Paper 2 · Question 14

A: Allowing both instances to make independent, potentially contradictory modifications to the same file risks complex merge conflicts that are difficult to resolve correctly. Coordinating changes to shared files upfront is safer.

B: Sequencing modifications to shared files avoids merge conflicts. Instance A completes its changes to OrderService.java and merges. Instance B then rebases onto the updated main, seeing Instance A's changes, and makes its modifications with full awareness of the current state. This is the standard coordination pattern for parallel Claude Code instances modifying shared files.

C: A dedicated shared-file instance adds coordination complexity without clear benefit. It needs to understand both extraction contexts to make correct modifications. Sequential merging with rebasing is simpler and more reliable.

D: Git does not have built-in file locking for standard workflows. While Git LFS supports file locking, it is designed for binary files, not source code coordination. Sequential merge-and-rebase is the standard approach for coordinating parallel branches.