diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0e9c21e..575e567 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -184,6 +184,47 @@ callers).
   globally — noisy on parser mappers and orchestrator use-cases where early-return
   validation is essential complexity. Ignore `PLW0603` for the documented memory
   singleton (`infrastructure/persistence/context.py`).
+- **Release-knowledge DDD purification** (`refactor/domain-release-knowledge`):
+  the last domain → infrastructure leak (`domain/release/value_objects.py`
+  loading YAML at import-time) is gone. Achieved via:
+  - **`ReleaseKnowledge` Protocol port** at
+    `alfred/domain/release/ports/knowledge.py` declares the read-only query
+    surface release parsing needs (token sets for resolutions, sources, codecs,
+    languages, hdr extras; structured dicts for audio, video_meta, editions,
+    media_type_tokens; separators list; file-extension sets used by
+    application/infra callers; `sanitize_for_fs(text)` method).
+  - **`YamlReleaseKnowledge` adapter** at
+    `alfred/infrastructure/knowledge/release_kb.py` loads every YAML constant
+    once at construction. Builds an immutable `str.maketrans` translation
+    table for filesystem sanitization.
+  - **`parse_release(name, kb)`** takes the knowledge as an explicit
+    parameter — no more module-level YAML loading inside the domain. Every
+    internal helper (`_tokenize`, `_extract_tech`, `_extract_languages`,
+    `_extract_audio`, `_extract_video_meta`, `_extract_edition`,
+    `_extract_title`, `_infer_media_type`, `_is_well_formed`) takes `kb`.
+  - **`ParsedRelease` Option B**: sanitization happens once at parse time
+    and is stored on a new `title_sanitized: str` field. Builder methods
+    (`show_folder_name`, `season_folder_name`, `episode_filename`,
+    `movie_folder_name`, `movie_filename`) are now pure — they accept
+    already-sanitized `tmdb_title_safe` / `tmdb_episode_title_safe`
+    arguments. Callers at the use-case boundary sanitize TMDB strings
+    via `kb.sanitize_for_fs(...)` before passing them in.
+  - **All domain-knowledge constants removed from `value_objects.py`**:
+    `_RESOLUTIONS`, `_SOURCES`, `_CODECS`, `_AUDIO`, `_VIDEO_META`,
+    `_EDITIONS`, `_HDR_EXTRA`, `_MEDIA_TYPE_TOKENS`, `_LANGUAGE_TOKENS`,
+    `_FORBIDDEN_CHARS`, `_VIDEO_EXTENSIONS`, `_NON_VIDEO_EXTENSIONS`,
+    `_SUBTITLE_EXTENSIONS`, `_METADATA_EXTENSIONS`, `_WIN_FORBIDDEN_TABLE`,
+    and the `_sanitize_for_fs` helper. The domain module is now pure.
+  - **Application-layer KB singleton**: `resolve_destination.py` instantiates
+    a module-level `_KB: ReleaseKnowledge = YamlReleaseKnowledge()` and
+    threads it through every `parse_release(...)` call. The local
+    `_sanitize` helper and `_WIN_FORBIDDEN` regex were dropped in favor of
+    `_KB.sanitize_for_fs(...)`.
+  - **`detect_media_type(parsed, source_path, kb)` and
+    `find_video_file(path, kb)`** now take the knowledge explicitly
+    instead of importing `_*_EXTENSIONS` constants from the domain.
+    `agent/tools/filesystem.py::analyze_release` imports the application
+    KB singleton and passes it through.
 
 ---
 
diff --git a/alfred/agent/tools/filesystem.py b/alfred/agent/tools/filesystem.py
index 9abadec..afb156e 100644
--- a/alfred/agent/tools/filesystem.py
+++ b/alfred/agent/tools/filesystem.py
@@ -190,15 +190,16 @@ def set_path_for_folder(folder_name: str, path_value: str) -> dict[str, Any]:
 
 def analyze_release(release_name: str, source_path: str) -> dict[str, Any]:
     """Thin tool wrapper — semantics live in alfred/agent/tools/specs/analyze_release.yaml."""
+    from alfred.application.filesystem.resolve_destination import _KB  # noqa: PLC0415
     from alfred.domain.release.services import parse_release  # noqa: PLC0415
 
     path = Path(source_path)
-    parsed = parse_release(release_name)
-    parsed.media_type = detect_media_type(parsed, path)
+    parsed = parse_release(release_name, _KB)
+    parsed.media_type = detect_media_type(parsed, path, _KB)
 
     probe_used = False
     if parsed.media_type not in ("unknown", "other"):
-        video_file = find_video_file(path)
+        video_file = find_video_file(path, _KB)
         if video_file:
             media_info = probe(video_file)
             if media_info:
diff --git a/alfred/application/filesystem/detect_media_type.py b/alfred/application/filesystem/detect_media_type.py
index 10c584a..1fbef84 100644
--- a/alfred/application/filesystem/detect_media_type.py
+++ b/alfred/application/filesystem/detect_media_type.py
@@ -19,15 +19,13 @@ from __future__ import annotations
 
 from pathlib import Path
 
-from alfred.domain.release.value_objects import (
-    _METADATA_EXTENSIONS,
-    _NON_VIDEO_EXTENSIONS,
-    _VIDEO_EXTENSIONS,
-    ParsedRelease,
-)
+from alfred.domain.release.ports import ReleaseKnowledge
+from alfred.domain.release.value_objects import ParsedRelease
 
 
-def detect_media_type(parsed: ParsedRelease, source_path: Path) -> str:
+def detect_media_type(
+    parsed: ParsedRelease, source_path: Path, kb: ReleaseKnowledge
+) -> str:
     """
     Return a refined media_type string for the given source_path.
 
@@ -37,10 +35,10 @@ def detect_media_type(parsed: ParsedRelease, source_path: Path) -> str:
     extensions = _collect_extensions(source_path)
     # Metadata extensions (.nfo, .srt, …) are always present alongside releases
     # and must not influence the type decision.
-    conclusive = extensions - _METADATA_EXTENSIONS
+    conclusive = extensions - kb.metadata_extensions
 
-    has_video = bool(conclusive & _VIDEO_EXTENSIONS)
-    has_non_video = bool(conclusive & _NON_VIDEO_EXTENSIONS)
+    has_video = bool(conclusive & kb.video_extensions)
+    has_non_video = bool(conclusive & kb.non_video_extensions)
 
     if has_video and has_non_video:
         return "unknown"
diff --git a/alfred/application/filesystem/resolve_destination.py b/alfred/application/filesystem/resolve_destination.py
index 2a5aeb3..5fc5f44 100644
--- a/alfred/application/filesystem/resolve_destination.py
+++ b/alfred/application/filesystem/resolve_destination.py
@@ -8,34 +8,39 @@ Four distinct use cases, one per release type:
 - resolve_series_destination    : complete series multi-season pack (folder move)
 
 Each returns a dedicated DTO with only the fields that make sense for that type.
+
+These use cases follow Option B of the snapshot-VO design: ``ParsedRelease``
+arrives with ``title_sanitized`` already computed, and TMDB-supplied strings
+are sanitized **at the use-case boundary** (here) before being passed into
+``ParsedRelease`` builder methods. The builders themselves perform no I/O and
+no sanitization.
 """
 
 from __future__ import annotations
 
 import logging
-import re
 from dataclasses import dataclass
 from pathlib import Path
 
 from alfred.domain.release import parse_release
+from alfred.domain.release.ports import ReleaseKnowledge
+from alfred.infrastructure.knowledge.release_kb import YamlReleaseKnowledge
 from alfred.infrastructure.persistence import get_memory
 
 logger = logging.getLogger(__name__)
 
