Engineering / research
Specify and verify service mechanisms
Translate service contracts into state models, safety invariants, liveness assumptions, and executable checks while making abstraction limits explicit.
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Inside this module
Module 01 research
Specify and verify service mechanisms
Translate service contracts into state models, safety invariants, liveness assumptions, and executable checks while making abstraction limits explicit.
- 01
Specify service states and the transitions that are actually atomic
Turn a reservation contract into explicit state, guarded actions, unchanged fields, and environment behavior before checking correctness.
27 min - 02
Prove initiation and preservation with a strong enough invariant
Separate the desired safety property from an inductive strengthening, and interpret a failed preservation check before calling it a reachable bug.
28 min - 03
State the scheduling assumptions that make progress possible
Distinguish safety, liveness, weak fairness, and strong fairness using an explicit starvation cycle rather than an optimistic scheduler story.
29 min - 04
Report the state and execution bounds behind a successful check
Distinguish bounded execution search, complete exploration of a finite instance, and an unbounded inductive argument.
28 min - 05
Attach temporal obligations to stable logical request identities
Specify every accepted request's terminal outcome, distinguish eventual resolution from success and deadlines, and avoid aggregate-progress loopholes.
28 min - 06
Relate concrete service steps to an abstract contract
Define an explicit state mapping, account for internal stuttering steps, and separate safety simulation from progress preservation and observable responses.
29 min - 07
Reduce interchangeable identities only when the property permits it
Use permutation symmetry to explain state-space reductions, while preserving distinguished roles, transitions, observations, and tool-specific liveness limits.
28 min - 08
Find a legal sequential explanation that respects real-time order
Check concurrent call histories against a sequential object contract, including overlapping completions, pending calls, and uncertainty in captured order.
29 min - 09
Turn an abstract failure trace into a controlled fault schedule
Map counterexample actions to implementation barriers and durable observations, then reproduce the relevant crash or message schedule without confusing timing luck with evidence.
28 min - 10
Keep a checked specification connected to the shipped service
Distinguish model correctness, implementation refinement, trace checking, and operational evidence while maintaining an explicit assumption and artifact ledger.
29 min