Glossary | ESSOne line for each term the ESS documentation uses, with the page that defines it.ESSreferenceessreferenceadopterdevelopertry-spec-driven-developmentreference

Glossary

Each term has one line here and a link to the page that defines it. The linked page is the authority; this list only helps you find it.

Term	Meaning	Defined in
Actor	Who may invoke which commands.	The model
Aggregate view	A view with `group_by:` that reports counts, sums and extremes over one entity's rows.	Aggregate views
Ambient precondition	A command every command of the system runs inside, such as an open session.	Ambient preconditions
Authored scenario	A conformance scenario a person wrote as an `ess-scenario/*` document, joined to a suite only when `--scenarios` names it.	Author scenarios
Binding	An event-to-command reaction across contexts, including what happens when it fails.	Bindings
Command	The only way state changes; it declares its input and its outcomes.	The model
Compiled model (IR)	The normalized intermediate representation every name resolves in; compiling the same source twice gives the same bytes.	The pipeline
Component	A unit of ownership over domains, which can become a module or a process without changing what it owns.	Logical, interface and delivery owners
Concurrent history	A recorded run of several clients, with each call's invoke and return instants, checked against the model.	Check a concurrent history
Consistency	A view's declaration of whether a generated assertion reads it immediately or eventually.	View consistency
Conversion	A declared reason for a binding to carry a value from one context's type into another's.	Conversions
Declared coverage	An opt-in suite form that retains its declared scope, the selected scenarios and every refusal, so a report can qualify what it covers.	Declared coverage
Deliverable descriptor	An `ess-component/1` document naming a deliverable's source paths and release units.	Component delivery
Digest	A hash identifying only the bytes its producer defines; several digest kinds exist.	Which digest is this?
Disposition	What synthesis does with one capability: generate it, name it as an obligation, or refuse it with a reason.	The synthesis plan
Display name	The human-readable name generated documentation and a UI show.	Names
Domain	One bounded context: its types, entities, commands, events, errors and views.	Layout
Entity	Identity-bearing state with a lifecycle, invariants and declared relations.	The model
Entrypoint	One physical way into an implementation, an argv or an HTTP(S) URL, recorded in a realization.	Record a realization
Error	A declared domain refusal.	The model
Event	A fact a command's outcome emits.	The model
Explorer	Seeded random command sequences run against your target and checked after every step.	Explore
Format version	The number in `format:` that moves when meaning, identity or the persisted shape changes.	Format version history
Guard	A predicate on an outcome that decides when that branch is taken.	Guards and outcome selection
Impact	What a semantic delta invalidates: constructs, generated artifacts or suite scenarios.	Find the work owed again
Interpreted target	The built-in target that runs a suite against the specification itself.	Run a supported target
Invariant	A rule on a type or entity that travels into every projection.	Invariants
Locator	The name anything outside the specification uses to point at a construct.	Names
Mutant	A copy of the specification with one rule changed, used to test whether a suite notices.	Mutation audit
Normalization recipe	An `ess-normalization/*` document naming the ordered stages that turn external input into model values.	Explicit normalization
Obligation	A capability the specification does not fully determine, implemented by hand in a realization.	Realizations
Outcome	One declared result of a command, including each refusal branch.	Declared outcomes
Predicate	A condition over facts, written as a compact string or a structured mapping.	Predicates
Projection	A generated artifact derived from the compiled model: documentation, site, JSON Schema, OpenAPI or AsyncAPI.	Projections
Qualified name	The dotted name only the specification itself uses, such as `billing.invoice.CreateInvoice`.	Names
Reach	Where a component's callers are: `in_process`, `network` or `command_line`.	Reach, entrypoints and identity
Realization	A document naming the immutable artifacts that implement an exact specification and how they are entered.	Record a realization
Report	The standalone record of what a run's scenarios observed against a named target and specification digest.	What the report proves
Scenario	One semantic check in a suite: steps against a target and the result they require.	The conformance suite
Semantic delta	What moved in meaning between two revisions of a specification.	Compare revisions
Suite	The deterministic set of scenarios a specification requires of an implementation.	Synthesize a suite
Survivor	A mutant no scenario notices: a declared rule the suite does not pin down.	Mutation audit
Synthesis plan	The language-neutral plan that gives every capability of a specification one disposition.	The synthesis plan
System	The root of a specification: its name, version and domains.	The model
Target	The implementation a suite runs against, built in or your own.	Runners and reports
Topology	Each component's runtime requirements: replica bounds, statefulness and required resources.	The model
Value expression	A `payload:` or `sets:` value taken from more than the input or a literal.	Value expressions
View	A read model: what it shows, filtered by what.	The model
Wire name	The name HTTP paths, topics and generated JSON use.	Names