Enum EmbedderBackend 

#[non_exhaustive]
pub enum EmbedderBackend {
    LlamaCpp,
    OpenAiRemote,
    OllamaRemote,
    Noop,
    Unresolved,
}

Which embedder backend Lunaris::open actually resolved in this process.

W1.2 (2026-08-21). The Noop arm is a silent degradation: every vector is zeros, so hybrid recall collapses to BM25 + insertion-order tie-breaks while every surface keeps answering 200. Until this enum existed the only evidence was one tracing::warn! fired once per process — which lunaris-server’s /readyz could not see, so a server built without llamacpp (the workspace entry sets default-features = false) reported itself READY with a zero-vector embedder. dim() cannot distinguish the cases: NoopEmbedder reports a non-zero dim on purpose so the operator’s existing FT.CREATE index geometry stays valid.

This is deliberately a structural signal. A probe must never call embed_batch to find out — a wedged ggml pool cannot be cancelled from async Rust, so an inference-based probe wedges on a timer forever (see lunaris-server/src/readiness.rs module docs).

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

LlamaCpp

In-process llama.cpp over a staged GGUF — the shipped local path.

OpenAiRemote

Remote OpenAI-compatible /embeddings endpoint.

OllamaRemote

Remote Ollama endpoint (operator escape hatch).

Noop

Zero-vector fallback. Real vectors are NOT being produced.

Unresolved

Lunaris::open has not run in this process — the handle was built through a with_parts* test seam, so no backend was resolved. Callers must treat this as “unknown”, never as “degraded”.

Implementations

impl EmbedderBackend

pub const fn as_str(self) -> &'static str

Stable lowercase identifier, safe to compare against across releases.

This is the SDK-facing spelling: the Python and TypeScript bindings cannot carry a Rust enum, so Lunaris::embedder_backend hands them this string. Treat these values as API — changing one is a breaking change for every caller doing if backend == "noop".

pub const fn produces_real_vectors(self) -> bool

Whether this backend produces real vectors.

Noop does not — every vector is zeros, so hybrid recall silently collapses to BM25 plus insertion-order tie-breaks while every surface keeps answering successfully. Unresolved means open has not run in this process, which is “unknown”, NOT “degraded”, so it answers true here rather than raising a false alarm in a test-seam handle.

Trait Implementations

impl Clone for EmbedderBackend

fn clone(&self) -> EmbedderBackend

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for EmbedderBackend

impl Debug for EmbedderBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for EmbedderBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for EmbedderBackend

impl PartialEq for EmbedderBackend

fn eq(&self, other: &EmbedderBackend) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for EmbedderBackend