Personas
A party the running system serves. Personas are the axis
capabilities are stated against — every capability takes the form "a
<persona> can <achieve something>" — so a system with no personas cannot state a single
one.
Defined once, system-wide. Internal parties are first-class, not an afterthought. A persona is not a job title, and one human may be several of them in a day. A party that acts on the change is a discipline, never a persona.
| Persona | The system serves them by |
|---|---|
| End user | Doing the thing they came for |
| Administrator | Letting them configure it — tenants, permissions, settings |
| Operator | Letting them run it — deploy, scale, restart, respond when it misbehaves |
| Support agent | Letting them see what a user saw, and put it right |
| Auditor | Letting them establish what happened, after the fact |
| Integrator | Giving them a stable contract to connect another system to |
| Consuming developer | Giving them something to build on — a package, an API, a library |
These are examples. The practice names no personas. Specifying the actual set is a required act of applying the practice to a system — until it exists, not one capability can be stated. The practice supplies only the test: does the running system serve them?
A new system still has personas. A project with no users has the parties it is being built for. Naming them before anyone arrives is what makes the first capability writable, and it is a cheaper conversation than the one that happens after the first release goes to somebody nobody described.
Admit builders here and the sorting test breaks. The test asks whether something gives a named persona an outcome they did not have. Let designers or developers be personas and it starts asking whether a change gives designers a new outcome — a question the running system has no opinion about, and one that would let internal convenience be stated as a capability.
The same word can land on either branch. A developer building the system is a discipline; a developer consuming what it publishes is a persona. Nothing about the person changed — the object did, and that is the only test there is.
Where a bare name could be read as either, it is not precise enough. Qualify it until it can only be one — Development and Consuming developer, never Developer twice.