add 400+ unit tests for domain and application layers

Extract ReviewLogger trait to decouple import/integrations
from diary::log_review (cross-module coupling smell).

Add in-memory fakes for all repository ports, enabling
isolated testing of every use case module without a database.

Coverage: domain+application 22% → 80%, 427 tests.

crates/domain/src/testing/fakes.rs

@@ -8,12 +8,16 @@ use uuid::Uuid;
 use crate::{
     errors::DomainError,
     models::{
-        DiaryEntry, DiaryFilter, FeedEntry, Movie, MovieStats, Review, ReviewHistory,
+        AnnotatedRow, DiaryEntry, DiaryFilter, ExternalPersonId, FeedEntry, FieldMapping,
+        FileFormat, ImportError, ImportRow, Movie, MovieProfile, MovieStats, ParsedFile, Person,
+        PersonCredits, PersonId, Review, ReviewHistory, RowResult, SearchQuery, SearchResults,
+        UserStats, UserTrends,
         collections::{PageParams, Paginated},
     },
     ports::{
-        AuthService, DiaryRepository, FeedSortBy, FollowingFilter, GeneratedToken, MetadataClient,
-        MetadataSearchCriteria, PasswordHasher,
+        AuthService, DiaryRepository, DocumentParser, FeedSortBy, FollowingFilter, GeneratedToken,
+        MetadataClient, MetadataSearchCriteria, MovieEnrichmentClient, PasswordHasher, PersonQuery,
+        PosterFetcherClient, SearchCommand, SearchPort, StatsRepository,
     },
     value_objects::{ExternalMetadataId, MovieId, PasswordHash, PosterUrl, UserId},
 };
@@ -103,14 +107,24 @@ impl DiaryRepository for FakeDiaryRepository {
         &self,
         _filter: &DiaryFilter,
     ) -> Result<Paginated<DiaryEntry>, DomainError> {
-        unimplemented!("FakeDiaryRepository::query_diary")
+        Ok(Paginated {
+            items: vec![],
+            total_count: 0,
+            limit: 10,
+            offset: 0,
+        })
     }
 
     async fn query_activity_feed(
         &self,
         _page: &PageParams,
     ) -> Result<Paginated<FeedEntry>, DomainError> {
-        unimplemented!("FakeDiaryRepository::query_activity_feed")
+        Ok(Paginated {
+            items: vec![],
+            total_count: 0,
+            limit: 10,
+            offset: 0,
+        })
     }
 
     async fn query_activity_feed_filtered(
@@ -120,7 +134,12 @@ impl DiaryRepository for FakeDiaryRepository {
         _search: Option<&str>,
         _following: Option<&FollowingFilter>,
     ) -> Result<Paginated<FeedEntry>, DomainError> {
-        unimplemented!("FakeDiaryRepository::query_activity_feed_filtered")
+        Ok(Paginated {
+            items: vec![],
+            total_count: 0,
+            limit: 10,
+            offset: 0,
+        })
     }
 
     async fn get_review_history(&self, movie_id: &MovieId) -> Result<ReviewHistory, DomainError> {
@@ -132,11 +151,16 @@ impl DiaryRepository for FakeDiaryRepository {
     }
 
     async fn get_user_history(&self, _user_id: &UserId) -> Result<Vec<DiaryEntry>, DomainError> {
-        unimplemented!("FakeDiaryRepository::get_user_history")
+        Ok(vec![])
     }
 
     async fn get_movie_stats(&self, _movie_id: &MovieId) -> Result<MovieStats, DomainError> {
-        unimplemented!("FakeDiaryRepository::get_movie_stats")
+        Ok(MovieStats {
+            total_count: 0,
+            avg_rating: None,
+            federated_count: 0,
+            rating_histogram: [0; 5],
+        })
     }
 
     async fn get_movie_social_feed(
@@ -144,10 +168,186 @@ impl DiaryRepository for FakeDiaryRepository {
         _movie_id: &MovieId,
         _page: &PageParams,
     ) -> Result<Paginated<FeedEntry>, DomainError> {
-        unimplemented!("FakeDiaryRepository::get_movie_social_feed")
+        Ok(Paginated {
+            items: vec![],
+            total_count: 0,
+            limit: 10,
+            offset: 0,
+        })
     }
 