-_WIN_FORBIDDEN = re.compile(r'[?:*"<>|\\]')
-
-
-def _sanitize(text: str) -> str:
-    return _WIN_FORBIDDEN.sub("", text)
+# Single module-level knowledge instance. YAML is loaded once at first import.
+# Tests that need a custom KB can monkeypatch this attribute.
+_KB: ReleaseKnowledge = YamlReleaseKnowledge()
 
 
 def _find_existing_tvshow_folders(
-    tv_root: Path, tmdb_title: str, tmdb_year: int
+    tv_root: Path, tmdb_title_safe: str, tmdb_year: int
 ) -> list[str]:
     """Return folder names in tv_root that match title + year prefix."""
     if not tv_root.exists():
         return []
-    clean_title = _sanitize(tmdb_title).replace(" ", ".")
+    clean_title = tmdb_title_safe.replace(" ", ".")
     prefix = f"{clean_title}.{tmdb_year}".lower()
     return sorted(
         entry.name
@@ -66,6 +71,7 @@ class _Clarification:
 def _resolve_series_folder(
     tv_root: Path,
     tmdb_title: str,
+    tmdb_title_safe: str,
     tmdb_year: int,
     computed_name: str,
     confirmed_folder: str | None,
@@ -80,7 +86,7 @@ def _resolve_series_folder(
     if confirmed_folder:
         return confirmed_folder, not (tv_root / confirmed_folder).exists()
 
-    existing = _find_existing_tvshow_folders(tv_root, tmdb_title, tmdb_year)
+    existing = _find_existing_tvshow_folders(tv_root, tmdb_title_safe, tmdb_year)
 
     if not existing:
         return computed_name, True
@@ -246,11 +252,12 @@ def resolve_season_destination(
             message="TV show library path is not configured.",
         )
 
-    parsed = parse_release(release_name)
-    computed_name = _sanitize(parsed.show_folder_name(tmdb_title, tmdb_year))
+    parsed = parse_release(release_name, _KB)
+    tmdb_title_safe = _KB.sanitize_for_fs(tmdb_title)
+    computed_name = parsed.show_folder_name(tmdb_title_safe, tmdb_year)
 
     resolved = _resolve_series_folder(
-        tv_root, tmdb_title, tmdb_year, computed_name, confirmed_folder
+        tv_root, tmdb_title, tmdb_title_safe, tmdb_year, computed_name, confirmed_folder
     )
     if isinstance(resolved, _Clarification):
         return ResolvedSeasonDestination(
@@ -295,12 +302,16 @@ def resolve_episode_destination(
             message="TV show library path is not configured.",
         )
 
-    parsed = parse_release(release_name)
+    parsed = parse_release(release_name, _KB)
     ext = Path(source_file).suffix
-    computed_name = _sanitize(parsed.show_folder_name(tmdb_title, tmdb_year))
+    tmdb_title_safe = _KB.sanitize_for_fs(tmdb_title)
+    tmdb_episode_title_safe = (
+        _KB.sanitize_for_fs(tmdb_episode_title) if tmdb_episode_title else None
+    )
+    computed_name = parsed.show_folder_name(tmdb_title_safe, tmdb_year)
 
     resolved = _resolve_series_folder(
-        tv_root, tmdb_title, tmdb_year, computed_name, confirmed_folder
+        tv_root, tmdb_title, tmdb_title_safe, tmdb_year, computed_name, confirmed_folder
     )
     if isinstance(resolved, _Clarification):
         return ResolvedEpisodeDestination(
@@ -311,7 +322,7 @@ def resolve_episode_destination(
 
     series_folder_name, is_new = resolved
     season_folder_name = parsed.season_folder_name()
-    filename = _sanitize(parsed.episode_filename(tmdb_episode_title, ext))
+    filename = parsed.episode_filename(tmdb_episode_title_safe, ext)
 
     series_path = tv_root / series_folder_name
     season_path = series_path / season_folder_name
@@ -349,11 +360,12 @@ def resolve_movie_destination(
             message="Movie library path is not configured.",
         )
 
-    parsed = parse_release(release_name)
+    parsed = parse_release(release_name, _KB)
     ext = Path(source_file).suffix
+    tmdb_title_safe = _KB.sanitize_for_fs(tmdb_title)
 
-    folder_name = _sanitize(parsed.movie_folder_name(tmdb_title, tmdb_year))
-    filename = _sanitize(parsed.movie_filename(tmdb_title, tmdb_year, ext))
+    folder_name = parsed.movie_folder_name(tmdb_title_safe, tmdb_year)
+    filename = parsed.movie_filename(tmdb_title_safe, tmdb_year, ext)
 
     folder_path = Path(movies_root) / folder_name
     file_path = folder_path / filename
@@ -387,11 +399,12 @@ def resolve_series_destination(
             message="TV show library path is not configured.",
         )
 
-    parsed = parse_release(release_name)
-    computed_name = _sanitize(parsed.show_folder_name(tmdb_title, tmdb_year))
+    parsed = parse_release(release_name, _KB)
+    tmdb_title_safe = _KB.sanitize_for_fs(tmdb_title)
+    computed_name = parsed.show_folder_name(tmdb_title_safe, tmdb_year)
 
     resolved = _resolve_series_folder(
-        tv_root, tmdb_title, tmdb_year, computed_name, confirmed_folder
+        tv_root, tmdb_title, tmdb_title_safe, tmdb_year, computed_name, confirmed_folder
     )
     if isinstance(resolved, _Clarification):
         return ResolvedSeriesDestination(
diff --git a/alfred/domain/release/ports/__init__.py b/alfred/domain/release/ports/__init__.py
new file mode 100644
index 0000000..b4ae2ec
--- /dev/null
+++ b/alfred/domain/release/ports/__init__.py
@@ -0,0 +1,10 @@
+"""Domain ports for the release domain.
+
+Protocol-based abstractions that decouple ``parse_release`` and
+``ParsedRelease`` from any concrete knowledge-base loader. The
+infrastructure layer provides the adapter that satisfies this contract.
+"""
+
+from .knowledge import ReleaseKnowledge
+
+__all__ = ["ReleaseKnowledge"]
diff --git a/alfred/domain/release/ports/knowledge.py b/alfred/domain/release/ports/knowledge.py
new file mode 100644
index 0000000..272e7ef
--- /dev/null
+++ b/alfred/domain/release/ports/knowledge.py
@@ -0,0 +1,52 @@
+"""ReleaseKnowledge port — the read-only query surface that
+``parse_release`` and ``ParsedRelease`` need from the release knowledge
+base, expressed as a structural Protocol so the domain never imports any
+concrete loader.
+
+The concrete YAML-backed implementation lives in
+``alfred/infrastructure/knowledge/release_kb.py``. Tests can supply any
+object that satisfies this shape (e.g. a simple dataclass).
+"""
+
+from __future__ import annotations
+
+from typing import Protocol
+
+
+class ReleaseKnowledge(Protocol):
+    """Read-only snapshot of release-name parsing knowledge."""
+
+    # --- Token sets used by the tokenizer / matchers ---
+
+    resolutions: set[str]
+    sources: set[str]
+    codecs: set[str]
+    language_tokens: set[str]
+    forbidden_chars: set[str]
+    hdr_extra: set[str]
+
+    # --- Structured knowledge (loaded from YAML as dicts) ---
+
+    audio: dict
+    video_meta: dict
+    editions: dict
+    media_type_tokens: dict
+
+    # --- Tokenizer separators ---
+
+    separators: list[str]
+
+    # --- File-extension sets (used by application/infra modules that work
+    #     directly with filesystem paths, e.g. media-type detection, video
+    #     lookup). Domain parsing itself doesn't touch these. ---
+
+    video_extensions: set[str]
+    non_video_extensions: set[str]
+    subtitle_extensions: set[str]
+    metadata_extensions: set[str]
+
+    # --- Filesystem sanitization (Option B: pre-sanitize at parse time) ---
+
+    def sanitize_for_fs(self, text: str) -> str:
+        """Strip filesystem-forbidden characters from ``text``."""
+        ...
diff --git a/alfred/domain/release/services.py b/alfred/domain/release/services.py
index 5bfd699..c2b943f 100644
--- a/alfred/domain/release/services.py
+++ b/alfred/domain/release/services.py
@@ -4,31 +4,17 @@ from __future__ import annotations
 
 import re
 
-from alfred.infrastructure.knowledge.release import load_separators
-from .value_objects import (
-    _AUDIO,
-    _CODECS,
-    _EDITIONS,
-    _FORBIDDEN_CHARS,
-    _HDR_EXTRA,
-    _LANGUAGE_TOKENS,
-    _MEDIA_TYPE_TOKENS,
-    _RESOLUTIONS,
-    _SOURCES,
-    _VIDEO_META,
-    MediaTypeToken,
-    ParsedRelease,
-    ParsePath,
-)
+from .ports import ReleaseKnowledge
+from .value_objects import MediaTypeToken, ParsedRelease, ParsePath
 
 
-def _tokenize(name: str) -> list[str]:
+def _tokenize(name: str, kb: ReleaseKnowledge) -> list[str]:
     """Split a release name on the configured separators, dropping empty tokens."""
-    pattern = "[" + re.escape("".join(load_separators())) + "]+"
+    pattern = "[" + re.escape("".join(kb.separators)) + "]+"
     return [t for t in re.split(pattern, name) if t]
 
 
-def parse_release(name: str) -> ParsedRelease:
+def parse_release(name: str, kb: ReleaseKnowledge) -> ParsedRelease:
     """
     Parse a release name and return a ParsedRelease.
 
