The Playbook
The playbook
Start from what you already run, what you noticed, where you are, or what you are building. Each play names the doubt, the sensor to point at it, and where to go next. The catalog is the reference; this is the route through it.
Not sure what to do next? Tick what you already run and the page says what it closes and what to add.
Tick the sensors you run. The page says which of the 19 doubts they close, which are still open, and which one addition would close the most of what is left. Two sensors that close the same doubt count once; a sensor with no doubt edge in the vocabulary counts for nothing here, however useful it is.
- Wrong logic
- Unasserted execution
- Unjudged observation
- Unspecified property
- Wrong specification
- Missing behavior
- Emergent failure
- Untested conditions
- Correlated blind spot
- Late effects
- Not internally consistent
- Unintended change
- Unreached by tests
- Does not run where deployed
- Falls over with a dependency
- Cannot carry the load
- Nobody knows where the coupling is
- Nobody knows where the risk sits
- Nobody can find out why
What you noticed
Something is wrong and you can say what it looks like. Each play names the doubt behind it, the sensor to point at it, and where to go if the doubt survives.
- Tests pass, bugs still shipthe doubt: unasserted execution
- The bug was in an input nobody triedthe doubt: wrong logic
- Production says 200 and the answer was wrongthe doubt: unjudged observation
- Something changed that nobody meant to changethe doubt: unintended change
- Every service passes alone, the system fails togetherthe doubt: emergent failure
- It worked in CI and died on deploythe doubt: does not run where deployed
- One slow dependency took everything downthe doubt: falls over with a dependency
- The agent wrote it, the agent reviewed it, both agreedthe doubt: correlated blind spot
- The same three files keep causing incidentsthe doubt: nobody knows where the risk sits
- Nobody can say why the code is like thisthe doubt: nobody can find out why
Where you are
What you already run decides what to add first. Each play starts from a set of sensors and adds them in the order that closes a new doubt at every step.
What you are building
A minimal stack for one shape of system, composed by distinct doubts closed rather than one sensor per family.