Blast radius
Graphify glossary
Everything transitively affected by a change — the callers of a function, their callers, and the configs and tests that reference them.
Blast radius is everything transitively affected by a change: the callers of a function, the callers of those callers, the configs that reference them, the tests that exercise them. It's the honest answer to 'what could this edit break?' — and 'transitively' is the operative word. The direct callers are the easy part; the risk lives two and three hops out, where nobody remembers the dependency exists.
Computing a blast radius is a traversal: start at the changed node, follow edges backwards, and keep going until the frontier stops growing. A graph does this directly and exhaustively. Doing the same with text search means recursively grepping for every symbol you find, manually filtering name collisions at each level, and trusting yourself not to miss a branch — which is why in practice nobody does it, and blast radius gets estimated by intuition instead. Intuition is exactly what fails on the dependencies nobody remembers.
In Graphify, blast radius shows up in three places. GRAPH_REPORT.md flags god nodes — the nodes whose blast radius is the whole codebase — so you know the danger zones before you edit. graphify prs uses graph structure to triage open PRs and flag merge-conflict risk when changes land in overlapping territory. And in Graphify Enterprise, the same computation backs merge-gate review: checking what a PR actually touches, transitively, before it merges.
For an AI assistant, blast radius is the difference between confident and careful. An assistant that can ask 'what depends on this?' before editing writes different code than one that finds out from the test suite — it updates the callers it would otherwise have missed, and it tells you when a change is bigger than it looks.
Related terms
- Traversal / hop — Following edges from node to node — one hop is a single edge, a traversal is a path of them. How graphs answer multi-step questions.
- God node — A node with a disproportionate number of edges — the module everything imports — where changes carry the most risk.
- Community (cluster) — A group of nodes densely connected to each other and only loosely connected to the rest of the graph — usually a real subsystem like auth or billing.