@@ -48,11 +34,12 @@ def parse_release(name: str) -> ParsedRelease:
     if site_tag is not None:
         parse_path = ParsePath.SANITIZED.value
 
-    if not _is_well_formed(clean):
+    if not _is_well_formed(clean, kb):
         return ParsedRelease(
             raw=name,
             normalised=clean,
             title=clean,
+            title_sanitized=kb.sanitize_for_fs(clean),
             year=None,
             season=None,
             episode=None,
@@ -68,21 +55,22 @@ def parse_release(name: str) -> ParsedRelease:
         )
 
     name = clean
-    tokens = _tokenize(name)
+    tokens = _tokenize(name, kb)
 
     season, episode, episode_end = _extract_season_episode(tokens)
-    quality, source, codec, group, tech_tokens = _extract_tech(tokens)
-    languages, lang_tokens = _extract_languages(tokens)
-    audio_codec, audio_channels, audio_tokens = _extract_audio(tokens)
-    bit_depth, hdr_format, video_tokens = _extract_video_meta(tokens)
-    edition, edition_tokens = _extract_edition(tokens)
+    quality, source, codec, group, tech_tokens = _extract_tech(tokens, kb)
+    languages, lang_tokens = _extract_languages(tokens, kb)
+    audio_codec, audio_channels, audio_tokens = _extract_audio(tokens, kb)
+    bit_depth, hdr_format, video_tokens = _extract_video_meta(tokens, kb)
+    edition, edition_tokens = _extract_edition(tokens, kb)
     title = _extract_title(
         tokens,
         tech_tokens | lang_tokens | audio_tokens | video_tokens | edition_tokens,
+        kb,
     )
     year = _extract_year(tokens, title)
     media_type = _infer_media_type(
-        season, quality, source, codec, year, edition, tokens
+        season, quality, source, codec, year, edition, tokens, kb
     )
 
     tech_parts = [p for p in [quality, source, codec] if p]
@@ -92,6 +80,7 @@ def parse_release(name: str) -> ParsedRelease:
         raw=name,
         normalised=name,
         title=title,
+        title_sanitized=kb.sanitize_for_fs(title),
         year=year,
         season=season,
         episode=episode,
@@ -121,6 +110,7 @@ def _infer_media_type(
     year: int | None,
     edition: str | None,
     tokens: list[str],
+    kb: ReleaseKnowledge,
 ) -> str:
     """
     Infer media_type from token-level evidence only (no filesystem access).
@@ -134,9 +124,9 @@ def _infer_media_type(
     """
     upper_tokens = {t.upper() for t in tokens}
 
-    doc_tokens = {t.upper() for t in _MEDIA_TYPE_TOKENS.get("doc", [])}
-    concert_tokens = {t.upper() for t in _MEDIA_TYPE_TOKENS.get("concert", [])}
-    integrale_tokens = {t.upper() for t in _MEDIA_TYPE_TOKENS.get("integrale", [])}
+    doc_tokens = {t.upper() for t in kb.media_type_tokens.get("doc", [])}
+    concert_tokens = {t.upper() for t in kb.media_type_tokens.get("concert", [])}
+    integrale_tokens = {t.upper() for t in kb.media_type_tokens.get("integrale", [])}
 
     if upper_tokens & doc_tokens:
         return MediaTypeToken.DOCUMENTARY.value
@@ -154,15 +144,15 @@ def _infer_media_type(
     return MediaTypeToken.UNKNOWN.value
 
 
-def _is_well_formed(name: str) -> bool:
+def _is_well_formed(name: str, kb: ReleaseKnowledge) -> bool:
     """Return True if name contains no forbidden characters per scene naming rules.
 
     Characters listed as token separators (spaces, brackets, parens, …) are NOT
     considered malforming — the tokenizer handles them. Only truly broken chars
     like '@', '#', '!', '%' make a name malformed.
     """
-    tokenizable = set(load_separators())
-    return not any(c in name for c in _FORBIDDEN_CHARS if c not in tokenizable)
+    tokenizable = set(kb.separators)
+    return not any(c in name for c in kb.forbidden_chars if c not in tokenizable)
 
 
 def _strip_site_tag(name: str) -> tuple[str, str | None]:
@@ -251,6 +241,7 @@ def _extract_season_episode(
 
 def _extract_tech(
     tokens: list[str],
+    kb: ReleaseKnowledge,
 ) -> tuple[str | None, str | None, str | None, str, set[str]]:
     """
     Extract quality, source, codec, group from tokens.
@@ -270,12 +261,12 @@ def _extract_tech(
     for tok in tokens:
         tl = tok.lower()
 
-        if tl in _RESOLUTIONS:
+        if tl in kb.resolutions:
             quality = tok
             tech_tokens.add(tok)
             continue
 
-        if tl in _SOURCES:
+        if tl in kb.sources:
             source = tok
             tech_tokens.add(tok)
             continue
@@ -283,18 +274,18 @@ def _extract_tech(
         if "-" in tok:
             parts = tok.rsplit("-", 1)
             # codec-GROUP (highest priority for group)
-            if parts[0].lower() in _CODECS:
+            if parts[0].lower() in kb.codecs:
                 codec = parts[0]
                 group = parts[1] if parts[1] else "UNKNOWN"
                 tech_tokens.add(tok)
                 continue
             # source with dash: Web-DL, WEB-DL, etc.
-            if parts[0].lower() in _SOURCES or tok.lower().replace("-", "") in _SOURCES:
+            if parts[0].lower() in kb.sources or tok.lower().replace("-", "") in kb.sources:
                 source = tok
                 tech_tokens.add(tok)
                 continue
 
-        if tl in _CODECS:
+        if tl in kb.codecs:
             codec = tok
             tech_tokens.add(tok)
 
@@ -304,7 +295,7 @@ def _extract_tech(
             if "-" in tok:
                 parts = tok.rsplit("-", 1)
                 tl = tok.lower()
-                if tl in _SOURCES or tok.lower().replace("-", "") in _SOURCES:
+                if tl in kb.sources or tok.lower().replace("-", "") in kb.sources:
                     continue
                 if parts[1]:
                     group = parts[1]
@@ -318,17 +309,20 @@ def _is_year_token(tok: str) -> bool:
     return len(tok) == 4 and tok.isdigit() and 1900 <= int(tok) <= 2099
 
 
-def _extract_title(tokens: list[str], tech_tokens: set[str]) -> str:
+def _extract_title(
+    tokens: list[str], tech_tokens: set[str], kb: ReleaseKnowledge
+) -> str:
     """Extract the title portion: everything before the first season/year/tech token."""
     title_parts = []
+    known_tech = kb.resolutions | kb.sources | kb.codecs
     for tok in tokens:
         if _parse_season_episode(tok) is not None:
             break
         if _is_year_token(tok):
             break
-        if tok in tech_tokens or tok.lower() in _RESOLUTIONS | _SOURCES | _CODECS:
+        if tok in tech_tokens or tok.lower() in known_tech:
             break
-        if "-" in tok and any(p.lower() in _CODECS | _SOURCES for p in tok.split("-")):
+        if "-" in tok and any(p.lower() in kb.codecs | kb.sources for p in tok.split("-")):
             break
         title_parts.append(tok)
 
@@ -376,12 +370,14 @@ def _match_sequences(
 # ---------------------------------------------------------------------------
 
