Start Learning
Javaneer
Back to roadmap
🌱
Stage 6

Evolutionary Architecture

Architecture is a verb: guide it, don't freeze it.

Architecture is never finished - it evolves, and the senior skill is guiding that change deliberately instead of letting it rot. Fitness functions that automate architectural guardrails, coupling and cohesion as the metrics that decide how changeable a system is, technical debt as a managed tool, the strangler-fig pattern for replacing legacy incrementally, and architecture decision records so the system remembers why.

6 Lessons in this stage1 h 24 min
Start the first lesson

Lessons in this stage

  1. 01

    Architecture Is a Verb

    Intermediate

    Why no architecture is final: requirements, scale, and teams change, so the goal is a system that's cheap to change - and the 'ilities' (the architectural characteristics) you're really designing for.

    13 min
  2. 02

    Fitness Functions

    Advanced

    Automated tests for architectural characteristics: an ArchUnit rule guarding a dependency boundary, a performance budget, a coverage gate - so the qualities you care about can't silently erode.

    15 min
  3. 03

    Coupling & Cohesion

    Advanced

    The two metrics under every architecture decision: high cohesion within a component, low coupling between them - what afferent/efferent coupling and connascence tell you about changeability.

    15 min
  4. 04

    Managing Technical Debt

    Intermediate

    Debt as a deliberate tool, not just sloppiness: the debt quadrant (prudent/reckless × deliberate/inadvertent), making debt visible, and paying it down without a doomed big rewrite.

    14 min
  5. 05

    The Strangler Fig

    Advanced

    The pattern for replacing a legacy system incrementally: route new behavior to the new code, migrate slice by slice behind a facade, and retire the old - how you'd finally replace ledger-legacy.

    15 min
  6. 06

    Architecture Decision Records

    Intermediate

    Give the architecture a memory: a lightweight ADR captures a decision, its context, and its consequences - so future engineers evolve the system knowing why it is the way it is.

    12 min