diff --git a/Cargo.lock b/Cargo.lock
index ab9bbc7..65f5583 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4291,7 +4291,7 @@ dependencies = [
  "lindera-ko-dic",
  "serde_json",
  "serde_json_canonicalizer",
- "serde_yaml",
+ "serde_yaml_ng",
  "time",
  "tracing",
 ]
@@ -4387,7 +4387,7 @@ dependencies = [
  "rusqlite",
  "serde",
  "serde_json",
- "serde_yaml",
+ "serde_yaml_ng",
  "tempfile",
  "time",
  "tracing",
@@ -7794,19 +7794,6 @@ dependencies = [
  "syn 2.0.117",
 ]
 
-[[package]]
-name = "serde_yaml"
-version = "0.9.34+deprecated"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6a8b1a1a2ebf674015cc02edccce75287f1a0130d394307b36743c2f5d504b47"
-dependencies = [
- "indexmap 2.14.0",
- "itoa",
- "ryu",
- "serde",
- "unsafe-libyaml",
-]
-
 [[package]]
 name = "serde_yaml_ng"
 version = "0.10.0"
diff --git a/Cargo.toml b/Cargo.toml
index 7a21f34..93f9984 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -123,9 +123,6 @@ anyhow       = "1"
 thiserror    = "2"
 serde        = { version = "1", features = ["derive"] }
 serde_json   = "1"
-# Golden-fixture loader (P5-1, kebab-eval) parses YAML; pinned in the
-# workspace so future eval-adjacent crates share the same major.
-serde_yaml   = "0.9"
 time         = { version = "0.3", features = ["serde", "macros", "formatting", "parsing"] }
 uuid         = { version = "1", features = ["v7", "serde"] }
 blake3       = "1"
diff --git a/crates/kebab-chunk/Cargo.toml b/crates/kebab-chunk/Cargo.toml
index cdfc8d9..cfc782e 100644
--- a/crates/kebab-chunk/Cargo.toml
+++ b/crates/kebab-chunk/Cargo.toml
@@ -13,7 +13,7 @@ serde_json_canonicalizer   = "0.3"
 blake3                     = { workspace = true }
 anyhow                     = { workspace = true }
 tracing                    = { workspace = true }
-serde_yaml                 = { workspace = true }
+serde_yaml_ng              = "0.10"
 lindera        = { workspace = true, features = ["embed-ko-dic"] }
 lindera-ko-dic = { workspace = true, features = ["embed-ko-dic"] }
 
diff --git a/crates/kebab-chunk/src/k8s_manifest_resource_v1.rs b/crates/kebab-chunk/src/k8s_manifest_resource_v1.rs
index 55e0f66..ca9a2bd 100644
--- a/crates/kebab-chunk/src/k8s_manifest_resource_v1.rs
+++ b/crates/kebab-chunk/src/k8s_manifest_resource_v1.rs
@@ -36,7 +36,7 @@ impl Chunker for K8sManifestResourceV1Chunker {
 