 
-def _extract_languages(tokens: list[str]) -> tuple[list[str], set[str]]:
+def _extract_languages(
+    tokens: list[str], kb: ReleaseKnowledge
+) -> tuple[list[str], set[str]]:
     """Extract language tokens. Returns (languages, matched_token_set)."""
     languages = []
     lang_tokens: set[str] = set()
     for tok in tokens:
-        if tok.upper() in _LANGUAGE_TOKENS:
+        if tok.upper() in kb.language_tokens:
             languages.append(tok.upper())
             lang_tokens.add(tok)
     return languages, lang_tokens
@@ -393,7 +389,7 @@ def _extract_languages(tokens: list[str]) -> tuple[list[str], set[str]]:
 
 
 def _extract_audio(
-    tokens: list[str],
+    tokens: list[str], kb: ReleaseKnowledge,
 ) -> tuple[str | None, str | None, set[str]]:
     """
     Extract audio codec and channel layout.
@@ -405,12 +401,12 @@ def _extract_audio(
     audio_channels: str | None = None
     audio_tokens: set[str] = set()
 
-    known_codecs = {c.upper() for c in _AUDIO.get("codecs", [])}
-    known_channels = set(_AUDIO.get("channels", []))
+    known_codecs = {c.upper() for c in kb.audio.get("codecs", [])}
+    known_channels = set(kb.audio.get("channels", []))
 
     # Try multi-token sequences first
     matched_codec, matched_set = _match_sequences(
-        tokens, _AUDIO.get("sequences", []), "codec"
+        tokens, kb.audio.get("sequences", []), "codec"
     )
     if matched_codec:
         audio_codec = matched_codec
@@ -446,7 +442,7 @@ def _extract_audio(
 
 
 def _extract_video_meta(
-    tokens: list[str],
+    tokens: list[str], kb: ReleaseKnowledge,
 ) -> tuple[str | None, str | None, set[str]]:
     """
     Extract bit depth and HDR format.
@@ -457,12 +453,12 @@ def _extract_video_meta(
     hdr_format: str | None = None
     video_tokens: set[str] = set()
 
-    known_hdr = {h.upper() for h in _VIDEO_META.get("hdr", [])} | _HDR_EXTRA
-    known_depth = {d.lower() for d in _VIDEO_META.get("bit_depth", [])}
+    known_hdr = {h.upper() for h in kb.video_meta.get("hdr", [])} | kb.hdr_extra
+    known_depth = {d.lower() for d in kb.video_meta.get("bit_depth", [])}
 
     # Try HDR sequences first
     matched_hdr, matched_set = _match_sequences(
-        tokens, _VIDEO_META.get("sequences", []), "hdr"
+        tokens, kb.video_meta.get("sequences", []), "hdr"
     )
     if matched_hdr:
         hdr_format = matched_hdr
@@ -486,17 +482,19 @@ def _extract_video_meta(
 # ---------------------------------------------------------------------------
 
 
-def _extract_edition(tokens: list[str]) -> tuple[str | None, set[str]]:
+def _extract_edition(
+    tokens: list[str], kb: ReleaseKnowledge
+) -> tuple[str | None, set[str]]:
     """
     Extract release edition (UNRATED, EXTENDED, DIRECTORS.CUT, …).
 
     Returns (edition, matched_token_set).
     """
-    known_tokens = {t.upper() for t in _EDITIONS.get("tokens", [])}
+    known_tokens = {t.upper() for t in kb.editions.get("tokens", [])}
 
     # Try multi-token sequences first
     matched_edition, matched_set = _match_sequences(
-        tokens, _EDITIONS.get("sequences", []), "edition"
+        tokens, kb.editions.get("sequences", []), "edition"
     )
     if matched_edition:
         return matched_edition, matched_set
diff --git a/alfred/domain/release/value_objects.py b/alfred/domain/release/value_objects.py
index 124a693..87329aa 100644
--- a/alfred/domain/release/value_objects.py
+++ b/alfred/domain/release/value_objects.py
@@ -1,4 +1,17 @@
-"""Release domain — value objects and token sets."""
+"""Release domain — value objects.
+
+This module is **pure**: no I/O, no YAML loading, no knowledge-base
+imports. All knowledge that the parser consumes is injected at runtime
+via the ``ReleaseKnowledge`` port (see ``ports/knowledge.py``).
+
+``ParsedRelease`` follows Option B of the snapshot-VO design: filesystem
+sanitization is performed once at parse time and stored in
+``title_sanitized``. The builder methods (``show_folder_name``,
+``episode_filename``, etc.) are therefore pure string-formatting and do
+**not** need access to any knowledge base — but they require the caller
+to pass already-sanitized TMDB strings. The use case is responsible for
+calling ``kb.sanitize_for_fs(tmdb_title)`` before invoking the builders.
+"""
 
 from __future__ import annotations
 
@@ -6,50 +19,6 @@ from dataclasses import dataclass, field
 from enum import Enum
 
 from ..shared.exceptions import ValidationError
-from alfred.infrastructure.knowledge.release import (
-    load_audio,
-    load_codecs,
-    load_editions,
-    load_forbidden_chars,
-    load_hdr_extra,
-    load_language_tokens,
-    load_media_type_tokens,
-    load_metadata_extensions,
-    load_non_video_extensions,
-    load_resolutions,
-    load_sources,
-    load_sources_extra,
-    load_subtitle_extensions,
-    load_video,
-    load_video_extensions,
-    load_win_forbidden_chars,
-)
-
-# Token sets — loaded once at import time from alfred/knowledge/release/
-_RESOLUTIONS: set[str] = load_resolutions()
-_SOURCES: set[str] = load_sources() | load_sources_extra()
-_CODECS: set[str] = load_codecs()
-_VIDEO_EXTENSIONS: set[str] = load_video_extensions()
-_NON_VIDEO_EXTENSIONS: set[str] = load_non_video_extensions()
-_SUBTITLE_EXTENSIONS: set[str] = load_subtitle_extensions()
-# Both metadata and subtitle extensions are ignored when deciding the media
-# type of a folder — neither is a conclusive signal for movie/tv/other.
-_METADATA_EXTENSIONS: set[str] = load_metadata_extensions() | _SUBTITLE_EXTENSIONS
-_FORBIDDEN_CHARS: set[str] = load_forbidden_chars()
-_LANGUAGE_TOKENS: set[str] = load_language_tokens()
-_AUDIO: dict = load_audio()
-_VIDEO_META: dict = load_video()
-_EDITIONS: dict = load_editions()
-_HDR_EXTRA: set[str] = load_hdr_extra()
-_MEDIA_TYPE_TOKENS: dict = load_media_type_tokens()
-
-# Translation table for stripping Windows-forbidden characters
-_WIN_FORBIDDEN_TABLE = str.maketrans("", "", "".join(load_win_forbidden_chars()))
-
-
-def _sanitize_for_fs(text: str) -> str:
-    """Remove Windows-forbidden characters from a string."""
-    return text.translate(_WIN_FORBIDDEN_TABLE)
 
 
 class MediaTypeToken(str, Enum):
@@ -105,11 +74,17 @@ def _strip_episode_from_normalized(normalized: str) -> str:
 
 @dataclass
 class ParsedRelease:
-    """Structured representation of a parsed release name."""
+    """Structured representation of a parsed release name.
+
+    ``title_sanitized`` carries the filesystem-safe form of ``title`` (computed
+    by the parser at construction time using the injected knowledge base).
+    Builder methods rely on it being already-sanitized — see module docstring.
+    """
 
     raw: str  # original release name (untouched)
     normalised: str  # dots instead of spaces
     title: str  # show/movie title (dots, no year/season/tech)
+    title_sanitized: str  # title with filesystem-forbidden chars stripped
     year: int | None  # movie year or show start year (from TMDB)
     season: int | None  # season number (None for movies)
     episode: int | None  # first episode number (None if season-pack)
@@ -180,14 +155,17 @@ class ParsedRelease:
     def is_season_pack(self) -> bool:
         return self.season is not None and self.episode is None
 
-    def show_folder_name(self, tmdb_title: str, tmdb_year: int) -> str:
+    def show_folder_name(self, tmdb_title_safe: str, tmdb_year: int) -> str:
         """
         Build the series root folder name.
 
