Impact analysis example
What breaks when you change Convex?
Real arc impact output on Convex — same structure as the homepage demo. Know blast radius before you merge.
Project: Convex · Score: 59.6/100 (Moderate technical debt) · 245 modules · 1,155 edges
Engineering decision simulation
Validation procedure 01 · merge vs. hold before output
Before arc impact
You plan a change to a high fan-in module in Convex. Would you merge without knowing blast radius?
Typical answer: hold — need dependency context.
After arc impact
Structured output below: score, hotspots, corridors, and high-risk modules — same field schema as the homepage proof.
Decision: confirm hold, narrow change, or inspect paths first.
Published as part of the validation record. Run locally: arc impact <file-you-are-changing>
Architectural Risk Map
Where risk accumulates by control surface — drill down Surface → Substrate → Mechanism → Evidence.
See control surfaces →Dependency evidence
Architecture visualization
Diagrams are generated from ArcSight analysis data. Dependency graph and risk map show key modules; subsystem view shows high-level structure.
Architecture score & metrics
Score: 59.6/100 · Stability: 3/100 · Status: critical · Confidence: 100%
- Dependency cycles: 100+
- Duplicate authorities: 81
Modules to inspect
One row per module. Fan-in is direct dependents. Blast radius is downstream modules reachable from that file.
- src/values44 dependents
- src/values/value23 dependents
- src/server/api18 dependents
- src/server/data_model17 dependents
- src/common12 dependents
- src/values/validator7 dependents
- src/values/validators6 dependents
- src/server/system_fields5 dependents
- src/values/value186 modules
- src/common186 modules
- src/values178 modules
- src/values/validator178 modules
- src/values/validators178 modules
- src/server/data_model158 modules
- src/server/system_fields158 modules
- src/server/api143 modules
| Module | Fan-in | Blast | Risk |
|---|---|---|---|
| src/values/value | 23 | 186 | CRITICAL |
| src/common | 12 | 186 | CRITICAL |
| src/values | 44 | 178 | CRITICAL |
| src/values/validator | 7 | 178 | CRITICAL |
| src/values/validators | 6 | 178 | CRITICAL |
| src/server/data_model | 17 | 158 | CRITICAL |
| src/server/system_fields | 5 | 158 | HIGH |
| src/server/api | 18 | 143 | CRITICAL |
| src/values/errors | 5 | CRITICAL | |
| src/values/base64 | 2 | CRITICAL |
Architectural gravity centers
src/values/value— concentrates too many responsibilitiessrc/values/value— shared utility hubsrc/values/value— sits on a dependency cyclesrc/common— sits on a dependency cyclesrc/values— concentrates too many responsibilities
CLI workflow
Scan → Fix → Finish → Watch. Nothing else required.
arc scanFind issuesarc fixApply fixesarc finishResolve remainingarc watchKeep clean
Key takeaways
- •Structural scan reports dependency cycles — inspect impact paths before refactors that cross module boundaries.
- •High fan-in modules are change-risk zones; run
arc explain <path>before refactoring. - •Run the full workflow (analyze, hotspots, explain, impact, snapshot, drift) in your repo for deterministic architecture insights.
Run ArcSight on your repo
Install the CLI and run analyze, then hotspots and explain for the same workflow.
This case study is generated from ArcSight analysis data. View short analysis. View all analyses