         for slice in slices {
             // Invalid YAML in any document → return 0 chunks for the file.
-            let value: serde_yaml::Value = match serde_yaml::from_str(slice.text) {
+            let value: serde_yaml_ng::Value = match serde_yaml_ng::from_str(slice.text) {
                 Ok(v) => v,
                 Err(_) => return Ok(vec![]),
             };
diff --git a/crates/kebab-chunk/tests/k8s_manifest_resource_v1.rs b/crates/kebab-chunk/tests/k8s_manifest_resource_v1.rs
index a3b981f..930f8e2 100644
--- a/crates/kebab-chunk/tests/k8s_manifest_resource_v1.rs
+++ b/crates/kebab-chunk/tests/k8s_manifest_resource_v1.rs
@@ -156,7 +156,7 @@ fn k8s_multi_doc_emits_one_chunk_per_resource() {
 /// must cause the chunker to return 0 chunks for the entire file.
 #[test]
 fn k8s_invalid_yaml_emits_zero_chunks() {
-    // serde_yaml 0.9 is lenient about duplicate keys (last wins), so use a
+    // serde_yaml_ng is lenient about duplicate keys (last wins), so use a
     // genuine YAML structural error (unclosed flow sequence) to force a parse
     // failure.
     let actually_bad = "apiVersion: v1\nkind: Service\nfoo: [\nbar\n";
diff --git a/crates/kebab-eval/Cargo.toml b/crates/kebab-eval/Cargo.toml
index ab3ab44..d734c00 100644
--- a/crates/kebab-eval/Cargo.toml
+++ b/crates/kebab-eval/Cargo.toml
@@ -15,7 +15,7 @@ kebab-app = { path = "../kebab-app" }
 kebab-store-sqlite = { path = "../kebab-store-sqlite" }
 serde           = { workspace = true }
 serde_json      = { workspace = true }
-serde_yaml      = { workspace = true }
+serde_yaml_ng   = "0.10"
 time            = { workspace = true }
 tracing         = { workspace = true }
 anyhow          = { workspace = true }
diff --git a/crates/kebab-eval/src/lib.rs b/crates/kebab-eval/src/lib.rs
index 1aac28a..c462a2c 100644
--- a/crates/kebab-eval/src/lib.rs
+++ b/crates/kebab-eval/src/lib.rs
@@ -11,7 +11,7 @@
 //! ## Allowed deps (per task spec)
 //!
 //! `kb-core`, `kb-config`, `kb-app`, `kb-store-sqlite`, plus `serde`,
-//! `serde_yaml`, `serde_json`, `time`, `tracing`,
+//! `serde_yaml_ng`, `serde_json`, `time`, `tracing`,
 //! `anyhow`, `uuid`. Retrieval / embedding / LLM crates are NOT
 //! reachable here — every retrieval and `ask` call must go through
 //! `kb-app`.
diff --git a/crates/kebab-eval/src/loader.rs b/crates/kebab-eval/src/loader.rs
index c1d9093..07c0630 100644
--- a/crates/kebab-eval/src/loader.rs
+++ b/crates/kebab-eval/src/loader.rs
@@ -27,7 +27,7 @@ use crate::types::GoldenQuery;
 pub fn load_golden_set(path: &Path) -> Result<Vec<GoldenQuery>> {
     let bytes =
         std::fs::read(path).with_context(|| format!("read golden YAML from {}", path.display()))?;
-    let queries: Vec<GoldenQuery> = serde_yaml::from_slice(&bytes)
+    let queries: Vec<GoldenQuery> = serde_yaml_ng::from_slice(&bytes)
         .with_context(|| format!("parse golden YAML at {}", path.display()))?;
     check_unique_ids(&queries)?;
     check_group_integrity(&queries)?;
diff --git a/crates/kebab-eval/tests/metrics_and_compare.rs b/crates/kebab-eval/tests/metrics_and_compare.rs
index 11aeef3..dfb4441 100644
--- a/crates/kebab-eval/tests/metrics_and_compare.rs
+++ b/crates/kebab-eval/tests/metrics_and_compare.rs
@@ -470,7 +470,7 @@ fn lang_default_is_used_when_omitted_in_yaml() {
     let tmp = TempDir::new().unwrap();
     let golden = tmp.path().join("g.yaml");
     fs::write(&golden, yaml).unwrap();
-    let qs: Vec<GoldenQuery> = serde_yaml::from_str(yaml).unwrap();
+    let qs: Vec<GoldenQuery> = serde_yaml_ng::from_str(yaml).unwrap();
     assert_eq!(qs.len(), 1);
     assert_eq!(qs[0].lang, Lang(String::new()));
 }
diff --git a/crates/kebab-nli/src/lib.rs b/crates/kebab-nli/src/lib.rs
index cc87505..3730612 100644
--- a/crates/kebab-nli/src/lib.rs
+++ b/crates/kebab-nli/src/lib.rs
@@ -53,15 +53,10 @@ pub trait NliVerifier: Send + Sync {
     /// 이 API 로 mDeBERTa-v3 의 `OnlyFirst` dead-end (hypothesis 단독이
     /// 512-token cap 초과 시 truncate 불가) 를 회피.
     ///
-    /// **Default impl 반환 `Ok(0)`** — 기존 mock implementations
-    /// (`MockNliVerifier` 등) 가 trait 확장 후에도 backward-compat
-    /// (compile fail 회피, retry loop immediate 통과). `OnnxNliVerifier`
-    /// 는 real tokenizer 로 *trait impl 블록 안에서* override 해야 함
-    /// — inherent method 는 vtable 미등록 → trait dispatch 시 default
-    /// 호출 → production silent NO-OP.
-    fn hypothesis_token_count(&self, _hypothesis: &str) -> anyhow::Result<usize> {
-        Ok(0)
-    }
+    /// Required: `OnnxNliVerifier` 는 real tokenizer 로 *trait impl 블록
+    /// 안에서* 구현해야 함 — inherent method 는 vtable 미등록 → trait
+    /// dispatch 시 호출 안 됨 → production silent NO-OP.
+    fn hypothesis_token_count(&self, hypothesis: &str) -> anyhow::Result<usize>;
 }
 
