vocabulary:
  name: wasmCloud Vocabulary
  description: >-
    Domain vocabulary for wasmCloud, the CNCF incubating platform for building
    and running distributed applications with WebAssembly components. Covers
    runtime concepts, deployment patterns, and lattice management operations.
  version: '1.0'
  created: '2026-05-03'
  modified: '2026-05-03'
  tags:
    - Cloud Native
    - CNCF
    - WebAssembly
    - WIT
  terms:
    - term: Lattice
      definition: >-
        A flat, self-forming, self-healing mesh network of wasmCloud hosts that
        communicate over NATS. The lattice provides the distributed substrate
        for running WebAssembly components and capability providers. Each
        lattice is scoped to a NATS account.
      tags:
        - Core Concept
        - Networking
    - term: Component
      definition: >-
        A WebAssembly component that encapsulates portable business logic. In
        wasmCloud, components are identified by OCI image references and run
        as concurrently-scalable instances on hosts. Components declare their
        capabilities using WIT interfaces.
      tags:
        - Core Concept
        - WebAssembly
    - term: Capability Provider
      definition: >-
        A host-native plugin that implements one or more WIT interface packages
        to provide infrastructure capabilities (HTTP server, key-value store,
        messaging, blobstore, etc.) to components. Providers are identified
        by OCI image references and run as singleton processes per host.
      tags:
        - Core Concept
        - Capabilities
    - term: Link Definition
      definition: >-
        A named association between a component and a capability provider (or
        another component) that grants the source component permission to call
        the target's interfaces. Links carry optional configuration values
        passed to the target at link time. Links are scoped by WIT namespace,
        package, and link name.
      tags:
        - Core Concept
        - Security
    - term: Host
      definition: >-
        A wasmCloud runtime process that manages the lifecycle of components
        and capability providers within a lattice. Hosts are identified by
        NKey public keys and can be labelled for scheduling constraints.
      tags:
        - Runtime
    - term: wadm
      definition: >-
        wasmCloud Application Deployment Manager — the declarative GitOps
        reconciler for wasmCloud. wadm reads OAM application manifests and
        continuously reconciles the actual lattice state against the declared
        desired state, handling scaling, upgrades, and self-healing.
      tags:
        - Tooling
        - Deployment
    - term: wash
      definition: >-
        WAsmcloud SHell — the primary CLI tool for wasmCloud development and
        operations. wash bundles a local wasmCloud host, NATS server, and wadm
        for development, and provides commands to build, deploy, and manage
        applications and components.
      tags:
        - Tooling
        - CLI
    - term: WIT
      definition: >-
        WebAssembly Interface Types — the interface definition language used
        to describe the APIs that WebAssembly components import and export.
        WIT packages group related interfaces (e.g., wasi:http, wasi:keyvalue)
        and form the contract between components and capability providers.
      tags:
        - Standard
        - Interfaces
    - term: WASI
      definition: >-
        WebAssembly System Interface — a family of standardized WIT interface
        packages maintained by the W3C WebAssembly Community Group. WASI 0.2
        (the Component Model) is the foundation for wasmCloud's portability
        guarantees. Includes wasi:http, wasi:keyvalue, wasi:blobstore, and more.
      tags:
        - Standard
        - Interfaces
    - term: OAM
      definition: >-
        Open Application Model — a vendor-neutral, runtime-agnostic application
        specification format originally developed by Microsoft and Alibaba.
        wasmCloud uses the OAM Application and Component kinds in wadm manifests
        to define distributed application topology.
      tags:
        - Standard
        - Deployment
    - term: Lattice Control Interface
      definition: >-
        The NATS-based request/reply API that operators and tooling use to
        control wasmCloud hosts. Published on well-known subjects under
        wasmbus.ctl.v1.{lattice}. Supports querying hosts, scaling components,
        starting/stopping providers, and managing link definitions.
      tags:
        - API
        - NATS
    - term: Spread Scaler
      definition: >-
        An OAM trait that specifies how many replicas of a component or provider
        should run and across which hosts (using label constraints). wadm uses
        spread scalers to distribute workloads according to placement policies.
      tags:
        - Deployment
        - Scaling
    - term: NKey
      definition: >-
        Ed25519-based cryptographic key pair used throughout wasmCloud for
        identity. Hosts, components, and operators are all identified by NKey
        public keys. NKeys provide both identity and signing capability without
        requiring certificates.
      tags:
        - Security
        - Identity
    - term: CloudEvent
      definition: >-
        A CNCF-standard event format used for wasmCloud host event emissions.
        Events such as component_scaled, provider_started, and host_heartbeat
        are emitted on the lattice event stream (wasmbus.ctl.v1.{lattice}.evt.{hostId})
        in CloudEvents format for observability and integration.
      tags:
        - Observability
        - CNCF