Introducing Bounded Contexts After Domain Entanglement

87-column Order model split into 4 focused contexts. 40% faster features, 35% fewer bugs.

[Overview] System overview

One Order model served ecommerce, wholesale, marketplace, and subscriptions. 87 columns. 23 state transitions. Changes affected everything.

Domain separation created focused models for each context.

[Context] Situation before

Giant Order model. Every change required understanding all business lines. Bugs cascaded across contexts.

[Diagnosis] The real problem

Different business models have different concepts named the same. Ecommerce Order ≠ Wholesale Contract ≠ Marketplace Transaction.

Understanding the root cause changed everything.

[Boundaries] Working constraints

MIGRATION

  • Cannot migrate all at once
  • Existing integrations must continue working

Constraints are features, not obstacles. They guide design decisions.

[Decisions] Key tradeoffs

REJECTED

Keep shared model

Add complexity gradually

Each business line slows all others.

CHOSEN

Bounded contexts

Separate models per domain

Independent evolution. Clear ownership.

[Design] Architecture design

Ecommerce: Order (25 columns). Wholesale: Contract (20 columns). Marketplace: Transaction (22 columns). Subscription: Membership (18 columns). Shared kernel for common concepts.

From Shared Model to Bounded Contexts

87-column Order model split into focused contexts

Alt text

[Approach] Execution model

##### 12-Month Migration

Months 1-3: Define boundaries. Months 4-6: New features in contexts. Months 7-9: Migrate one at a time. Months 10-12: Remove old model.

[Results] Measurable outcomes

##### Results

40% faster feature delivery. 35% fewer bugs. Each team owns their domain fully.

Key improvements achieved:

  • System handles 10x burst load without degradation
  • Delivery latency reduced from seconds to milliseconds
  • Zero message loss during traffic spikes
  • Operational complexity reduced by 60%

[Anti-patterns] What could have gone wrong

##### Shared Model

Velocity continues declining. Each business line bottlenecked by others.

  • Over-engineering the initial solution
  • Ignoring operational constraints during design
  • Premature optimization without load testing
  • Skipping failure mode analysis

[Applicability] Where this pattern applies

##### Signs Needed

Giant models. Changes require understanding unrelated domains. Bugs cascade.

Every system is different. Context always matters.