 /// Numerically stable 3-way softmax (subtract max for log-sum-exp safety).
diff --git a/crates/kebab-rag/tests/common/mod.rs b/crates/kebab-rag/tests/common/mod.rs
index cfb92f2..c318098 100644
--- a/crates/kebab-rag/tests/common/mod.rs
+++ b/crates/kebab-rag/tests/common/mod.rs
@@ -454,6 +454,12 @@ impl NliVerifier for MockNliVerifier {
             MockMode::Err(e) => anyhow::bail!("{e}"),
         }
     }
+
+    // Mock doesn't model tokenization; preserves the old trait default
+    // (Ok(0)) so the char-budget retry loop passes through immediately.
+    fn hypothesis_token_count(&self, _hypothesis: &str) -> anyhow::Result<usize> {
+        Ok(0)
+    }
 }
 
 /// S3 follow-up (2026-05-26): closure type aliases for `SpyNliVerifier`
diff --git a/crates/kebab-search/src/hybrid.rs b/crates/kebab-search/src/hybrid.rs
index 8dcf622..581d7be 100644
--- a/crates/kebab-search/src/hybrid.rs
+++ b/crates/kebab-search/src/hybrid.rs
@@ -43,17 +43,6 @@ const HYBRID_FANOUT_MULTIPLIER: usize = 2;
 /// Default `k` when `SearchQuery::k == 0`. Mirrors §6.4 default_k=10.
 const DEFAULT_K: usize = 10;
 