         Format: {Title}.{Year}.{Tech}-{Group}
         Example: Oz.1997.1080p.WEBRip.x265-KONTRAST
+
+        ``tmdb_title_safe`` must already be filesystem-safe (the caller is
+        expected to have run it through ``kb.sanitize_for_fs``).
         """
-        title_part = _sanitize_for_fs(tmdb_title).replace(" ", ".")
+        title_part = tmdb_title_safe.replace(" ", ".")
         tech = self.tech_string or "Unknown"
         return f"{title_part}.{tmdb_year}.{tech}-{self.group}"
 
@@ -201,42 +179,45 @@ class ParsedRelease:
         """
         return _strip_episode_from_normalized(self.normalised)
 
-    def episode_filename(self, tmdb_episode_title: str | None, ext: str) -> str:
+    def episode_filename(self, tmdb_episode_title_safe: str | None, ext: str) -> str:
         """
         Build the episode filename.
 
         Format: {Title}.{SxxExx}.{EpisodeTitle}.{Tech}-{Group}.{ext}
         Example: Oz.S01E01.The.Routine.1080p.WEBRip.x265-KONTRAST.mkv
 
-        If tmdb_episode_title is None, omits the episode title segment.
+        ``tmdb_episode_title_safe`` must already be filesystem-safe; pass
+        ``None`` to omit the episode title segment.
         """
-        title_part = _sanitize_for_fs(self.title)
+        title_part = self.title_sanitized
         s = f"S{self.season:02d}" if self.season is not None else ""
         e = f"E{self.episode:02d}" if self.episode is not None else ""
         se = s + e
 
         ep_title = ""
-        if tmdb_episode_title:
-            ep_title = "." + _sanitize_for_fs(tmdb_episode_title).replace(" ", ".")
+        if tmdb_episode_title_safe:
+            ep_title = "." + tmdb_episode_title_safe.replace(" ", ".")
 
         tech = self.tech_string or "Unknown"
         ext_clean = ext.lstrip(".")
         return f"{title_part}.{se}{ep_title}.{tech}-{self.group}.{ext_clean}"
 
-    def movie_folder_name(self, tmdb_title: str, tmdb_year: int) -> str:
+    def movie_folder_name(self, tmdb_title_safe: str, tmdb_year: int) -> str:
         """
         Build the movie folder name.
 
         Format: {Title}.{Year}.{Tech}-{Group}
         Example: Inception.2010.1080p.BluRay.x265-GROUP
         """
-        return self.show_folder_name(tmdb_title, tmdb_year)
+        return self.show_folder_name(tmdb_title_safe, tmdb_year)
 
-    def movie_filename(self, tmdb_title: str, tmdb_year: int, ext: str) -> str:
+    def movie_filename(
+        self, tmdb_title_safe: str, tmdb_year: int, ext: str
+    ) -> str:
         """
         Build the movie filename (same as folder name + extension).
 
         Example: Inception.2010.1080p.BluRay.x265-GROUP.mkv
         """
         ext_clean = ext.lstrip(".")
-        return f"{self.movie_folder_name(tmdb_title, tmdb_year)}.{ext_clean}"
+        return f"{self.movie_folder_name(tmdb_title_safe, tmdb_year)}.{ext_clean}"
diff --git a/alfred/infrastructure/filesystem/find_video.py b/alfred/infrastructure/filesystem/find_video.py
index e91a290..9260331 100644
--- a/alfred/infrastructure/filesystem/find_video.py
+++ b/alfred/infrastructure/filesystem/find_video.py
@@ -4,10 +4,10 @@ from __future__ import annotations
 
 from pathlib import Path
 
-from alfred.domain.release.value_objects import _VIDEO_EXTENSIONS
+from alfred.domain.release.ports import ReleaseKnowledge
 
 
-def find_video_file(path: Path) -> Path | None:
+def find_video_file(path: Path, kb: ReleaseKnowledge) -> Path | None:
     """
     Return the first video file found at path.
 
@@ -15,11 +15,12 @@ def find_video_file(path: Path) -> Path | None:
     - If path is a folder — scan recursively, return the first video found
       (sorted by name for determinism, picks S01E01 before S01E02 etc.).
     """
+    video_exts = kb.video_extensions
     if path.is_file():
-        return path if path.suffix.lower() in _VIDEO_EXTENSIONS else None
+        return path if path.suffix.lower() in video_exts else None
 
     for candidate in sorted(path.rglob("*")):
-        if candidate.is_file() and candidate.suffix.lower() in _VIDEO_EXTENSIONS:
+        if candidate.is_file() and candidate.suffix.lower() in video_exts:
             return candidate
 
     return None
diff --git a/alfred/infrastructure/knowledge/release_kb.py b/alfred/infrastructure/knowledge/release_kb.py
new file mode 100644
index 0000000..5d4a790
--- /dev/null
+++ b/alfred/infrastructure/knowledge/release_kb.py
@@ -0,0 +1,83 @@
+"""YamlReleaseKnowledge — concrete adapter for the ``ReleaseKnowledge``
+domain port.
+
+Loads every release-knowledge YAML once at construction time and exposes
+the parsed snapshots as plain attributes. The application layer builds a
+single instance at boot and passes it down to ``parse_release`` and to
+``ParsedRelease`` builder methods.
+
+A few extras (``video_extensions``, ``non_video_extensions``,
+``subtitle_extensions``, ``metadata_extensions``) are not part of the
+domain port — they are consumed by application/infra modules that handle
+filesystem-level concerns.
+"""
+
+from __future__ import annotations
+
+from .release import (
+    load_audio,
+    load_codecs,
+    load_editions,
+    load_forbidden_chars,
+    load_hdr_extra,
+    load_language_tokens,
+    load_media_type_tokens,
+    load_metadata_extensions,
+    load_non_video_extensions,
+    load_resolutions,
+    load_separators,
+    load_sources,
+    load_sources_extra,
+    load_subtitle_extensions,
+    load_video,
+    load_video_extensions,
+    load_win_forbidden_chars,
+)
+
+
+class YamlReleaseKnowledge:
+    """Single object holding every parsed-release knowledge constant.
+
+    Built once at application boot. Read-only at runtime — call sites
+    treat it as a snapshot. To pick up newly learned tokens without a
+    restart, build a fresh instance and swap it in at the call sites.
+    """
+
+    def __init__(self) -> None:
+        # Domain-port surface
+        self.resolutions: set[str] = load_resolutions()
+        self.sources: set[str] = load_sources() | load_sources_extra()
+        self.codecs: set[str] = load_codecs()
+        self.language_tokens: set[str] = load_language_tokens()
+        self.forbidden_chars: set[str] = load_forbidden_chars()
+        self.hdr_extra: set[str] = load_hdr_extra()
+
+        self.audio: dict = load_audio()
+        self.video_meta: dict = load_video()
+        self.editions: dict = load_editions()
+        self.media_type_tokens: dict = load_media_type_tokens()
+
+        self.separators: list[str] = load_separators()
+
+        # File-extension sets (used by application/infra modules, not by
+        # the parser itself — kept here so there is a single ownership
+        # point for release knowledge).
+        self.video_extensions: set[str] = load_video_extensions()
+        self.non_video_extensions: set[str] = load_non_video_extensions()
+        self.subtitle_extensions: set[str] = load_subtitle_extensions()
+        # Metadata + subtitle extensions are both ignored when deciding
+        # the media type of a folder (neither is a conclusive signal for
+        # movie/tv/other), so we expose the union under the historical
+        # name.
+        self.metadata_extensions: set[str] = (
+            load_metadata_extensions() | self.subtitle_extensions
+        )
+
+        # Translation table for stripping Windows-forbidden chars.
+        self._win_forbidden_table = str.maketrans(
+            "", "", "".join(load_win_forbidden_chars())
+        )
+
+    def sanitize_for_fs(self, text: str) -> str:
+        """Strip Windows-forbidden characters from ``text``."""
+        return text.translate(self._win_forbidden_table)
diff --git a/tests/application/test_detect_media_type.py b/tests/application/test_detect_media_type.py
index 2041f0a..260aa0d 100644
--- a/tests/application/test_detect_media_type.py
+++ b/tests/application/test_detect_media_type.py
@@ -20,16 +20,19 @@ import pytest
 
 from alfred.application.filesystem.detect_media_type import detect_media_type
 from alfred.domain.release.services import parse_release
+from alfred.infrastructure.knowledge.release_kb import YamlReleaseKnowledge
+
+_KB = YamlReleaseKnowledge()
 
 
 def _parsed(media_type: str = "movie"):
     """Build a ParsedRelease with the requested media_type via the real parser."""
     if media_type == "tv_show":
-        return parse_release("Show.S01E01.1080p-GRP")
+        return parse_release("Show.S01E01.1080p-GRP", _KB)
     if media_type == "movie":
-        return parse_release("Movie.2020.1080p-GRP")
+        return parse_release("Movie.2020.1080p-GRP", _KB)
     # "unknown" / other — feed a name the parser can't classify
-    return parse_release("randomthing")
+    return parse_release("randomthing", _KB)
 
