Case Study: Practical tools and strategies for tackling legacy practices and legacy systems in a fast-growing startup.
- 2. Â Case Study: Practical tools and strategies for tackling legacy practices and legacy systems in a fast-growing startup.
- 9. Goals for this talk Simon Brownâs C4 Model & Software Guidebook. DDDâs Strategic Design. Wardley Maps.
- 11. Based on True Life Events
- 12. Based on True Life Events pero contados por un argentino
- 14. Discovery What is the software architecture? What does the infrastructure look like? Which projects are in progress? How are projects managed ? How is work assigned and managed? What is the level of alignment?
- 15. The software guidebook C4 Model: Context, Containers, Components and Code
- 16. The software guidebook It focusses on the visual communication and documentation of software architecture. The core of this is the C4 software architecture model and the software guidebook.
- 18. Level 1: System Context diagram What are we building? Who is using it? (users, actors, roles, personas) How does it fit into the existing environment? (systems, services) https://c4model.com/#coreDiagrams
- 19. Level 2: Container diagram High-level shape of the software architecture, showcasing responsibilities distribution, major technology choices and containers communication. A container is a separately runnable/deployable unit that executes code or stores data. https://c4model.com/#coreDiagrams
- 20. Level 3: Component diagram Decomposition of each container identifying the major structural building blocks, called âcomponentsâ, and their interactions. Includes responsibilities and technology/ implementation details. https://c4model.com/#coreDiagrams
- 22. Level 4: Code UML class diagrams, entity relationship diagrams or similar. Optional level of detail available on- demand and automatically generated using tooling. https://c4model.com/#coreDiagrams
- 23. Discovery Phase 1 One-on-one meetings with the head of each dptm
- 24. ⊠⊠?
- 25. My goals What is the software architecture? What does the infrastructure look like? Which projects are in progress? How are projects managed ? How is work assigned and managed? What is the level of alignment?
- 26. Discovery Report There are 19 âthingsâ (systems?, projects?, modules? components? features?). Each âthingâ has a very clear user/role. There is no portfolio. There is no team. There is no alignment.
- 28. Infrastructure
- 32. Discovery Phase 2 Software Development Practices
- 35. Domain Driven Design IMHO DDD is one of the most essential concepts in software development.
- 36. DDD Strategic Design Context Maps Core Domain Supporting Subdomain Generic Subdomain Bounded Context Relationships Solution SpaceProblem Space
- 37. BC Relationships: Big Ball of Mud Shared Kernel Customer/Supplier Published Language Open Host Service Anticorruption Layer Conformist Separate Ways
- 44. BBOM
- 49. Organizations which design systems are constrained to produce designs which are copies of the communication structures of these organizations. Melvin Conway - How Do Committees Invent? (1968)
- 51. Guiding Principles Common Closure Principle and Single Responsibility Principle. The Acyclic Dependencies Principle: Allow no cycles in the component dependency graph. The Stable Dependencies Principle: Depend in the direction of stability.
- 52. âThe best bits of DDD happen outside your IDEâ Nick Tune - Patterns, Principles, and Practices of Domain-Driven Design
- 53. Wardley Maps
- 54. Wardley Maps A Wardley Map is a representation of the landscape in which a business operates. A Wardley Map represents the shared assumptions being made about a context and hints at what strategic options are available.
- 55. Wardley Maps The cycle The Landscape Climatic Patterns Anticipate (by applying climatic patterns) Doctrine Context Specific Play Gameplay Loop
- 56. Crossing the river by feeling the stones. By Simon Wardley
- 59. Crossing the river by feeling the stones. By Simon Wardley
- 60. Crossing the river by feeling the stones. By Simon Wardley
- 61. Crossing the river by feeling the stones. By Simon Wardley
- 62. Evolutionary Characteristics Stage of Evolution I II III IV Genesis Custom Product (+rental) Commodity (+utility) Ubiquity Rare Slowly increasing consumption Rapidly increasing consumption Widespread and stabilising Certainty Poorly understood Rapid increases in learning Rapid increases in use / fit for purpose Commonly understood (in terms of use) Market Undefined market Forming market Growing market Mature market User perception Different / confusing / exciting / surprising Leading edge / emerging Common / disappointed if not used or available Standard / expected Failure High / tolerated / assumed Moderate / unsurprising but disappointed Not tolerated, focus on constant improvement Operational efficiency and surprised by failureKnowledge management Uncertain Learning on use Learning on operation Known / accepted Practices Novel Emerging Good Best
- 63. Crossing the river by feeling the stones. By Simon Wardley
- 64. Crossing the river by feeling the stones. By Simon Wardley
- 65. Crossing the river by feeling the stones. By Simon Wardley
- 66. Crossing the river by feeling the stones. By Simon Wardley
- 67. Crossing the river by feeling the stones. By Simon Wardley
- 68. Crossing the river by feeling the stones. By Simon Wardley
- 69. C D E B A
- 75. Mapping Maturity by Chris McDermott
- 76. Mapping Maturity by Chris McDermott
- 77. Mapping Maturity by Chris McDermott
- 78. Discovery Phase 2 Software Development Practices
- 80. Main Issues A very loose criteria of what a "version" is. Huge differences between development environments, each developer has their own criteria and tools. Limited availability of environments. Developers are not involved in the release process. Creating and deploying a new version is a manual process and takes a couple of days. Monthly deployment cadence.
- 81. DevOps: Bottleneck Analysis Constraints Evolve in a predictable way
- 82. Constraints Evolve in a predictable way Inconsistent Environments - Environment Creation Manual Intervention - Code deployment Poor SDLC practices - Test setup and run rate Overly tight architecture Product Owners
- 83. Principles & Practices The Twelve-Factor App Developers who wrote code are closely involved in deploying it and watching its behaviour in production. Continuous Integration Visibility. Invest early in monitoring Coding the Architecture & Infrastructure as Code.
- 84. Principles & Practices âThere is a SaaS for thatâ or âThere is an API for thatâ Donât build it in-house. Leverage existing APIs. Focus only on whatâs core for the product, donât reinvent the wheel. Optimize for speed of development. Remove all impediments to a faster development cycle.
- 85. Key Changes Unification of the development environment (Macs, PHPStorm and Vagrant for everyone) Implemented 8 of the 12 points in the The Twelve-Factor App. Introduction of git and the gitflow branching strategy. Versioning Introduction of jenkins and CI Reduced time to release from days to seconds. Reduced deploy cadence from a monthly to daily. Moved from Pet to Cattle servers. Decided to start developing services with Java and Docker.
- 86. I. Codebase (One codebase tracked in revision control, many deploys) II. Dependencies (Explicitly declare and isolate dependencies) III. Config (Store config in the environment) IV. Backing Services (Treat backing services as attached resources) V. Build, release, run (Strictly separate build and run stages) VI. Processes (Execute the app as one or more stateless processes) VII. Port binding (Export services via port binding) VIII. Concurrency (Scale out via the process model) IX. Disposability (Maximize robustness with fast startup and graceful shutdown) X. Dev/prod parity (Keep development, staging, and production as similar as possible) XI. Logs (Treat logs as event streams) #291 XII. Admin processes (Run admin/management tasks as one-off processes)
- 90. Feedback Door 5 - WOW! I learned something new and useful (in a fun way). 4 - ⊠3 - ⊠2 - ⊠1 - I wish I would have been watching Netflix.