Intermittent file busy errors during concurrent terramate generate on shared stack templates

Goal

Determine whether concurrent terramate generate invocations writing to overlapping stack directories should serialize access through Terramate's template compilation pipeline, or whether each invocation manages its own filesystem locking.

Constraints

Terramate stores templates and generated HCL on the local filesystem. Parallel CI/CD runs or developer workflows targeting the same stack definitions can produce intermittent file busy errors. Documented behavior does not state whether this is a supported concurrency boundary, and results may differ by operating system, filesystem type, and Terramate CLI version.

Questions

• Is concurrent generation against shared stack templates an unsupported configuration?
• Should callers wrap parallel terramate generate calls with external locking, or does Terramate serialize access internally?
• Which filesystem and CLI version combinations are affected by the file busy condition?