Security Ownership Map Overview Build a bipartite graph of people and files from git history, then compute ownership risk and export graph artifacts for Neo4j/Gephi. Also build a file co-change graph (Jaccard similarity on shared commits) to cluster files by how they move together while ignoring large, noisy commits. Requirements Python 3 networkx (required; community detection is enabled by default) Install with: pip install networkx Workflow Scope the repo and time window (optional --since/--until ). Decide sensitivity rules (use defaults or provide a CSV config). Build the ownership map with scripts/run_ownership_map.py (co-change graph is on by default; use --cochange-max-files to ignore supernode commits). Communities are computed by default; graphml output is optional ( --graphml ). Query the outputs with scripts/query_ownership.py for bounded JSON slices. Persist and visualize (see references/neo4j-import.md ). By default, the co-change graph ignores common “glue” files (lockfiles, .github/ , editor config) so clusters reflect actual code movement instead of shared infra edits. Override with --cochange-exclude or --no-default-cochange-excludes . Dependabot commits are excluded by default; override with --no-default-author-excludes or add patterns via --author-exclude-regex . If you want to exclude Linux build glue like Kbuild from co-change clustering, pass: python skills/skills/security-ownership-map/scripts/run_ownership_map.py \ --repo /path/to/linux \ --out ownership-map-out \ --cochange-exclude "/Kbuild" Quick start Run from the repo root: python skills/skills/security-ownership-map/scripts/run_ownership_map.py \ --repo . \ --out ownership-map-out \ --since "12 months ago" \ --emit-commits Defaults: author identity, author date, and merge commits excluded. Use --identity committer , --date-field committer , or --include-merges if needed. Example (override co-change excludes): python skills/skills/security-ownership-map/scripts/run_ownership_map.py \ --repo . \ --out ownership-map-out \ --cochange-exclude "/Cargo.lock" \ --cochange-exclude "/.github/*" \ --no-default-cochange-excludes Communities are computed by default. To disable: python skills/skills/security-ownership-map/scripts/run_ownership_map.py \ --repo . \ --out ownership-map-out \ --no-communities Sensitivity rules By default, the script flags common auth/crypto/secret paths. Override by providing a CSV file:

pattern,tag,weight

/auth/,auth,1.0 /crypto/,crypto,1.0 */.pem,secrets,1.0 Use it with --sensitive-config path/to/sensitive.csv . Output artifacts ownership-map-out/ contains: people.csv (nodes: people) files.csv (nodes: files) edges.csv (edges: touches) cochange_edges.csv (file-to-file co-change edges with Jaccard weight; omitted with --no-cochange ) summary.json (security ownership findings) commits.jsonl (optional, if --emit-commits ) communities.json (computed by default from co-change edges when available; includes maintainers per community; disable with --no-communities ) cochange.graph.json (NetworkX node-link JSON with community_id + community_maintainers ; falls back to ownership.graph.json if no co-change edges) ownership.graphml / cochange.graphml (optional, if --graphml ) people.csv includes timezone detection based on author commit offsets: primary_tz_offset , primary_tz_minutes , and timezone_offsets . LLM query helper Use scripts/query_ownership.py to return small, JSON-bounded slices without loading the full graph into context. Examples: python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out people --limit 10 python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out files --tag auth --bus-factor-max 1 python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out person --person alice@corp --limit 10 python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out file --file crypto/tls python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out cochange --file crypto/tls --limit 10 python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out summary --section orphaned_sensitive_code python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out community --id 3 Use --community-top-owners 5 (default) to control how many maintainers are stored per community. Basic security queries Run these to answer common security ownership questions with bounded output:

Orphaned sensitive code (stale + low bus factor)

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out summary --section orphaned_sensitive_code

Hidden owners for sensitive tags

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out summary --section hidden_owners

Sensitive hotspots with low bus factor

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out summary --section bus_factor_hotspots

Auth/crypto files with bus factor <= 1

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out files --tag auth --bus-factor-max 1 python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out files --tag crypto --bus-factor-max 1

Who is touching sensitive code the most

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out people --sort sensitive_touches --limit 10

Co-change neighbors (cluster hints for ownership drift)

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out cochange --file path/to/file --min-jaccard 0.05 --limit 20

Community maintainers (for a cluster)

python skills/skills/security-ownership-map/scripts/query_ownership.py --data-dir ownership-map-out community --id 3

Monthly maintainers for the community containing a file

python skills/skills/security-ownership-map/scripts/community_maintainers.py \ --data-dir ownership-map-out \ --file network/card.c \ --since 2025 -01-01 \ --top 5

Quarterly buckets instead of monthly

python skills/skills/security-ownership-map/scripts/community_maintainers.py \ --data-dir ownership-map-out \ --file network/card.c \ --since 2025 -01-01 \ --bucket quarter \ --top 5 Notes: Touches default to one authored commit (not per-file). Use --touch-mode file to count per-file touches. Use --window-days 90 or --weight recency --half-life-days 180 to smooth churn. Filter bots with --ignore-author-regex '(bot|dependabot)' . Use --min-share 0.1 to show stable maintainers only. Use --bucket quarter for calendar quarter groupings. Use --identity committer or --date-field committer to switch from author attribution. Use --include-merges to include merge commits (excluded by default). Summary format (default) Use this structure, add fields if needed: { "orphaned_sensitive_code" : [ { "path" : "crypto/tls/handshake.rs" , "last_security_touch" : "2023-03-12T18:10:04+00:00" , "bus_factor" : 1 } ] , "hidden_owners" : [ { "person" : "alice@corp" , "controls" : "63% of auth code" } ] } Graph persistence Use references/neo4j-import.md when you need to load the CSVs into Neo4j. It includes constraints, import Cypher, and visualization tips. Notes bus_factor_hotspots in summary.json lists sensitive files with low bus factor; orphaned_sensitive_code is the stale subset. If git log is too large, narrow with --since or --until . Compare summary.json against CODEOWNERS to highlight ownership drift.