-/// Fusion algorithm. Today only Reciprocal Rank Fusion is supported;
-/// listing as an enum so future score-calibration policies (P+) can
-/// land without an API break.
-#[derive(Clone, Copy, Debug)]
-pub enum FusionPolicy {
-    /// Reciprocal Rank Fusion. `k_rrf` is the standard rank-bias
-    /// hyperparameter (§6.4); larger values flatten the rank-bias
-    /// curve, smaller values privilege top-of-list hits.
-    Rrf { k_rrf: u32 },
-}
-
 /// Hybrid retriever composing a lexical and a vector retriever.
 ///
 /// For chunks that appear in both retrievers, the lexical-side hit
@@ -66,7 +55,7 @@ pub enum FusionPolicy {
 pub struct HybridRetriever {
     lexical: Arc<dyn Retriever>,
     vector: Arc<dyn Retriever>,
-    fusion: FusionPolicy,
+    k_rrf: u32,
     /// Default `k` for queries that arrive with `k == 0`. Pulled from
     /// `config.search.default_k` at construction.
     default_k: usize,
@@ -81,7 +70,7 @@ impl HybridRetriever {
         lexical: Arc<dyn Retriever>,
         vector: Arc<dyn Retriever>,
     ) -> Self {
-        let fusion = parse_fusion(&search.hybrid_fusion, search.rrf_k);
+        let k_rrf = parse_fusion(&search.hybrid_fusion, search.rrf_k);
         let default_k = if search.default_k == 0 {
             DEFAULT_K
         } else {
@@ -104,7 +93,7 @@ impl HybridRetriever {
         Self {
             lexical,
             vector,
-            fusion,
+            k_rrf,
             default_k,
         }
     }
@@ -114,13 +103,13 @@ impl HybridRetriever {
     pub fn with_policy(
         lexical: Arc<dyn Retriever>,
         vector: Arc<dyn Retriever>,
-        fusion: FusionPolicy,
+        k_rrf: u32,
         default_k: usize,
     ) -> Self {
         Self {
             lexical,
             vector,
-            fusion,
+            k_rrf,
             default_k: if default_k == 0 { DEFAULT_K } else { default_k },
         }
     }
@@ -219,7 +208,7 @@ impl HybridRetriever {
         // the same positive constant), so the sort + tiebreak path is
         // unchanged. Wire schema label `fusion_score` keeps its slot in
         // `RetrievalDetail`; only the magnitude shifts.
-        let FusionPolicy::Rrf { k_rrf } = self.fusion;
+        let k_rrf = self.k_rrf;
         let k_rrf_f = f64::from(k_rrf);
         // Both retrievers can contribute, so the per-mode RRF max is
         // 2 / (k_rrf + 1). Even when a chunk lands in only one mode, we
@@ -412,20 +401,20 @@ impl HybridRetriever {
     }
 }
 
-/// Parse the `hybrid_fusion` config string into a [`FusionPolicy`].
+/// Parse the `hybrid_fusion` config string into an RRF `k_rrf`.
 /// Today only `"rrf"` is recognised; anything else falls back to RRF
 /// with a warn log so misconfiguration is visible but not fatal.
-fn parse_fusion(name: &str, k_rrf: u32) -> FusionPolicy {
+fn parse_fusion(name: &str, k_rrf: u32) -> u32 {
     let k = if k_rrf == 0 { DEFAULT_K_RRF } else { k_rrf };
     match name {
-        "rrf" => FusionPolicy::Rrf { k_rrf: k },
+        "rrf" => k,
         other => {
             tracing::warn!(
                 target: "kebab-search",
                 policy = other,
                 "kb-search hybrid: unknown fusion policy; falling back to RRF"
             );
-            FusionPolicy::Rrf { k_rrf: k }
+            k
         }
     }
 }
@@ -520,8 +509,8 @@ mod tests {
         }
     }
 
-    fn rrf_policy(k_rrf: u32) -> FusionPolicy {
-        FusionPolicy::Rrf { k_rrf }
+    fn rrf_policy(k_rrf: u32) -> u32 {
+        k_rrf
     }
 
     fn make_query(mode: SearchMode, k: usize) -> SearchQuery {
@@ -743,14 +732,13 @@ mod tests {
 
     #[test]
     fn parse_fusion_falls_back_to_rrf_on_unknown() {
-        let p = parse_fusion("nonsense", 60);
-        let FusionPolicy::Rrf { k_rrf } = p;
+        let k_rrf = parse_fusion("nonsense", 60);
         assert_eq!(k_rrf, 60);
     }
 
     #[test]
     fn parse_fusion_zero_k_falls_back_to_default() {
-        let FusionPolicy::Rrf { k_rrf } = parse_fusion("rrf", 0);
+        let k_rrf = parse_fusion("rrf", 0);
         assert_eq!(k_rrf, DEFAULT_K_RRF);
     }
 