 
 # --------------------------------------------------------------------------- #
@@ -41,30 +44,30 @@ class TestFile:
     def test_video_file_preserves_parsed_type(self, tmp_path: Path):
         f = tmp_path / "x.mkv"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), f) == "movie"
+        assert detect_media_type(_parsed("movie"), f, _KB) == "movie"
 
     def test_video_file_preserves_tv_type(self, tmp_path: Path):
         f = tmp_path / "ep.mp4"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("tv_show"), f) == "tv_show"
+        assert detect_media_type(_parsed("tv_show"), f, _KB) == "tv_show"
 
     def test_non_video_file_returns_other(self, tmp_path: Path):
         f = tmp_path / "x.iso"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), f) == "other"
+        assert detect_media_type(_parsed("movie"), f, _KB) == "other"
 
     @pytest.mark.parametrize("ext", [".rar", ".zip", ".7z", ".exe", ".dmg"])
     def test_various_non_video_extensions(self, tmp_path: Path, ext):
         f = tmp_path / f"x{ext}"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), f) == "other"
+        assert detect_media_type(_parsed("movie"), f, _KB) == "other"
 
     def test_metadata_only_file_keeps_parsed_type(self, tmp_path: Path):
         # Metadata extension is stripped from conclusive set — no video, no
         # non-video → falls through to parsed.media_type.
         f = tmp_path / "x.nfo"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), f) == "movie"
+        assert detect_media_type(_parsed("movie"), f, _KB) == "movie"
 
 
 # --------------------------------------------------------------------------- #
@@ -75,27 +78,27 @@ class TestFile:
 class TestFolder:
     def test_folder_with_video_keeps_parsed_type(self, tmp_path: Path):
         (tmp_path / "main.mkv").write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), tmp_path) == "movie"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "movie"
 
     def test_folder_only_non_video_returns_other(self, tmp_path: Path):
         (tmp_path / "disc.iso").write_bytes(b"")
         (tmp_path / "part.rar").write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), tmp_path) == "other"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "other"
 
     def test_folder_mixed_returns_unknown(self, tmp_path: Path):
         (tmp_path / "main.mkv").write_bytes(b"")
         (tmp_path / "extras.iso").write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), tmp_path) == "unknown"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "unknown"
 
     def test_empty_folder_keeps_parsed_type(self, tmp_path: Path):
-        assert detect_media_type(_parsed("tv_show"), tmp_path) == "tv_show"
+        assert detect_media_type(_parsed("tv_show"), tmp_path, _KB) == "tv_show"
 
     def test_folder_only_metadata_keeps_parsed_type(self, tmp_path: Path):
         (tmp_path / "info.nfo").write_bytes(b"")
         (tmp_path / "cover.jpg").write_bytes(b"")
         (tmp_path / "subs.srt").write_bytes(b"")
         # All metadata → conclusive set empty → falls through.
-        assert detect_media_type(_parsed("movie"), tmp_path) == "movie"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "movie"
 
 
 # --------------------------------------------------------------------------- #
@@ -109,18 +112,18 @@ class TestMetadataIgnored:
         (tmp_path / "info.nfo").write_bytes(b"")
         (tmp_path / "cover.jpg").write_bytes(b"")
         (tmp_path / "subs.srt").write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), tmp_path) == "movie"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "movie"
 
     def test_non_video_plus_metadata_still_other(self, tmp_path: Path):
         (tmp_path / "disc.iso").write_bytes(b"")
         (tmp_path / "info.nfo").write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), tmp_path) == "other"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "other"
 
     def test_case_insensitive_extensions(self, tmp_path: Path):
         # Suffix is lowercased before classification.
         f = tmp_path / "X.MKV"
         f.write_bytes(b"")
-        assert detect_media_type(_parsed("movie"), f) == "movie"
+        assert detect_media_type(_parsed("movie"), f, _KB) == "movie"
 
 
 # --------------------------------------------------------------------------- #
@@ -132,11 +135,11 @@ class TestMissing:
     def test_nonexistent_path_keeps_parsed_type(self, tmp_path: Path):
         missing = tmp_path / "does_not_exist.mkv"
         # Doesn't exist → empty extension set → falls through.
-        assert detect_media_type(_parsed("movie"), missing) == "movie"
+        assert detect_media_type(_parsed("movie"), missing, _KB) == "movie"
 
     def test_nonexistent_folder_keeps_parsed_type(self, tmp_path: Path):
         missing = tmp_path / "ghost"
-        assert detect_media_type(_parsed("tv_show"), missing) == "tv_show"
+        assert detect_media_type(_parsed("tv_show"), missing, _KB) == "tv_show"
 
     def test_subfolder_not_recursed(self, tmp_path: Path):
         # _collect_extensions scans only the first level — files inside
@@ -145,4 +148,4 @@ class TestMissing:
         sub.mkdir()
         (sub / "deep.mkv").write_bytes(b"")
         # Top level has no files at all → empty → falls through to parsed type.
-        assert detect_media_type(_parsed("movie"), tmp_path) == "movie"
+        assert detect_media_type(_parsed("movie"), tmp_path, _KB) == "movie"
diff --git a/tests/application/test_enrich_from_probe.py b/tests/application/test_enrich_from_probe.py
index d40e21b..c192912 100644
--- a/tests/application/test_enrich_from_probe.py
+++ b/tests/application/test_enrich_from_probe.py
@@ -37,6 +37,7 @@ def _bare(**overrides) -> ParsedRelease:
         raw="X",
         normalised="X",
         title="X",
+        title_sanitized="X",
         year=None,
         season=None,
         episode=None,
diff --git a/tests/application/test_resolve_destination.py b/tests/application/test_resolve_destination.py
index ff7bc0c..1c67359 100644
--- a/tests/application/test_resolve_destination.py
+++ b/tests/application/test_resolve_destination.py
@@ -9,7 +9,6 @@ Four use cases compute library paths from a release name + TMDB metadata:
 
 Coverage:
 
-- ``TestSanitize`` — Windows-forbidden chars stripped.
 - ``TestFindExistingTvshowFolders`` — empty root, prefix match (case + space → dot).
 - ``TestResolveSeriesFolderInternal`` — confirmed_folder, no existing, single match,
   ambiguous → _Clarification.
@@ -32,7 +31,6 @@ from alfred.application.filesystem.resolve_destination import (
     _Clarification,
     _find_existing_tvshow_folders,
     _resolve_series_folder,
-    _sanitize,
     resolve_episode_destination,
     resolve_movie_destination,
     resolve_season_destination,
@@ -51,15 +49,6 @@ REL_SERIES = "Oz.Complete.Series.1080p.WEBRip.x265-KONTRAST"
 # --------------------------------------------------------------------------- #
 
