When you notice the same code pattern appearing in multiple places, extract it into a reusable function rather than copy-pasting. Duplicated code is error-prone and harder to maintain. Look for repeated logic, data structure creation patterns, or similar operations that can be abstracted. For example, instead of repeating fold operations: ```ocaml (* Duplicated pattern *) taints_and_shapes |> List.fold_left (fun acc (taints, shape) -> acc |> Taints.union taints |> Taints.union (Shape.gather_all_taints_in_shape shape)) ``` Extract it into a helper function that can be reused across multiple locations. Similarly, instead of copy-pasting record definitions: ```ocaml (* Instead of duplicating this structure *) { source_kind = "semgrepignore"; filename = custom_filename; format = Gitignore.Legacy_semgrepignore; } ``` Create a parameterized function: ```ocaml let semgrepignore_files ~filename = { source_kind = "semgrepignore"; filename; format = Gitignore.Legacy_semgrepignore; } ``` This approach improves code organization, reduces maintenance burden, and prevents inconsistencies that arise from manual copying.