@@ -838,12 +826,7 @@ mod tests {
                 mk_hit(2, "c3", 0.6, SearchMode::Vector),
             ],
         });
-        let hybrid = HybridRetriever::with_policy(
-            lex.clone(),
-            vec_r.clone(),
-            FusionPolicy::Rrf { k_rrf: 60 },
-            2,
-        );
+        let hybrid = HybridRetriever::with_policy(lex.clone(), vec_r.clone(), 60, 2);
         let q = SearchQuery {
             text: "x".into(),
             mode: SearchMode::Hybrid,
@@ -873,7 +856,7 @@ mod tests {
         }
         let lex = Arc::new(EmptyR);
         let vec_r = Arc::new(EmptyR);
-        let hybrid = HybridRetriever::with_policy(lex, vec_r, FusionPolicy::Rrf { k_rrf: 60 }, 2);
+        let hybrid = HybridRetriever::with_policy(lex, vec_r, 60, 2);
         let q = SearchQuery {
             text: "x".into(),
             mode: SearchMode::Lexical,
@@ -908,7 +891,7 @@ mod tests {
         let vec_r = Arc::new(Stub {
             hits: vec![mk_hit("c1", 1, SearchMode::Vector, 0.8)],
         });
-        let hybrid = HybridRetriever::with_policy(lex, vec_r, FusionPolicy::Rrf { k_rrf: 60 }, 2);
+        let hybrid = HybridRetriever::with_policy(lex, vec_r, 60, 2);
         let q = SearchQuery {
             text: "x".into(),
             mode: SearchMode::Hybrid,
@@ -944,7 +927,7 @@ mod tests {
             hits: vec![lex_hit],
         });
         let vec_r = Arc::new(Stub { hits: vec![] });
-        let hybrid = HybridRetriever::with_policy(lex, vec_r, FusionPolicy::Rrf { k_rrf: 60 }, 2);
+        let hybrid = HybridRetriever::with_policy(lex, vec_r, 60, 2);
         let q = SearchQuery {
             text: "x".into(),
             mode: SearchMode::Lexical,
diff --git a/crates/kebab-search/src/lib.rs b/crates/kebab-search/src/lib.rs
index fef87f3..82da806 100644
--- a/crates/kebab-search/src/lib.rs
+++ b/crates/kebab-search/src/lib.rs
@@ -6,7 +6,7 @@
 //!   `kb-store-vector::LanceVectorStore`) and a `dyn Embedder`,
 //!   hydrating SQLite metadata for full `SearchHit`s.
 //! - [`HybridRetriever`] (P3-4): composes lexical + vector retrievers,
-//!   dispatches by `SearchMode`, fuses Hybrid via [`FusionPolicy::Rrf`].
+//!   dispatches by `SearchMode`, fuses Hybrid via Reciprocal Rank Fusion.
 //!
 //! Allowed deps per the P2-2 + P3-4 task specs: `kb-core`, `kb-config`,
 //! `kb-store-sqlite`, `kb-store-vector`, `kb-embed` (trait re-export
@@ -22,6 +22,6 @@ mod lexical;
 mod trace;
 mod vector;
 
-pub use hybrid::{FusionPolicy, HybridRetriever};
+pub use hybrid::HybridRetriever;
 pub use lexical::LexicalRetriever;
 pub use vector::VectorRetriever;
diff --git a/crates/kebab-search/tests/hybrid.rs b/crates/kebab-search/tests/hybrid.rs
index c34d992..3e5b63a 100644
--- a/crates/kebab-search/tests/hybrid.rs
+++ b/crates/kebab-search/tests/hybrid.rs
@@ -15,14 +15,14 @@ use common::{
     HybridEnv, TEST_LEX_INDEX_VERSION, TEST_VEC_INDEX_VERSION, id32, require_avx_or_panic,
 };
 use kebab_core::{MediaType, Retriever, SearchFilters, SearchHit, SearchMode, SearchQuery};
-use kebab_search::{FusionPolicy, HybridRetriever};
+use kebab_search::HybridRetriever;
 use rusqlite::params;
 use serde_json::json;
 
 fn build_hybrid(env: &HybridEnv) -> HybridRetriever {
     let lex: Arc<dyn Retriever> = Arc::new(env.lexical_retriever());
     let vec: Arc<dyn Retriever> = Arc::new(env.vector_retriever());
-    HybridRetriever::with_policy(lex, vec, FusionPolicy::Rrf { k_rrf: 60 }, 5)
+    HybridRetriever::with_policy(lex, vec, 60, 5)
 }
 
