diff --git a/crates/arr-core/src/lib.rs b/crates/arr-core/src/lib.rs
index 328b332..be1badf 100644
--- a/crates/arr-core/src/lib.rs
+++ b/crates/arr-core/src/lib.rs
@@ -1,14 +1,290 @@
-//! arr-core — domain types, policy engine, scoring. See DESIGN.md §4 and §5.
+//! Pure domain types shared by the arr crates.
 //!
-//! This crate must never depend on `axum`, `sqlx` or `reqwest`. It holds the
-//! logic that is tested constantly and it has to stay fast to compile.
+//! This crate must never depend on `axum`, `sqlx` or `reqwest`.
+
+use std::{collections::BTreeMap, path::PathBuf, time::SystemTime};
+
+macro_rules! id_type {
+    ($name:ident) => {
+        #[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+        pub struct $name(pub i64);
+    };
+}
+
+id_type!(RootId);
+id_type!(PolicyId);
+id_type!(MovieId);
+id_type!(MediaFileId);
+id_type!(ReleaseId);
+id_type!(GrabId);
+id_type!(OwnerId);
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum Audience {
+    Main,
+    Kids,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Root {
+    pub id: RootId,
+    pub audience: Audience,
+    pub path: PathBuf,
+    pub policy_id: PolicyId,
+}
+
+#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Language {
+    PortuguesePortugal,
+    PortugueseBrazil,
+    PortugueseUnverified,
+    Other(String),
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Resolution {
+    R2160p,
+    R1080p,
+    R720p,
+    Other(u16),
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Source {
+    Remux,
+    BluRay,
+    WebDl,
+    WebRip,
+    Hdtv,
+    Telesync,
+    Cam,
+    Screener,
+    Other,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct DolbyVisionProfile {
+    pub profile: u8,
+    pub compatibility_id: Option<u8>,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum HdrFormat {
+    Sdr,
+    Hdr10,
+    Hdr10Plus,
+    Hlg,
+    DolbyVision(DolbyVisionProfile),
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum HdrClaim {
+    Hdr10,
+    Hdr10Plus,
+    Hlg,
+    DolbyVision,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub enum RequiredAudio {
+    OriginalLanguage,
+    AnyOf(Vec<Language>),
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct HdrRules {
+    pub rejected_dolby_vision_profiles: Vec<DolbyVisionProfile>,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct SizeBand {
+    pub floor_bytes: u64,
+    pub target_bytes: u64,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Policy {
+    pub id: PolicyId,
+    pub name: String,
+    pub required_audio: RequiredAudio,
+    pub dub_blacklist: Vec<Language>,
+    pub hdr_rules: HdrRules,
+    pub size_bands: BTreeMap<Resolution, SizeBand>,
+    pub resolution_preference: Vec<Resolution>,
+    pub source_weights: BTreeMap<Source, i32>,
+}
+
+#[derive(Clone, Debug, Default, Eq, PartialEq)]
+pub struct MovieOverrides {
+    pub only_4k: bool,
+    pub allow_english_audio: bool,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum MovieState {
+    Missing,
+    Downloading,
+    Available,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Movie {
+    pub id: MovieId,
+    pub tmdb_id: u64,
+    pub title: String,
+    pub year: u16,
+    pub original_language: Language,
+    pub root_id: RootId,
+    pub wanted: bool,
+    pub overrides: MovieOverrides,
+    pub state: MovieState,
+    pub blocked: bool,
+    pub search_attempts: u32,
+    pub last_searched_at: Option<SystemTime>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct AudioTrack {
+    pub language: Language,
+    pub title: Option<String>,
+    pub handler_name: Option<String>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct SubtitleTrack {
+    pub language: Language,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct ProbedMedia {
+    pub resolution: Resolution,
+    pub source: Option<Source>,
+    pub hdr: HdrFormat,
+    pub audio_tracks: Vec<AudioTrack>,
+    pub subtitle_tracks: Vec<SubtitleTrack>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub enum Rule {
+    RequiredAudio,
+    DubBlacklist(Language),
+    DolbyVisionProfile(DolbyVisionProfile),
+    Resolution(Resolution),
+    Source(Source),
+    Size,
+    Other(String),
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub enum Verdict {
+    Eligible,
+    Waived(Rule),
+    Rejected(Rule),
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct MediaFile {
+    pub id: MediaFileId,
+    pub movie_id: MovieId,
+    pub path: PathBuf,
+    pub size: u64,
+    pub probed: ProbedMedia,
+    pub waiver: Option<Rule>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct ParsedRelease {
+    pub resolution: Option<Resolution>,
+    pub source: Option<Source>,
+    pub hdr: Vec<HdrClaim>,
+    pub audio_languages: Vec<Language>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Release {
+    pub id: ReleaseId,
+    pub indexer_id: i64,
+    pub guid: String,
+    pub name: String,
+    pub size: u64,
+    pub seeders: u32,
+    pub publish_date: SystemTime,
+    pub download_url: String,
+    pub parsed: ParsedRelease,
+    pub score: i64,
+    pub verdict: Verdict,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum GrabState {
+    Downloading,
+    Downloaded,
+    Imported,
+    Failed,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Grab {
+    pub id: GrabId,
+    pub release_id: ReleaseId,
+    pub movie_id: MovieId,
+    pub infohash: String,
+    pub state: GrabState,
+    pub grabbed_at: SystemTime,
+    pub imported_at: Option<SystemTime>,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct BlacklistEntry {
+    pub infohash: String,
+    pub normalised_name: String,
+    pub reason: String,
+    pub created_at: SystemTime,
+}
+
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct Owner {
+    pub id: OwnerId,
+    pub name: String,
+    pub ntfy_topic: String,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct MovieOwner {
+    pub movie_id: MovieId,
+    pub owner_id: OwnerId,
+}
 
 #[cfg(test)]
 mod tests {
-    /// Placeholder so the test gate is meaningful on an empty workspace —
-    /// `cargo nextest` fails a run with zero tests, and relaxing that would
-    /// let a broken filter go green later. Replaced by real tests in the
-    /// domain-types and policy-engine issues.
+    use super::{DolbyVisionProfile, HdrFormat, Language, Rule, Verdict};
+
     #[test]
-    fn workspace_builds_and_tests_run() {}
+    fn portuguese_variants_are_distinct() {
+        assert_ne!(Language::PortuguesePortugal, Language::PortugueseBrazil);
+        assert_ne!(Language::PortugueseBrazil, Language::PortugueseUnverified);
+    }
+
+    #[test]
+    fn dolby_vision_profile_is_preserved() {
+        assert_ne!(
+            HdrFormat::DolbyVision(DolbyVisionProfile {
+                profile: 8,
+                compatibility_id: Some(1),
+            }),
+            HdrFormat::DolbyVision(DolbyVisionProfile {
+                profile: 8,
+                compatibility_id: Some(2),
+            })
+        );
+    }
+
+    #[test]
+    fn non_eligible_verdicts_name_the_rule() {
+        let rule = Rule::DolbyVisionProfile(DolbyVisionProfile {
+            profile: 5,
+            compatibility_id: None,
+        });
+        assert_eq!(Verdict::Rejected(rule.clone()), Verdict::Rejected(rule));
+    }
 }