Road to State Machines Part VI - But What If Independent Work Finishes in a Different Order?
Coordinate independent carrier and inventory checks with correlated results, async task groups, and explicit recovery boundaries.
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Articles and notes on software design, Python, and the web.
Road to State Machines Part I - Designing Systems When the Past Determines What Is Allowed Next
How lifecycle state summarizes an order’s past and determines its allowed next actions, and why recording status alone cannot enforce correctness.
Road to State Machines Part II - But How Do We Prevent Impossible Changes?
Enforce valid order states, invariants, preconditions, and permitted transitions with Python checks that reject invalid changes before mutation.
Road to State Machines Part III - But How Do We Represent the Entire Lifecycle as One Behavioral Contract?
Represent an order lifecycle as an explicit finite state machine using Python enums and a shared transition table for operations and available actions.
Road to State Machines Part IV - But How Do We Let Data Influence Transitions Without Turning Every Value into Another State?
Use guards and supporting data to control transitions in an extended finite state machine without multiplying lifecycle states.
Road to State Machines Part V - But How Does the Machine Wait for Something That Happens Later?
Model asynchronous work with waiting states, commands, events, correlation identifiers, timeouts, and a queue that serializes local reactions.