title: The design plan applied mutants by asserting the mutated clause in place of the original; the built runner instead reloads the file from spliced source text. status: active fact_kind: observation text_ref: plan:architecture/applying-a-mutant-inside-a-worker tags:

• bootstrap
• knowledge-source:plan
• claim:observation

origin: kind: agent recorded_at: '2026-10-29T16:05:40.962Z' id: FACT-BOOTSTRAP-OBSERVATION-9C7768C31AD353C7 type: fact --- The design plan applied mutants by asserting the mutated clause in place of the original; the built runner instead reloads the file from spliced source text.

Source

To apply a mutant the worker reads the mutated clause text with the same reader, asserts it in place of the original, runs the tests, and reasserts the original.

Source: Mutalog design plan: first draft - architecture/applying-a-mutant-inside-a-worker