> Stack
The Legacy Gravity Stack
Incidents where modernizing architecture is defeated by the invisible weight of undocumented business rules.
"The new system was beautifully designed. The old system had the revenue."
What this stack means
This stack tracks the painful reality that legacy systems survive because they encode the messy truth of the business.
Why this stack exists
Because developers underestimate the complexity of existing systems and overestimate the clarity of the rewrite.
▶ Common Failure Patterns
- •the second-system effect
- •strangler fig failure
- •undocumented edge case explosion
- •database coupling
- •feature parity paralysis
Prevention Checklist
- Map the existing system's behavior, not just its code.
- Migrate incrementally, verifying functionality at each step.
- Do not attempt a 'big bang' rewrite.
Detection Signals
- The rewrite project repeatedly missing its deadlines.
- Discovering critical business logic hidden in stored procedures.
- Users refusing to migrate to the new system because it lacks 'that one feature'.
Related Categories
Related Stacks
Incidents in The Legacy Gravity Stack
Reference
The Legacy Gravity StackArchitecture and Legacy
Legacy System Was Load Bearing
"The chaos was predictable."
Pattern: adapter permanence
Read Incident →
Reference
The Legacy Gravity StackArchitecture and Legacy
Migration Had a Personality
"The chaos was predictable."
Pattern: adapter permanence
Read Incident →
Reference
The Legacy Gravity StackArchitecture and Legacy
The System Remembered the Old Decision
"The chaos was predictable."
Pattern: adapter permanence
Read Incident →
Reference
The Legacy Gravity StackArchitecture and Legacy
The Monolith Was Not the Villain
"The chaos was predictable."
Pattern: adapter permanence
Read Incident →
The Legacy Gravity Stack - Frequently Asked Questions
What is this stack?
Old systems that refuse to be replaced.
AI Summary
Incidents where modernizing architecture is defeated by the invisible weight of undocumented business rules.