DryRuns

DryRuns, often written as dry run or dry-run, is a term used across computing and project management to describe executing a procedure in a non-destructive or non-committal way. The goal is to verify the sequence of steps, decisions, or changes without applying them to the live system or data.

In software development, a dry run means running code in a way that logs actions and decisions without altering persistent state. This can involve using a dry-run flag, a test environment, or mock services so that inputs produce outputs without writes, commits, or external side effects. Dry runs help developers validate control flow, error handling, and user-facing messaging before deployment.

In databases and migrations, a dry run may simulate a migration or schema change and reveal the proposed alterations without applying them. Output typically includes the list of changes, affected tables, and potential conflicts, enabling review before execution.

In infrastructure as code and deployment workflows, dry-run modes simulate changes to the environment. Examples include commands that preview alterations (such as plan or preview stages) without applying them, allowing teams to detect misconfigurations or unintended consequences in advance.

Benefits of dry runs include early error detection, safer change validation, and cost savings by avoiding unintended impacts. Limitations arise because not all interactions can be faithfully simulated; environment differences, non-deterministic behavior, and external systems may still reveal issues only after real execution.

See also: dry run, simulation, sandbox, preflight checks, staging environment.