.


Modelling for Mistakes

In many domains, software supports processes carried out by humans in the physical world; examples include logistics, medical care, or manufacturing.

Humans, however, make mistakes or might intentionally deviate from specified workflows; or they might be forced to cope with bugs in the software or system outages. Similarly, physical sensors may malfunction or might be subject to broken or incomplete integration. In such environments, it is therefore natural that the application state begins to diverge from the "physical" state of the real world, and any errors quickly begin to accumulate over time.

In this talk, we present common patterns for when and why application state may begin to differ from physical state, and how making mistakes and errors first class citizens of the domain model helps us to implement corrective measures to eventually reach a consistent state again and avoiding them in the future.

The Premier Software Modelling & Design Conference

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Amsterdam, Jan 30 – Feb 2, 2018



More speakers to be announced


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