Blast Radius Before You Edit

Safe Surgery on System Files · Shipped · workstation

Config dependency graph showing exactly which services break if you change a file, before you touch it.

Before modifying any system configuration file, Halbert can calculate its blast radius — the set of services, mount points, and other config files that directly depend on it. This turns a blind edit into an informed decision.

The ConfigEdgeExtractor builds a dependency graph by parsing systemd unit dependencies, config file Include/Import directives, fstab device-to-mountpoint mappings, and absolute-path file references. The BlastRadiusCalculator traverses this graph to return shallow (direct) dependents for any given config path.

Limits and invariants

Currently returns shallow (direct) dependents only — deep transitive traversal is a future enhancement.

Where this lives

• halbert_core/halbert_core/config/edge_extractor.py
• halbert_core/halbert_core/findings/blast_radius.py