Published

Session: Event Sourcing Applicative Profunctors - Jeremy Chassaing Event Sourcing in function programming decide pure function, immutable objects evolve takes 1 event applies it to the state Link it together -– initial state -– now we have Event Sourcing command: only what is needed to ‘decide’ event: only what is needed to ’evolve' cf Aggregate Take any aggregate, and it has enough information to run, without needing external data -we can rewrite any aggregate to this -without needing external data...

Model: Design Heuristics Model: 3 kinds of heuristics guide you closer to the solution design pattern DDD pattern structure for event source records api design approach guide you to other heuristics determine our beliefs or values eg. DDD guiding heuristics compose based on subdomains ubiquitous language domain events Competing Heuristics Do you do TDD? Kind of why? depends on complexity of the problem Heuristic: Don’t checkin (a large chunk of) code without tests ; before or after does not matter...

Lightning Talk: Dearth of a Drafter - Einar Høst Too many crafters talk: death of a craftsman what is the craft? who is the crafter? multiple crafts we only focus on ‘code craft’ not enough drafters too much focus on code Drafter: -good at externalising mental models -collaborative modelling -multidisciplinary Paper: computer as models drafter: catalyst for communication writing software is easy to keep writing software is hard...

Lightning Talk: No, you don’t need to access my data. - Alberto Brandolini Article -– information in another bounded context “liquidity is another concern” -– coupling due date != date the money is expected -eg customer bankrupcy not the same Policies to the rescue -– Recap 1 2 3

Lightning Talk: People and Patterns - Andrew Harmel-Law Patterns Book: A Pattern Language Book: Design Patterns Book less known -MVC -layers Patterns Community “a system of patterns” -patterns do not exist in isolation Book: Patterns of Enterprise Architecture layers Book: brokers, types, filters “system aspect starts to fade” -– Book: release it new trend: patterns include deployment -– Book_ Team Topologies - Matthew Skelton & Manuel Pais...

Lightning Talk: Reductionism and Holism in DDD - Trond Hjorteland “DDD is limited because it’s too structured” -- Coplien We fight complexity by enforcing structure We’re stuck in the analytic mindset We use reductionism -split it up -explain the parts -to explain the whole what makes sand soft we simplify complex -> constrained to make it complicated “loses essential properties when taken apart” analysis is not enough...

Lightning Talk: Tech alignment with Narratives - Lothar Schulz quote What are narratives? text documents problem statement - needs to be really clear - 5-6 sentences max - focus on why context / background - readers from different solution approaches - 3 options max link back to the why RACI -Responsible -Accountable -Consented -Informed Why use narratives exercise: Ham&Eggs

Lightning Talk: The businesscase for architecture - Niek Van Raaij arch, devops, secutiry Level 1: too vague hard business case vague -– Level 2: missing why what would we do with that 10% now free? still have to pay “and fire 10% of developers” would be a business case -– How to do write better business cases “reduce rollback time by 10%” how much is the lost revenue of a 10 minute downtime?...