     async fn count_local_posts(&self) -> Result<u64, DomainError> {
-        unimplemented!("FakeDiaryRepository::count_local_posts")
+        Ok(0)
+    }
+}
+
+// ── FakeStatsRepository ─────────────────────────────────────────────────────
+
+pub struct FakeStatsRepository;
+
+#[async_trait]
+impl StatsRepository for FakeStatsRepository {
+    async fn get_user_stats(&self, _: &UserId) -> Result<UserStats, DomainError> {
+        Ok(UserStats {
+            total_movies: 0,
+            avg_rating: None,
+            favorite_director: None,
+            most_active_month: None,
+        })
+    }
+
+    async fn get_user_trends(&self, _: &UserId) -> Result<UserTrends, DomainError> {
+        Ok(UserTrends {
+            monthly_ratings: vec![],
+            top_directors: vec![],
+            max_director_count: 0,
+        })
+    }
+}
+
+// ── FakePersonQuery ─────────────────────────────────────────────────────────
+
+pub struct FakePersonQuery;
+
+#[async_trait]
+impl PersonQuery for FakePersonQuery {
+    async fn get_by_id(&self, _: &PersonId) -> Result<Option<Person>, DomainError> {
+        Ok(None)
+    }
+
+    async fn get_by_external_id(
+        &self,
+        _: &ExternalPersonId,
+    ) -> Result<Option<Person>, DomainError> {
+        Ok(None)
+    }
+
+    async fn get_credits(&self, id: &PersonId) -> Result<PersonCredits, DomainError> {
+        let dummy = Person::new(
+            id.clone(),
+            ExternalPersonId::new("tmdb:0"),
+            "Unknown".into(),
+            None,
+            None,
+        );
+        Ok(PersonCredits {
+            person: dummy,
+            cast: vec![],
+            crew: vec![],
+        })
+    }
+
+    async fn list_orphaned_persons(&self) -> Result<Vec<PersonId>, DomainError> {
+        Ok(vec![])
+    }
+
+    async fn list_page(&self, _: u32, _: u32) -> Result<Vec<Person>, DomainError> {
+        Ok(vec![])
+    }
+}
+
+// ── FakeSearchPort ──────────────────────────────────────────────────────────
+
+pub struct FakeSearchPort;
+
+#[async_trait]
+impl SearchPort for FakeSearchPort {
+    async fn search(&self, _: &SearchQuery) -> Result<SearchResults, DomainError> {
+        Ok(SearchResults {
+            movies: Paginated {
+                items: vec![],
+                total_count: 0,
+                limit: 10,
+                offset: 0,
+            },
+            people: Paginated {
+                items: vec![],
+                total_count: 0,
+                limit: 10,
+                offset: 0,
+            },
+        })
+    }
+}
+
+// ── FakeSearchCommand ───────────────────────────────────────────────────────
+
+pub struct FakeSearchCommand;
+
+#[async_trait]
+impl SearchCommand for FakeSearchCommand {
+    async fn index(&self, _: crate::models::IndexableDocument) -> Result<(), DomainError> {
+        Ok(())
+    }
+
+    async fn remove(&self, _: crate::models::EntityType, _: &str) -> Result<(), DomainError> {
+        Ok(())
+    }
+}
+
+// ── FakeDocumentParser ──────────────────────────────────────────────────────
+
+pub struct FakeDocumentParser;
+
+impl DocumentParser for FakeDocumentParser {
+    fn parse(&self, _: &[u8], _: FileFormat) -> Result<ParsedFile, ImportError> {
+        Ok(ParsedFile {
+            columns: vec!["title".into()],
+            rows: vec![vec!["Test Movie".into()]],
+        })
+    }
+
+    fn apply_mapping(&self, _: &ParsedFile, _: &[FieldMapping]) -> Vec<AnnotatedRow> {
+        vec![AnnotatedRow {
+            result: RowResult::Valid(ImportRow {
+                title: Some("Test Movie".into()),
+                ..ImportRow::default()
+            }),
+            is_duplicate: false,
+        }]
+    }
+}
+
+// ── FakePosterFetcher ───────────────────────────────────────────────────────
+
+pub struct FakePosterFetcher;
+
+#[async_trait]
+impl PosterFetcherClient for FakePosterFetcher {
+    async fn fetch_poster_bytes(&self, _: &PosterUrl) -> Result<Vec<u8>, DomainError> {
+        Ok(vec![1, 2, 3])
+    }
+}
+
+// ── FakeMovieEnrichmentClient ───────────────────────────────────────────────
+
+pub struct FakeMovieEnrichmentClient;
+
+#[async_trait]
+impl MovieEnrichmentClient for FakeMovieEnrichmentClient {
+    async fn fetch_profile(
+        &self,
+        movie_id: MovieId,
+        _external_metadata_id: &str,
+    ) -> Result<MovieProfile, DomainError> {
+        Ok(MovieProfile {
+            movie_id,
+            tmdb_id: 0,
+            imdb_id: None,
+            overview: None,
+            tagline: None,
+            runtime_minutes: None,
+            budget_usd: None,
+            revenue_usd: None,
+            vote_average: None,
+            vote_count: None,
+            original_language: None,
+            collection_name: None,
+            genres: vec![],
+            keywords: vec![],
+            cast: vec![],
+            crew: vec![],
+            enriched_at: Utc::now(),
+        })
     }
 }

crates/domain/src/testing/in_memory.rs

@@ -4,17 +4,25 @@ use std::sync::{Arc, Mutex};
 use async_trait::async_trait;
 use uuid::Uuid;
 