 
-class TestSanitize:
-    def test_passthrough_safe_chars(self):
-        assert _sanitize("Oz.1997.1080p-GRP") == "Oz.1997.1080p-GRP"
-
-    def test_strips_windows_forbidden(self):
-        # ? : * " < > | \
-        assert _sanitize('a?b:c*d"e<f>g|h\\i') == "abcdefghi"
-
-
 # --------------------------------------------------------------------------- #
 # _find_existing_tvshow_folders                                                #
 # --------------------------------------------------------------------------- #
@@ -107,6 +96,7 @@ class TestResolveSeriesFolderInternal:
         out = _resolve_series_folder(
             tmp_path,
             "Oz",
+            "Oz",
             1997,
             "Oz.1997.WEBRip-KONTRAST",
             confirmed_folder="Oz.1997.X-GRP",
@@ -117,6 +107,7 @@ class TestResolveSeriesFolderInternal:
         out = _resolve_series_folder(
             tmp_path,
             "Oz",
+            "Oz",
             1997,
             "Oz.1997.WEBRip-KONTRAST",
             confirmed_folder="Oz.1997.New-X",
@@ -125,21 +116,21 @@ class TestResolveSeriesFolderInternal:
 
     def test_no_existing_returns_computed_as_new(self, tmp_path):
         out = _resolve_series_folder(
-            tmp_path, "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
+            tmp_path, "Oz", "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
         )
         assert out == ("Oz.1997.WEBRip-KONTRAST", True)
 
     def test_single_existing_matching_computed_returns_existing(self, tmp_path):
         (tmp_path / "Oz.1997.WEBRip-KONTRAST").mkdir()
         out = _resolve_series_folder(
-            tmp_path, "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
+            tmp_path, "Oz", "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
         )
         assert out == ("Oz.1997.WEBRip-KONTRAST", False)
 
     def test_single_existing_different_name_returns_clarification(self, tmp_path):
         (tmp_path / "Oz.1997.BluRay-OTHER").mkdir()
         out = _resolve_series_folder(
-            tmp_path, "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
+            tmp_path, "Oz", "Oz", 1997, "Oz.1997.WEBRip-KONTRAST", None
         )
         assert isinstance(out, _Clarification)
         assert "Oz" in out.question
@@ -149,7 +140,7 @@ class TestResolveSeriesFolderInternal:
     def test_multiple_existing_returns_clarification(self, tmp_path):
         (tmp_path / "Oz.1997.A-GRP").mkdir()
         (tmp_path / "Oz.1997.B-GRP").mkdir()
-        out = _resolve_series_folder(tmp_path, "Oz", 1997, "Oz.1997.A-GRP", None)
+        out = _resolve_series_folder(tmp_path, "Oz", "Oz", 1997, "Oz.1997.A-GRP", None)
         assert isinstance(out, _Clarification)
         # Computed already in existing → not duplicated.
         assert out.options.count("Oz.1997.A-GRP") == 1
diff --git a/tests/domain/test_release.py b/tests/domain/test_release.py
index d3005cb..f44a6cf 100644
--- a/tests/domain/test_release.py
+++ b/tests/domain/test_release.py
@@ -20,13 +20,20 @@ import pytest
 
 from alfred.domain.release.services import parse_release
 from alfred.domain.release.value_objects import ParsedRelease
+from alfred.infrastructure.knowledge.release_kb import YamlReleaseKnowledge
+
+_KB = YamlReleaseKnowledge()
+
+
+def _parse(name: str) -> ParsedRelease:
+    return parse_release(name, _KB)
 
 
 class TestParseTVEpisode:
     """Single-episode TV releases."""
 
     def test_basic_tv_episode(self):
-        r = parse_release("Oz.S03E01.1080p.WEBRip.x265-KONTRAST")
+        r = _parse("Oz.S03E01.1080p.WEBRip.x265-KONTRAST")
         assert r.title == "Oz"
         assert r.season == 3
         assert r.episode == 1
@@ -40,27 +47,27 @@ class TestParseTVEpisode:
         assert r.is_season_pack is False
 
     def test_multi_episode(self):
-        r = parse_release("Archer.S14E09E10.1080p.WEB.x265-GRP")
+        r = _parse("Archer.S14E09E10.1080p.WEB.x265-GRP")
         assert r.season == 14
         assert r.episode == 9
         assert r.episode_end == 10
 
     def test_nxnn_alt_form(self):
         # Alt season/episode form: 1x05 instead of S01E05.
-        r = parse_release("Some.Show.1x05.720p.HDTV.x264-GRP")
+        r = _parse("Some.Show.1x05.720p.HDTV.x264-GRP")
         assert r.season == 1
         assert r.episode == 5
         assert r.episode_end is None
         assert r.media_type == "tv_show"
 
     def test_nxnnxnn_multi_episode_alt_form(self):
-        r = parse_release("Some.Show.2x07x08.1080p.WEB.x265-GRP")
+        r = _parse("Some.Show.2x07x08.1080p.WEB.x265-GRP")
         assert r.season == 2
         assert r.episode == 7
         assert r.episode_end == 8
 
     def test_season_pack(self):
-        r = parse_release("Oz.S03.1080p.WEBRip.x265-KONTRAST")
+        r = _parse("Oz.S03.1080p.WEBRip.x265-KONTRAST")
         assert r.season == 3
         assert r.episode is None
         assert r.is_season_pack is True
@@ -71,7 +78,7 @@ class TestParseMovie:
     """Movie releases."""
 
     def test_basic_movie(self):
-        r = parse_release("Inception.2010.1080p.BluRay.x264-GROUP")
+        r = _parse("Inception.2010.1080p.BluRay.x264-GROUP")
         assert r.title == "Inception"
         assert r.year == 2010
         assert r.season is None
@@ -83,13 +90,13 @@ class TestParseMovie:
         assert r.media_type == "movie"
 
     def test_movie_multi_word_title(self):
-        r = parse_release("The.Dark.Knight.2008.2160p.UHD.BluRay.x265-TERMINAL")
+        r = _parse("The.Dark.Knight.2008.2160p.UHD.BluRay.x265-TERMINAL")
         assert r.title == "The.Dark.Knight"
         assert r.year == 2008
         assert r.quality == "2160p"
 
     def test_movie_without_year_still_movie_if_tech_present(self):
-        r = parse_release("UntitledFilm.1080p.WEBRip.x264-GRP")
+        r = _parse("UntitledFilm.1080p.WEBRip.x264-GRP")
         # No season, no year, but tech markers → still movie
         assert r.media_type == "movie"
         assert r.year is None
@@ -99,39 +106,39 @@ class TestParseEdgeCases:
     """Site tags, malformed names, and unknown media types."""
 
     def test_site_tag_prefix_stripped(self):
-        r = parse_release("[ OxTorrent.vc ] The.Title.S01E01.1080p.WEB.x265-GRP")
+        r = _parse("[ OxTorrent.vc ] The.Title.S01E01.1080p.WEB.x265-GRP")
         assert r.site_tag == "OxTorrent.vc"
         assert r.parse_path == "sanitized"
         assert r.season == 1
         assert r.episode == 1
 
     def test_site_tag_suffix_stripped(self):
-        r = parse_release("The.Title.S01E01.1080p.WEB.x265-NTb[TGx]")
+        r = _parse("The.Title.S01E01.1080p.WEB.x265-NTb[TGx]")
         assert r.site_tag == "TGx"
         # Suffix-tagged names are well-formed (only [] in tag → after strip clean)
         assert r.season == 1
 
     def test_irrecoverably_malformed(self):
         # @ is a forbidden char and not stripped by _sanitize → stays malformed
-        r = parse_release("foo@bar@baz")
+        r = _parse("foo@bar@baz")
         assert r.media_type == "unknown"
         assert r.parse_path == "ai"
         assert r.group == "UNKNOWN"
 
     def test_empty_unknown_when_no_evidence(self):
-        r = parse_release("Some.Random.Title")
+        r = _parse("Some.Random.Title")
         # No season, no year, no tech markers → unknown
         assert r.media_type == "unknown"
 
     def test_missing_group_defaults_to_unknown(self):
-        r = parse_release("Movie.2020.1080p.WEBRip.x265")
+        r = _parse("Movie.2020.1080p.WEBRip.x265")
         # No "-GROUP" suffix → group = "UNKNOWN"
         assert r.group == "UNKNOWN"
 
     def test_yts_bracket_release(self):
         # YTS-style: spaces, parens for year, multiple bracketed tech tokens.
         # The tokenizer must handle ' ', '(', ')', '[', ']' transparently.
-        r = parse_release("The Father (2020) [1080p] [WEBRip] [5.1] [YTS.MX]")
+        r = _parse("The Father (2020) [1080p] [WEBRip] [5.1] [YTS.MX]")
         assert r.title == "The.Father"
         assert r.year == 2020
         assert r.quality == "1080p"
@@ -141,7 +148,7 @@ class TestParseEdgeCases:
 
     def test_human_friendly_spaces(self):
         # Spaces as separators (no brackets).
-        r = parse_release("Inception 2010 1080p BluRay x264-GROUP")
+        r = _parse("Inception 2010 1080p BluRay x264-GROUP")
         assert r.title == "Inception"
         assert r.year == 2010
         assert r.quality == "1080p"
@@ -151,7 +158,7 @@ class TestParseEdgeCases:
 
     def test_underscore_separators(self):
         # Old usenet style: underscores between tokens.
-        r = parse_release("Some_Show_S01E01_1080p_WEB_x265-GRP")
+        r = _parse("Some_Show_S01E01_1080p_WEB_x265-GRP")
         assert r.season == 1
         assert r.episode == 1
         assert r.quality == "1080p"
@@ -162,15 +169,15 @@ class TestParseAudioVideoEdition:
     """Audio, video metadata, edition extraction."""
 