 /// Seed a tiny corpus that lets us prove hybrid recall ≥ each side
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 9ef88cb..1e08557 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -25,7 +25,7 @@ Cargo workspace, 함수 호출 기반 모듈러 모놀리스. UI binary (`kebab-
 | Image caption | Ollama vision LM, runtime gate `image.caption.enabled` (default OFF) |
 | RAG groundedness 검증 | `kebab-nli` 의 mDeBERTa-v3 XNLI 가 `(packed_chunks, generated_answer)` entailment 검사 (fb-41). `[rag] nli_threshold > 0` (default 0 = disabled, production 권장 0.5) 일 때 활성 — 미달 시 `refusal_reason = nli_verification_failed` (LLM self-judge ceiling 보완). 첫 호출 시 ~280 MB ONNX 자동 다운로드 |
 | PDF parser | `lopdf` per-page 텍스트 + scanned-page image extract (`page_image::extract_dctdecode_page_image`, v0.20.0). `chunker_version = "pdf-page-v1"` 하드코딩 (HOTFIXES P7-3). `parser_version = "pdf-text-v1"` 보존 (v0.20 OCR 후에도) — provenance event 로 OCR 사용 차별화. force-reingest 가 v0.19 indexed scanned PDF 의 재처리에 필요. |
-| code parser | `tree-sitter` + `tree-sitter-rust` / `tree-sitter-python` / `tree-sitter-typescript` / `tree-sitter-javascript` / `tree-sitter-go` / `tree-sitter-java` / `tree-sitter-kotlin-ng` — **parser-side** (`kebab-parse-code`), chunker-side 아님 (design §6.3). chunker versions: Rust = `code-rust-ast-v1`, Python = `code-python-ast-v1`, TypeScript = `code-ts-ast-v1`, JavaScript = `code-js-ast-v1`, Go = `code-go-ast-v1`, Java = `code-java-ast-v1`, Kotlin = `code-kotlin-ast-v1`. `ast_chunk_max_lines = 200` 상수 고정 (HOTFIXES 2026-05-19 — Chunker trait 이 per-medium config 미노출). Kotlin grammar 은 `tree-sitter-kotlin-ng` 사용 — bare `tree-sitter-kotlin` 은 tree-sitter 0.21–0.23 에 고착되어 있어 사용 불가. **Tier 2 (p10-2)**: YAML/k8s → `serde_yaml` + `k8s-manifest-resource-v1` (apiVersion+kind per resource), Dockerfile → `dockerfile-file-v1` (whole-file), Cargo.toml/go.mod/.json/.xml/.groovy → `manifest-file-v1` (whole-file). Tier 2 chunkers live in `kebab-chunk`; no tree-sitter grammar needed (structure from file type, not AST). **Tier 3 (p10-3)**: shell scripts (`.sh`/`.bash`/`.zsh`) direct → `code-text-paragraph-v1` (blank-line paragraph segmentation + 80-line / 20-overlap line-window for oversize). Same chunker also serves as fallback when Tier 1/2 emit 0 chunks or Err — non-k8s YAML / invalid YAML / AST extractor failures all picked up. symbol = None; lang preserved from input doc. **Tier 1 family complete (p10-1D)**: C (`tree-sitter-c`, `code-c-ast-v1`, `.c`/`.h`) + C++ (`tree-sitter-cpp`, `code-cpp-ast-v1`, `.cpp`/`.cc`/`.cxx`/`.hpp`/`.hh`/`.hxx`). C symbol = function name only; C++ symbol = `namespace::Class::method` (recursive nesting). `.h` 가 C++ syntax 만나면 tree-sitter-c parse 실패 → Tier 3 fallback. |