+use chrono::NaiveDateTime;
+
 use crate::{
     errors::DomainError,
     events::DomainEvent,
     models::{
-        Movie, MovieFilter, MovieSummary, Review, User, UserSummary, WatchlistEntry,
-        WatchlistWithMovie,
+        Goal, ImportProfile, ImportSession, Movie, MovieFilter, MovieProfile, MovieSummary,
+        ProfileField, Review, User, UserSettings, UserSummary, WatchEvent, WatchEventStatus,
+        WatchlistEntry, WatchlistWithMovie, WebhookToken,
         collections::{PageParams, Paginated},
     },
-    ports::{MovieRepository, ReviewRepository, UserRepository, WatchlistRepository},
+    ports::{
+        GoalRepository, ImportProfileRepository, ImportSessionRepository, MovieProfileRepository,
+        MovieRepository, ReviewRepository, UserProfileFieldsRepository, UserRepository,
+        UserSettingsRepository, WatchEventRepository, WatchlistRepository, WebhookTokenRepository,
+    },
     value_objects::{
-        Email, ExternalMetadataId, MovieId, MovieTitle, ReleaseYear, ReviewId, UserId, Username,
+        Email, ExternalMetadataId, GoalId, ImportProfileId, ImportSessionId, MovieId, MovieTitle,
+        ReleaseYear, ReviewId, UserId, Username, WatchEventId, WebhookTokenId,
     },
 };
 