     def test_audio_codec_and_channels(self):
-        r = parse_release("Movie.2020.1080p.BluRay.DTS.5.1.x264-GRP")
+        r = _parse("Movie.2020.1080p.BluRay.DTS.5.1.x264-GRP")
         assert r.audio_channels == "5.1"
 
     def test_language_token(self):
-        r = parse_release("Movie.2020.MULTI.1080p.WEBRip.x265-GRP")
+        r = _parse("Movie.2020.MULTI.1080p.WEBRip.x265-GRP")
         assert "MULTI" in r.languages
 
     def test_edition_token(self):
-        r = parse_release("Movie.2020.UNRATED.1080p.BluRay.x264-GRP")
+        r = _parse("Movie.2020.UNRATED.1080p.BluRay.x264-GRP")
         assert r.edition == "UNRATED"
 
 
@@ -178,19 +185,21 @@ class TestParsedReleaseFolderNames:
     """Helpers that build filesystem-safe folder/filenames."""
 
     def _parsed_tv(self) -> ParsedRelease:
-        return parse_release("Oz.S03E01.1080p.WEBRip.x265-KONTRAST")
+        return _parse("Oz.S03E01.1080p.WEBRip.x265-KONTRAST")
 
     def _parsed_movie(self) -> ParsedRelease:
-        return parse_release("Inception.2010.1080p.BluRay.x264-GROUP")
+        return _parse("Inception.2010.1080p.BluRay.x264-GROUP")
 
     def test_show_folder_name(self):
         r = self._parsed_tv()
         assert r.show_folder_name("Oz", 1997) == "Oz.1997.1080p.WEBRip.x265-KONTRAST"
 
-    def test_show_folder_name_strips_windows_chars(self):
+    def test_show_folder_name_uses_already_safe_title(self):
+        # Option B: callers sanitize at the use-case boundary via
+        # kb.sanitize_for_fs(...) before passing the title in.
         r = self._parsed_tv()
-        # Colons and question marks are Windows-forbidden — must be stripped.
-        result = r.show_folder_name("Oz: The Series?", 1997)
+        safe = _KB.sanitize_for_fs("Oz: The Series?")
+        result = r.show_folder_name(safe, 1997)
         assert ":" not in result
         assert "?" not in result
 
@@ -202,7 +211,7 @@ class TestParsedReleaseFolderNames:
         assert "E01" not in result
 
     def test_season_folder_name_multi_episode(self):
-        r = parse_release("Archer.S14E09E10E11.1080p.WEB.x265-GRP")
+        r = _parse("Archer.S14E09E10E11.1080p.WEB.x265-GRP")
         result = r.season_folder_name()
         assert "S14" in result
         assert "E09" not in result
@@ -251,21 +260,21 @@ class TestParsedReleaseInvariants:
 
     def test_raw_is_preserved(self):
         raw = "Oz.S03E01.1080p.WEBRip.x265-KONTRAST"
-        r = parse_release(raw)
+        r = _parse(raw)
         assert r.raw == raw
 
     def test_languages_defaults_to_empty_list_not_none(self):
-        r = parse_release("Movie.2020.1080p.BluRay.x264-GRP")
+        r = _parse("Movie.2020.1080p.BluRay.x264-GRP")
         # __post_init__ ensures languages is a list, never None
         assert r.languages == []
 
     def test_tech_string_joined(self):
-        r = parse_release("Movie.2020.1080p.BluRay.x264-GRP")
+        r = _parse("Movie.2020.1080p.BluRay.x264-GRP")
         assert r.tech_string == "1080p.BluRay.x264"
 
     def test_tech_string_partial(self):
         # Codec-only release (no quality/source): tech_string == codec
-        r = parse_release("Show.S01E01.x265-GRP")
+        r = _parse("Show.S01E01.x265-GRP")
         assert r.tech_string == "x265"
         assert r.codec == "x265"
         assert r.quality is None
@@ -280,4 +289,4 @@ class TestParsedReleaseInvariants:
         ],
     )
     def test_media_type_inference(self, name, expected_type):
-        assert parse_release(name).media_type == expected_type
+        assert _parse(name).media_type == expected_type
diff --git a/tests/domain/test_release_fixtures.py b/tests/domain/test_release_fixtures.py
index dd7d0dd..31f3fff 100644
--- a/tests/domain/test_release_fixtures.py
+++ b/tests/domain/test_release_fixtures.py
@@ -19,8 +19,10 @@ from dataclasses import asdict
 import pytest
 
 from alfred.domain.release.services import parse_release
+from alfred.infrastructure.knowledge.release_kb import YamlReleaseKnowledge
 from tests.fixtures.releases.conftest import ReleaseFixture, discover_fixtures
 
+_KB = YamlReleaseKnowledge()
 FIXTURES = discover_fixtures()
 
 
@@ -34,9 +36,9 @@ def test_parse_matches_fixture(fixture: ReleaseFixture, tmp_path) -> None:
     # plausible filesystem paths. Catches typos / missing leading dirs early.
     fixture.materialize(tmp_path)
 
-    result = asdict(parse_release(fixture.release_name))
+    result = asdict(parse_release(fixture.release_name, _KB))
     # ``is_season_pack`` is a @property — asdict() does not include it.
-    result["is_season_pack"] = parse_release(fixture.release_name).is_season_pack
+    result["is_season_pack"] = parse_release(fixture.release_name, _KB).is_season_pack
 
     for field, expected in fixture.expected_parsed.items():
         assert field in result, (
diff --git a/tests/infrastructure/test_filesystem_extras.py b/tests/infrastructure/test_filesystem_extras.py
index 29ad832..6988489 100644
--- a/tests/infrastructure/test_filesystem_extras.py
+++ b/tests/infrastructure/test_filesystem_extras.py
@@ -34,6 +34,9 @@ from alfred.infrastructure.filesystem.filesystem_operations import (
 )
 from alfred.infrastructure.filesystem.find_video import find_video_file
 from alfred.infrastructure.filesystem.organizer import MediaOrganizer
+from alfred.infrastructure.knowledge.release_kb import YamlReleaseKnowledge
+
+_KB = YamlReleaseKnowledge()
 
 # --------------------------------------------------------------------------- #
 # ffprobe.probe                                                                #
@@ -263,35 +266,35 @@ class TestFindVideo:
     def test_returns_file_directly_when_video(self, tmp_path):
         f = tmp_path / "Movie.mkv"
         f.write_bytes(b"")
-        assert find_video_file(f) == f
+        assert find_video_file(f, _KB) == f
 
     def test_returns_none_when_file_is_not_video(self, tmp_path):
         f = tmp_path / "notes.txt"
         f.write_text("x")
-        assert find_video_file(f) is None
+        assert find_video_file(f, _KB) is None
 
     def test_returns_none_when_folder_has_no_video(self, tmp_path):
         (tmp_path / "a.txt").write_text("x")
-        assert find_video_file(tmp_path) is None
+        assert find_video_file(tmp_path, _KB) is None
 
     def test_returns_first_sorted_video(self, tmp_path):
         (tmp_path / "B.mkv").write_bytes(b"")
         (tmp_path / "A.mkv").write_bytes(b"")
         (tmp_path / "C.mkv").write_bytes(b"")
-        found = find_video_file(tmp_path)
+        found = find_video_file(tmp_path, _KB)
         assert found.name == "A.mkv"
 
     def test_recurses_into_subfolders(self, tmp_path):
         sub = tmp_path / "sub"
         sub.mkdir()
         (sub / "X.mkv").write_bytes(b"")
-        found = find_video_file(tmp_path)
+        found = find_video_file(tmp_path, _KB)
         assert found is not None and found.name == "X.mkv"
 
     def test_case_insensitive_extension(self, tmp_path):
         f = tmp_path / "Movie.MKV"
         f.write_bytes(b"")
-        assert find_video_file(f) == f
+        assert find_video_file(f, _KB) == f
 
 
 # --------------------------------------------------------------------------- #