GBrain Code v0.2.0

Repository Twin research artifact

This release adds a dual-snapshot structural Repository Twin around GBrain Code:

• immutable T0/T1 snapshots and signed deltas;
• tombstone evidence for relationships removed by a change;
• source-cited bounded impact rankings;
• five reproducible Twin mechanics fixtures;
• an equal-budget executable impact scheduling lab;
• documented prior art, limitations, falsification criteria, and evaluation boundaries.

Reproduced results

• Signed delta recall: 1.00
• Twin impact recall@10: 1.00
• Changed-state-only impact recall@10: 0.50
• Planned current-only misses confirmed: 2/2
• Synthetic executable detection: 1.000 Twin vs 0.351 general/current-only at the same scenario budget

These are narrow results on public synthetic fixtures. They do not establish better agent patches, runtime causality, or general benchmark leadership. The experimental code remains outside the MCP surface.

GBrain Code v0.1.0

First experimental release of the evidence-only repository cartographer.

• Question-scoped maps across TypeScript/JavaScript, Python, and SQL
• Active/superseded migration lineage
• Supabase RPC/table relationships, including small local wrappers
• Diff-aware ripple and related-test audit
• Five-tool MCP surface with no answer generation or autonomous editing
• Evaluation protocol and position paper

This is an alpha research prototype. The release makes no benchmark superiority claim.