+| code parser | `tree-sitter` + `tree-sitter-rust` / `tree-sitter-python` / `tree-sitter-typescript` / `tree-sitter-javascript` / `tree-sitter-go` / `tree-sitter-java` / `tree-sitter-kotlin-ng` — **parser-side** (`kebab-parse-code`), chunker-side 아님 (design §6.3). chunker versions: Rust = `code-rust-ast-v1`, Python = `code-python-ast-v1`, TypeScript = `code-ts-ast-v1`, JavaScript = `code-js-ast-v1`, Go = `code-go-ast-v1`, Java = `code-java-ast-v1`, Kotlin = `code-kotlin-ast-v1`. `ast_chunk_max_lines = 200` 상수 고정 (HOTFIXES 2026-05-19 — Chunker trait 이 per-medium config 미노출). Kotlin grammar 은 `tree-sitter-kotlin-ng` 사용 — bare `tree-sitter-kotlin` 은 tree-sitter 0.21–0.23 에 고착되어 있어 사용 불가. **Tier 2 (p10-2)**: YAML/k8s → `serde_yaml_ng` + `k8s-manifest-resource-v1` (apiVersion+kind per resource), Dockerfile → `dockerfile-file-v1` (whole-file), Cargo.toml/go.mod/.json/.xml/.groovy → `manifest-file-v1` (whole-file). Tier 2 chunkers live in `kebab-chunk`; no tree-sitter grammar needed (structure from file type, not AST). **Tier 3 (p10-3)**: shell scripts (`.sh`/`.bash`/`.zsh`) direct → `code-text-paragraph-v1` (blank-line paragraph segmentation + 80-line / 20-overlap line-window for oversize). Same chunker also serves as fallback when Tier 1/2 emit 0 chunks or Err — non-k8s YAML / invalid YAML / AST extractor failures all picked up. symbol = None; lang preserved from input doc. **Tier 1 family complete (p10-1D)**: C (`tree-sitter-c`, `code-c-ast-v1`, `.c`/`.h`) + C++ (`tree-sitter-cpp`, `code-cpp-ast-v1`, `.cpp`/`.cc`/`.cxx`/`.hpp`/`.hh`/`.hxx`). C symbol = function name only; C++ symbol = `namespace::Class::method` (recursive nesting). `.h` 가 C++ syntax 만나면 tree-sitter-c parse 실패 → Tier 3 fallback. |
 | symbol path 형식 | workspace path → module path: Python = dotted prefix (`kebab_eval.metrics.compute_mrr`), TypeScript/JavaScript = slash-style prefix (`src/Foo.Foo.search`), Go = `package.Func` / `package.(*Receiver).Method`, Java/Kotlin = `com.foo.Foo.bar` (패키지+클래스+메서드/필드), C = 함수명, C++ = `namespace::Class::method`. Rust 1A-2 는 file-scope nesting 만 (workspace prefix 없음, 비일관 수용 — HOTFIXES 2026-05-20). code chunk 은 `citation.kind = "code"` + `citation.lang` + `symbol` + line range, SearchHit 에 `code_lang` + `repo`(`.git` walk-up 디렉토리명) backfill. |
 | Desktop | Tauri 2 + `pdfjs-dist` (native PDF render backend 금지) — P9-5 |
 | citation 형식 | URI fragment (`path#L12-L34` / `path#p=12` / `path#xywh=0,0,100,50`, W3C Media Fragments) |
diff --git a/docs/components/eval/README.md b/docs/components/eval/README.md
index ec6a58d..0593eb5 100644
--- a/docs/components/eval/README.md
+++ b/docs/components/eval/README.md
@@ -105,7 +105,7 @@ flowchart LR
 ## 주요 type / trait / 함수
 