@@ -310,3 +318,462 @@ impl WatchlistRepository for InMemoryWatchlistRepository {
         Ok(self.store.lock().unwrap().contains_key(&key))
     }
 }
+
+// ── InMemoryGoalRepository ──────────────────────────────────────────────────
+
+pub struct InMemoryGoalRepository {
+    store: Mutex<HashMap<Uuid, Goal>>,
+    review_counts: Mutex<HashMap<(Uuid, u16), u32>>,
+}
+
+impl InMemoryGoalRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+            review_counts: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+
+    pub fn set_review_count(&self, user_id: Uuid, year: u16, count: u32) {
+        self.review_counts
+            .lock()
+            .unwrap()
+            .insert((user_id, year), count);
+    }
+}
+
+#[async_trait]
+impl GoalRepository for InMemoryGoalRepository {
+    async fn save(&self, goal: &Goal) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(goal.id().value(), goal.clone());
+        Ok(())
+    }
+
+    async fn update(&self, goal: &Goal) -> Result<(), DomainError> {
+        let mut store = self.store.lock().unwrap();
+        match store.entry(goal.id().value()) {
+            std::collections::hash_map::Entry::Occupied(mut e) => {
+                e.insert(goal.clone());
+                Ok(())
+            }
+            std::collections::hash_map::Entry::Vacant(_) => {
+                Err(DomainError::NotFound("goal".into()))
+            }
+        }
+    }
+
+    async fn delete(&self, id: &GoalId, _user_id: &UserId) -> Result<(), DomainError> {
+        self.store.lock().unwrap().remove(&id.value());
+        Ok(())
+    }
+
+    async fn find_by_user_and_year(
+        &self,
+        user_id: &UserId,
+        year: u16,
+    ) -> Result<Option<Goal>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .values()
+            .find(|g| g.user_id().value() == user_id.value() && g.year() == year)
+            .cloned())
+    }
+
+    async fn list_for_user(&self, user_id: &UserId) -> Result<Vec<Goal>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .values()
+            .filter(|g| g.user_id().value() == user_id.value())
+            .cloned()
+            .collect())
+    }
+
+    async fn count_reviews_in_year(&self, user_id: &UserId, year: u16) -> Result<u32, DomainError> {
+        let counts = self.review_counts.lock().unwrap();
+        Ok(counts.get(&(user_id.value(), year)).copied().unwrap_or(0))
+    }
+}
+
+// ── InMemoryUserSettingsRepository ──────────────────────────────────────────
+
+pub struct InMemoryUserSettingsRepository {
+    store: Mutex<HashMap<Uuid, UserSettings>>,
+}
+
+impl InMemoryUserSettingsRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl UserSettingsRepository for InMemoryUserSettingsRepository {
+    async fn get(&self, user_id: &UserId) -> Result<UserSettings, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .get(&user_id.value())
+            .cloned()
+            .unwrap_or_else(|| UserSettings::new(user_id.clone())))
+    }
+
+    async fn save(&self, settings: &UserSettings) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(settings.user_id().value(), settings.clone());
+        Ok(())
+    }
+}
+
+// ── InMemoryWebhookTokenRepository ──────────────────────────────────────────
+
+pub struct InMemoryWebhookTokenRepository {
+    store: Mutex<Vec<WebhookToken>>,
+}
+
+impl InMemoryWebhookTokenRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(Vec::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl WebhookTokenRepository for InMemoryWebhookTokenRepository {
+    async fn save(&self, token: &WebhookToken) -> Result<(), DomainError> {
+        self.store.lock().unwrap().push(token.clone());
+        Ok(())
+    }
+
+    async fn find_by_token_hash(&self, hash: &str) -> Result<Option<WebhookToken>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store.iter().find(|t| t.token_hash() == hash).cloned())
+    }
+
+    async fn list_by_user(&self, user_id: &UserId) -> Result<Vec<WebhookToken>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .iter()
+            .filter(|t| t.user_id().value() == user_id.value())
+            .cloned()
+            .collect())
+    }
+
+    async fn delete(&self, id: &WebhookTokenId, _user_id: &UserId) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .retain(|t| t.id().value() != id.value());
+        Ok(())
+    }
+
+    async fn touch_last_used(&self, _id: &WebhookTokenId) -> Result<(), DomainError> {
+        Ok(())
+    }
+}
+
+// ── InMemoryWatchEventRepository ────────────────────────────────────────────
+
+pub struct InMemoryWatchEventRepository {
+    store: Mutex<Vec<WatchEvent>>,
+}
+
+impl InMemoryWatchEventRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(Vec::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl WatchEventRepository for InMemoryWatchEventRepository {
+    async fn save(&self, event: &WatchEvent) -> Result<(), DomainError> {
+        self.store.lock().unwrap().push(event.clone());
+        Ok(())
+    }
+
+    async fn update_status(
+        &self,
+        _id: &WatchEventId,
+        _status: WatchEventStatus,
+    ) -> Result<(), DomainError> {
+        Ok(())
+    }
+
+    async fn list_pending(&self, user_id: &UserId) -> Result<Vec<WatchEvent>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .iter()
+            .filter(|e| {
+                e.user_id().value() == user_id.value() && *e.status() == WatchEventStatus::Pending
+            })
+            .cloned()
+            .collect())
+    }
+
+    async fn get_by_id(&self, id: &WatchEventId) -> Result<Option<WatchEvent>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store.iter().find(|e| e.id().value() == id.value()).cloned())
+    }
+
+    async fn get_by_ids(&self, ids: &[WatchEventId]) -> Result<Vec<WatchEvent>, DomainError> {
+        let id_vals: Vec<Uuid> = ids.iter().map(|id| id.value()).collect();
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .iter()
