Legacy Code, OOP vs Functional Programming & MORE | Michael Feathers In The Engineering Room Ep. 10

When Michael Feathers talks it’s usually worth listening. Michael is thoughtful about software and software design, for example Michael is the person who invented the term SOLID as an approach to software design. Michael is also the author of a book that is on the “must read” list of nearly every real-world programmer “Working with Legacy Code”. In this chat, Michael Feathers describes this book as "scare tactics for TDD" - When you know how hard it is to write tests for existing code, you’ll write tests from the beginning! Michael and Dave talk broadly about automated testing, software architecture and design principles for quality code, and Michael claims that “OO, when it's done right, looks a lot like FP”. The "Engineering Room” is a monthly series of long-form talks, with influential people from the world of software, published on the Continuous Delivery channel each month and hosted by Dave Farley. ___________________________________________________ 🙏The Engineering Room series is SPONSORED BY EQUAL EXPERTS Equal Experts is a product software development consultancy with a network of over 1,000 experienced technology consultants globally. They increase the pace of innovation by using modern software engineering practices that embrace Continuous Delivery, Security, and Operability from the outset ➡️ https://bit.ly/3ASy8n0 ------------------------------------------------------------------------------------- Also from Dave: 🎓 CD TRAINING COURSES If you want to learn Continuous Delivery and DevOps skills, check out Dave Farley's courses ➡️ https://bit.ly/DFTraining 📧 Get a FREE guide "How to Organise Software Teams" by Dave Farley when you join our CD MAIL LIST 📧 The best way to keep in touch with the latest discussions, events and new training courses, get FREE guides and exclusive offers. ➡️ https://www.subscribepage.com/organise-teams-guide ------------------------------------------------------------------------------------- 🔗LINKS: Millers Law ➡️ https://en.wikipedia.org/wiki/Miller's_law +7 -2 ➡️ https://en.wikipedia.org/wiki/The_Magical_Number_Seven,_Plus_or_Minus_Two Ian Cooper ➡️ https://youtu.be/EZ05e7EMOLM Martin Thompson (TER Episode) ➡️ https://youtu.be/sIBrFuzR3cs Simon Brown C4 Architecture ➡️ https://c4model.com Michael Feathers’ twitter ➡️ @mfeathers Link to Michael’s talk: “The Deep Synergy between testability and good design" ➡️ https://youtu.be/4cVZvoFGJTU LMAX Disruptor ➡️ https://lmax-exchange.github.io/disruptor/ ------------------------------------------------------------------------------------- 📚 BOOKS: 📖 Dave’s NEW BOOK "Modern Software Engineering" is now available here ➡️ https://amzn.to/3DwdwT3 📖 "Continuous Delivery Pipelines" by Dave Farley paperback ➡️ https://amzn.to/3gIULlA ebook version ➡️ https://leanpub.com/cd-pipelines 📖 The award-winning "Continuous Delivery" book by Dave Farley and Jez Humble ➡️ https://amzn.to/2WxRYmx 📖 Working Effectively with Legacy Code, Michael Feathers ➡️ https://amzn.to/3hP0F4z 📖 Growing Object Oriented Software Guided by Tests, By Nat Price & Steve Freeman ➡️ https://amzn.to/2Lt3jho 📖 Team Topologies - Matthew Skelton & Manuel Pais ➡️ https://amzn.to/2Y0NdSO 📖 Extreme Programming Explained: Embrace Change, Kent Beck ➡️ https://amzn.to/2GpQRjE NOTE: If you click on one of the Amazon Affiliate links and buy the book, Continuous Delivery Ltd. will get a small fee for the recommendation with NO increase in cost to you. __________________________________________________ CHAPTERS 00:00 Welcome 00:40 Introducing Michael Feathers 02:26 Good Design in Code is an Artefact of the Way Our Minds Work 05:21 “Every Time you Encounter a Testability Problem, there’s an Underlying Design Problem” 07:45 A Test is a Program to Understand a Program 10:00 Painful Tests Teach you About Good Design 12:50 The One-More-Thing Problem 13:38 Test First is Coding at a Distance 18:45 Techniques to Tackle Difficult Parts of TDD 20:20 Glue System? Or Computational System? 21:30 Test Coverage is NOT the Goal 22:28 “OO when its done right looks a lot like FP” 27:30 Modularity, Unit Tests and Separation of Concerns 32:39 Quality Views and Key Responsibilities 38:00 Can you Explain Your System in 4 or 5 Objects? 40:50 CRC-Thinking and Cohesion 42:00 Cognitive Load, Microservices and Coupling 46:20 Platforms and Team Topologies 48:08 Scale is the Enemy 52:00 Engineering at Different Scales 54:40 Economics and Buy v Build Choices 58:20 Complex Systems - Physics Bound or People Bound? 1:01:00 Determinism and Concurrency 1:04:00 LMAX and Incremental Design 1:07:30 Constraints and Globals 1:10:40 Moving the Blue Frog 1:12:45 Dynamics of Software Systems and Social Systems 1:14:00 Wrap Up