 **Loader** (`kebab-eval::loader`):
-- `load_golden_set(path: &Path) -> Result<Vec<GoldenQuery>>` — `serde_yaml` 위 YAML 파싱.
+- `load_golden_set(path: &Path) -> Result<Vec<GoldenQuery>>` — `serde_yaml_ng` 위 YAML 파싱.
 - `GoldenQuery { id, query, mode, k, must_contain, expected_doc_ids, ask }` — fixture 한 entry. `must_contain` 가 case-sensitive substring 검사.
 
 **Runner** (`kebab-eval::runner`):
@@ -133,7 +133,7 @@ flowchart LR
 ## 외부 의존
 
 - crate dep: `kebab-core` + `kebab-config` + `kebab-app` (facade only) + `kebab-store-sqlite` (SQLite 직접 read/write — `eval_runs` / `eval_query_results` 측). retrieval / embedding / LLM crate 직접 import **금지**.
-- 외부 lib: `serde_yaml` (golden YAML), `serde_json`, `uuid` (v7), `time`, `tracing`, `anyhow`.
+- 외부 lib: `serde_yaml_ng` (golden YAML), `serde_json`, `uuid` (v7), `time`, `tracing`, `anyhow`.
 - 외부 서비스: 없음 (facade 가 가져옴).
 
 ## 핵심 결정
diff --git a/docs/components/parse/README.md b/docs/components/parse/README.md
index f772a55..3e4c654 100644
--- a/docs/components/parse/README.md
+++ b/docs/components/parse/README.md
@@ -114,7 +114,7 @@ flowchart LR
 
 - crate dep:
   - 모든 parser → `kebab-core` (`Extractor` trait, `Block`, `Metadata`, `id_for_*`).
-  - `kebab-parse-md` → `kebab-parse-types` (`ParsedBlock`/`ParsedPayload`/`Warning`), `pulldown-cmark`, `serde_yaml`.
+  - `kebab-parse-md` → `kebab-parse-types` (`ParsedBlock`/`ParsedPayload`/`Warning`), `pulldown-cmark`, `serde_yaml_ng`.
   - `kebab-parse-pdf` → `lopdf`.
   - `kebab-parse-image` → `image` (decode), `kamadak-exif` (EXIF), `kebab-core::LanguageModel` (caption).
 - 외부 서비스:
diff --git a/docs/components/search/README.md b/docs/components/search/README.md
index 59d9b62..990f0a4 100644
--- a/docs/components/search/README.md
+++ b/docs/components/search/README.md
@@ -30,16 +30,12 @@ classDiagram
     }
     class HybridRetriever {
         +new(cfg, lexical, vector) Self
-        +with_policy(lex, vec, FusionPolicy, k)
+        +with_policy(lex, vec, k_rrf, default_k)
         -lexical: Arc~dyn Retriever~
         -vector: Arc~dyn Retriever~
-        -fusion: FusionPolicy
+        -k_rrf: u32
         -default_k: usize
     }
-    class FusionPolicy {
-        <<enum>>
-        Rrf{k_rrf}
-    }
     class SearchMode {
         <<enum>>
         Lexical
@@ -51,7 +47,6 @@ classDiagram
     Retriever <|.. HybridRetriever
     HybridRetriever --> LexicalRetriever
     HybridRetriever --> VectorRetriever
-    HybridRetriever ..> FusionPolicy
     HybridRetriever ..> SearchMode : dispatch
 ```
 
@@ -95,7 +90,7 @@ flowchart LR
 
 **HybridRetriever** (`kebab-search::hybrid`):
 - `HybridRetriever::new(&Config, Arc<dyn Retriever> lex, Arc<dyn Retriever> vec) -> Self` — `config.search.hybrid_fusion` (`"rrf"`) + `config.search.rrf_k` 읽음. 두 retriever 의 `index_version` 가 다르면 `tracing::warn`.
-- `FusionPolicy::Rrf { k_rrf }` — default 60. `with_policy` 헬퍼로 explicit 지정 가능.
+- `k_rrf: u32` — default 60. `with_policy` 헬퍼로 explicit 지정 가능.
 - 상수: `DEFAULT_K = 10` (query.k == 0 fallback), `DEFAULT_K_RRF = 60`, `HYBRID_FANOUT_MULTIPLIER = 2`.
 - merge rule: 양측 등장 chunk 의 `snippet` / `citation` / `heading_path` 는 lexical 측에서 가져옴 (FTS5 highlight 가 vector 의 truncated text 보다 user-relevant).