Terms in context

These definitions use the project’s events and boundaries. A term is useful when it helps identify what changed, which component owns it, and what evidence supports the result.

Application and payment terms

Term	Meaning here	Where you encounter it
Source of truth	PostgreSQL’s durable mapping from code to destination, plus optional payment audit fields. Redis is not authoritative.	A redirect falls back after a cache miss; creation always consults the database.
Acceleration dependency	A dependency that improves performance while a defined request path can bypass it.	Redis accelerates redirects after initial readiness; PostgreSQL can resolve an uncached code.
Liveness	The process can serve a basic response without checking its dependencies.	Application and signer /livez return 200 while dependency readiness can fail.
Readiness	The process currently meets its conditions for useful service.	App /ready requires PostgreSQL always and Redis before first success; signer /health reflects bootstrapped wallet state.
Startup probe	Kubernetes’ initial probe budget before regular readiness/liveness handling.	The application deployment uses /ready, so a starting process must satisfy initial database and cache conditions.
Cache miss	No usable cached destination was returned, including a read exception.	url_shortener_cache_misses_total includes ordinary misses and unavailable-cache fallback.
x402 challenge	An HTTP 402 response describing server-owned payment terms.	A new paid /shorten request without a header receives PAYMENT-REQUIRED.
Permit2	The authorization mechanism used for signed token-transfer permission.	The signer creates EIP-712 authorization with token, amount, spender, nonce, expiry, and recipient witness.
Witness	Recipient-bound data included in the signed authorization.	The authorization binds the configured merchant destination rather than allowing callers to choose it.
Facilitator	The configured external adapter that verifies the signed payment and submits settlement.	App /shorten calls facilitator /verify before /settle; the signer performs neither call.
Settlement	A facilitator-reported successful payment transfer with a validated transaction identifier.	The application persists only after validating settlement; success alone does not guarantee its database insert will succeed.
Replay	Reuse of an already-associated settlement identifier for a different destination.	PostgreSQL’s unique index blocks the insertion; the route returns 409 after locating the conflicting settlement.
Atomic unit	An integer amount in the token’s smallest denomination.	Payment amounts are decimal strings in requirements and integers in signing, rather than floating-point prices.

The signer is ready when at least one configured slot has completed bootstrap. The paid load client separately requires enough bootstrapped wallets for its virtual users and enough cached balance for the bounded run. Thus “signer ready” does not mean “every planned paid load configuration can run.” See paid requests and signer failure.

Delivery and identity terms

Term	Meaning here	Where you encounter it
Image digest	Immutable identifier for image content.	Kargo renders digest-qualified images rather than relying on a mutable tag.
Signature identity	The CI identity associated with keyless signing and verification.	Publication verifies Cosign signatures; present stage configuration does not independently enforce them.
Freight	Kargo’s candidate record for selected artifact versions.	A stage promotes particular Freight, not a free-floating dashboard result.
Promotion	Selecting a candidate and advancing environment configuration through the stage’s configured steps.	Development is automatic; staging and production-like transitions are manual.
Reconciliation	A controller brings actual Kubernetes resources toward declared Git state.	Argo CD follows Kargo-rendered environment branches.
Rendered revision	Git commit containing generated environment manifests.	It binds configuration output and must be tracked alongside application source and image digest.
AnalysisRun	The verification resource used to execute and record configured stage analyses.	Staging gate evidence names the exact AnalysisRun and its enclosing gate Job.
Eligibility	The normal downstream path may select Freight whose upstream verification succeeded.	A staging pass permits normal prod-like selection; it does not automatically trigger promotion.
Manual approval	A separate operator override of Freight eligibility.	It must not be interpreted as proof that upstream verification passed.
prod	Production-like testnet in this owned lab.	It is not public production or a mainnet environment.

An application source revision, chart revision, rendered revision, signer digest, gate-runner digest, load-generator identity, and run identifier describe different objects. The artifact contract explains why retaining one convenient commit or tag does not bind them all.

Experiment and evidence terms

Term	Meaning here	Where you encounter it
Pod failure	A bounded Chaos Mesh failure of a selected staging dependency pod.	The PostgreSQL, Redis, and signer scenarios each request 60s, mode: one.
Blast radius	The resources and behaviors the experiment can affect.	Namespace and component selectors narrow targeting; shared-cluster resources remain a lab limit.
Useful traffic	Requests that exercise the relevant behavior beyond probes.	The gate requires a run-scoped paid creation and redirect marker before injection; selected score rules count non-probe requests.
Observation window	The bounded interval used for fault and recovery measurements.	Scorecards carry start, actual injection anchor, fault duration, settle time, and end.
Scorecard	A schema-shaped record of checks, expressions, units, observations, reasons, and candidate/run metadata.	It explains why an experiment passed or failed.
Cleanup	Removal and absence checks for the current run’s workflow and load Job.	It remains a requirement after measurement; a score can pass while cleanup causes the enclosing gate to fail.
Fail closed	Missing prerequisites or insufficient evidence prevent a pass.	Missing targets, unusable telemetry, and uncertain cleanup are not treated as healthy observations.
Provenance	Identity, timing, source, and review information attached to an artifact.	Screenshot capture time and displayed measurement window are recorded separately.

Use the failure workflows for concrete examples and the failure model for result categories such as pass, fail, blocked, unavailable, and not collected.