Geecon 2016 – Day 1 – Day 2

Day 1

A Decade of DDD, CQRS, Event Sourcing by Greg Young

• One of the Fathers of CQRS methodology
• Heavily involved in DDD
• Event store database
• Key takeaway - don't be a fundamentalist in any technology/design pattern etc.

Caught in the Act: Kotlin Bytecode Generation and Runtime Performance by Dmitry Jemerov

• Kotlin - Open Source, backed by JetBrains
• null-safe
• Compiled to Java bytecode -- fully interoperable
• Lots of benchmarks in the presentation, showing comparisons to Java

Rise of the Machines - Automate Your Development by Sven Peters

• Automate everything :)
• Comparison between screenshots as a git hook

Lessons learnt on production by Greg Young

• A sobering talk
• Limit abstractions
• Cascading problems
• Randomized tests
• Make bug reporting and debugging a part of your design
• Property-based tests

Day 2

Greenfield effect: Patterns for Effective Disaster Delivery by Julian Warszawski

• More like a standup than presentation :)
• Greenfield is not always easier than Brownfield

Navigating ALL the Knowledge by James Weaver

• Graph DB application
• Far from perfect UI, but a good idea
• Concept Map

How shit works: Storage by Tomer Gabel

• If you want high performance, you're not fully abstracted from HDD/SSD
• There's a lot to know about SSDs
• 'Shit' in title boosts attendance

Confidence in the frontend with Elm by Ossi Hanhinen

• Compile time errors
• Functional patterns
• Component-like frontend
• Elm language

What's Oracle Doing With JavaScript?! by Geertjan Wielenga

• Oracle JET
• Not a framework -- set of tools

Day 3

Twelve BDD Antipatterns - stories from the trenches about how NOT to do BDD by John Smart

• BDD is not a tool for writing tests
• BDD is a communication tool
• Don't get technical
• Be descriptive

Need Robust Software? Make It Fragile by Yegor Bugayenko

• Fail-fast instead of Fail-safe
• Assume clients fault when your method gets bad data

Testing Patience by Michael Feathers

• Testing is a way of thinking harder about what you write
• Don't focus on test running tools
• Tests help even not executed :)

What we can learn from Smalltalk by Kirk Pepperdine

• OO comes from Smalltalk
• A lot of Java concepts come from Smalltalk
• Smalltalk

Top 10 Performance Mistakes by Martin Thompson

• Data centers use as much energy as the airline industry
• We write software that mostly parses strings and logs stuff
• Measure everything
• Make benchmarks a part of your code
• Profile your code for fun :)