+            .filter(|e| id_vals.contains(&e.id().value()))
+            .cloned()
+            .collect())
+    }
+
+    async fn update_status_batch(
+        &self,
+        ids: &[WatchEventId],
+        _status: WatchEventStatus,
+    ) -> Result<u64, DomainError> {
+        Ok(ids.len() as u64)
+    }
+
+    async fn find_duplicate(
+        &self,
+        user_id: &UserId,
+        external_id: &str,
+        after: NaiveDateTime,
+    ) -> Result<bool, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store.iter().any(|e| {
+            e.user_id().value() == user_id.value()
+                && e.external_metadata_id() == Some(external_id)
+                && *e.watched_at() > after
+        }))
+    }
+
+    async fn delete_non_pending_older_than(
+        &self,
+        before: NaiveDateTime,
+    ) -> Result<u64, DomainError> {
+        let mut store = self.store.lock().unwrap();
+        let before_len = store.len();
+        store.retain(|e| *e.status() == WatchEventStatus::Pending || *e.created_at() >= before);
+        Ok((before_len - store.len()) as u64)
+    }
+}
+
+// ── InMemoryImportSessionRepository ─────────────────────────────────────────
+
+pub struct InMemoryImportSessionRepository {
+    store: Mutex<HashMap<Uuid, ImportSession>>,
+}
+
+impl InMemoryImportSessionRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl ImportSessionRepository for InMemoryImportSessionRepository {
+    async fn create(&self, session: &ImportSession) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(session.id.value(), session.clone());
+        Ok(())
+    }
+
+    async fn get(
+        &self,
+        id: &ImportSessionId,
+        user_id: &UserId,
+    ) -> Result<Option<ImportSession>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .get(&id.value())
+            .filter(|s| s.user_id.value() == user_id.value())
+            .cloned())
+    }
+
+    async fn update(&self, session: &ImportSession) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(session.id.value(), session.clone());
+        Ok(())
+    }
+
+    async fn delete(&self, id: &ImportSessionId) -> Result<(), DomainError> {
+        self.store.lock().unwrap().remove(&id.value());
+        Ok(())
+    }
+
+    async fn delete_expired(&self) -> Result<u64, DomainError> {
+        let mut store = self.store.lock().unwrap();
+        let now = chrono::Utc::now().naive_utc();
+        let before_len = store.len();
+        store.retain(|_, s| s.expires_at > now);
+        Ok((before_len - store.len()) as u64)
+    }
+
+    async fn delete_expired_for_user(&self, user_id: &UserId) -> Result<(), DomainError> {
+        let mut store = self.store.lock().unwrap();
+        let now = chrono::Utc::now().naive_utc();
+        store.retain(|_, s| !(s.user_id.value() == user_id.value() && s.expires_at <= now));
+        Ok(())
+    }
+}
+
+// ── InMemoryImportProfileRepository ─────────────────────────────────────────
+
+pub struct InMemoryImportProfileRepository {
+    store: Mutex<HashMap<Uuid, ImportProfile>>,
+}
+
+impl InMemoryImportProfileRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl ImportProfileRepository for InMemoryImportProfileRepository {
+    async fn save(&self, profile: &ImportProfile) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(profile.id.value(), profile.clone());
+        Ok(())
+    }
+
+    async fn list_for_user(&self, user_id: &UserId) -> Result<Vec<ImportProfile>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .values()
+            .filter(|p| p.user_id.value() == user_id.value())
+            .cloned()
+            .collect())
+    }
+
+    async fn get(
+        &self,
+        id: &ImportProfileId,
+        user_id: &UserId,
+    ) -> Result<Option<ImportProfile>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store
+            .get(&id.value())
+            .filter(|p| p.user_id.value() == user_id.value())
+            .cloned())
+    }
+
+    async fn delete(&self, id: &ImportProfileId) -> Result<(), DomainError> {
+        self.store.lock().unwrap().remove(&id.value());
+        Ok(())
+    }
+}
+
+// ── InMemoryMovieProfileRepository ──────────────────────────────────────────
+
+pub struct InMemoryMovieProfileRepository {
+    store: Mutex<HashMap<Uuid, MovieProfile>>,
+}
+
+impl InMemoryMovieProfileRepository {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl MovieProfileRepository for InMemoryMovieProfileRepository {
+    async fn upsert(&self, profile: &MovieProfile) -> Result<(), DomainError> {
+        self.store
+            .lock()
+            .unwrap()
+            .insert(profile.movie_id.value(), profile.clone());
+        Ok(())
+    }
+
+    async fn get_by_movie_id(&self, id: &MovieId) -> Result<Option<MovieProfile>, DomainError> {
+        Ok(self.store.lock().unwrap().get(&id.value()).cloned())
+    }
+
+    async fn list_stale(&self) -> Result<Vec<(MovieId, String)>, DomainError> {
+        Ok(vec![])
+    }
+}
+
+// ── InMemoryProfileFieldsRepo ───────────────────────────────────────────────
+
+pub struct InMemoryProfileFieldsRepo {
+    store: Mutex<HashMap<Uuid, Vec<ProfileField>>>,
+}
+
+impl InMemoryProfileFieldsRepo {
+    pub fn new() -> Arc<Self> {
+        Arc::new(Self {
+            store: Mutex::new(HashMap::new()),
+        })
+    }
+
+    pub fn count(&self) -> usize {
+        self.store.lock().unwrap().len()
+    }
+}
+
+#[async_trait]
+impl UserProfileFieldsRepository for InMemoryProfileFieldsRepo {
+    async fn get_fields(&self, user_id: &UserId) -> Result<Vec<ProfileField>, DomainError> {
+        let store = self.store.lock().unwrap();
+        Ok(store.get(&user_id.value()).cloned().unwrap_or_default())
+    }
+
+    async fn set_fields(
+        &self,
+        user_id: &UserId,
+        fields: Vec<ProfileField>,
+    ) -> Result<(), DomainError> {
+        self.store.lock().unwrap().insert(user_id.value(), fields);
+        Ok(())
+    }
+}