diff --git a/back/src/Kyoo.Abstractions/Module.cs b/back/src/Kyoo.Abstractions/Module.cs
index 1abfd1e9..373fcd8c 100644
--- a/back/src/Kyoo.Abstractions/Module.cs
+++ b/back/src/Kyoo.Abstractions/Module.cs
@@ -42,6 +42,7 @@ namespace Kyoo.Abstractions
 			where T : IBaseRepository
 		{
 			return builder.RegisterType<T>()
+				.AsSelf()
 				.As<IBaseRepository>()
 				.As(Utility.GetGenericDefinition(typeof(T), typeof(IRepository<>))!)
 				.InstancePerLifetimeScope();
@@ -62,7 +63,7 @@ namespace Kyoo.Abstractions
 			where T : notnull
 			where T2 : IBaseRepository, T
 		{
-			return builder.RegisterRepository<T2>().As<T>();
+			return builder.RegisterRepository<T2>().AsSelf().As<T>();
 		}
 	}
 }
diff --git a/back/src/Kyoo.Core/Controllers/Repositories/CollectionRepository.cs b/back/src/Kyoo.Core/Controllers/Repositories/CollectionRepository.cs
index a8fe9241..6d219148 100644
--- a/back/src/Kyoo.Core/Controllers/Repositories/CollectionRepository.cs
+++ b/back/src/Kyoo.Core/Controllers/Repositories/CollectionRepository.cs
@@ -19,6 +19,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Linq.Expressions;
 using System.Threading.Tasks;
 using Kyoo.Abstractions.Controllers;
 using Kyoo.Abstractions.Models;
@@ -81,6 +82,18 @@ namespace Kyoo.Core.Controllers
 				throw new ArgumentException("The collection's name must be set and not empty");
 		}
 
+		public async Task AddMovie(int id, int movieId)
+		{
+			_database.AddLinks<Collection, Movie>(id, movieId);
+			await _database.SaveChangesAsync();
+		}
+
+		public async Task AddShow(int id, int showId)
+		{
+			_database.AddLinks<Collection, Show>(id, showId);
+			await _database.SaveChangesAsync();
+		}
+
 		/// <inheritdoc />
 		public override async Task Delete(Collection obj)
 		{
diff --git a/back/src/Kyoo.Core/Views/Resources/CollectionApi.cs b/back/src/Kyoo.Core/Views/Resources/CollectionApi.cs
index 137a5797..497df34a 100644
--- a/back/src/Kyoo.Core/Views/Resources/CollectionApi.cs
+++ b/back/src/Kyoo.Core/Views/Resources/CollectionApi.cs
@@ -24,6 +24,7 @@ using Kyoo.Abstractions.Models;
 using Kyoo.Abstractions.Models.Attributes;
 using Kyoo.Abstractions.Models.Permissions;
 using Kyoo.Abstractions.Models.Utils;
+using Kyoo.Core.Controllers;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
 using static Kyoo.Abstractions.Models.Utils.Constants;
@@ -40,23 +41,78 @@ namespace Kyoo.Core.Api
 	[ApiDefinition("Collections", Group = ResourcesGroup)]
 	public class CollectionApi : CrudThumbsApi<Collection>
 	{
-		/// <summary>
-		/// The library manager used to modify or retrieve information about the data store.
-		/// </summary>
 		private readonly ILibraryManager _libraryManager;
+		private readonly CollectionRepository _collections;
 
-		/// <summary>
-		/// Create a new <see cref="CollectionApi"/>.
-		/// </summary>
-		/// <param name="libraryManager">
-		/// The library manager used to modify or retrieve information about the data store.
-		/// </param>
-		/// <param name="thumbs">The thumbnail manager used to retrieve images paths.</param>
 		public CollectionApi(ILibraryManager libraryManager,
+			CollectionRepository collections,
 			IThumbnailsManager thumbs)
 			: base(libraryManager.Collections, thumbs)
 		{
 			_libraryManager = libraryManager;
+			_collections = collections;
+		}
+
+		/// <summary>
+		/// Add a movie
+		/// </summary>
+		/// <remarks>
+		/// Add a movie in the collection.
+		/// </remarks>
+		/// <param name="identifier">The ID or slug of the <see cref="Collection"/>.</param>
+		/// <param name="movie">The ID or slug of the <see cref="Movie"/> to add.</param>
+		/// <returns>Nothing if successful.</returns>
+		/// <response code="404">No collection or movie with the given ID could be found.</response>
+		/// <response code="409">The specified movie is already in this collection.</response>
+		[HttpPut("{identifier:id}/movies/{movie:id}")]
+		[HttpPut("{identifier:id}/movie/{movie:id}", Order = AlternativeRoute)]
+		[PartialPermission(Kind.Write)]
+		[ProducesResponseType(StatusCodes.Status204NoContent)]
+		[ProducesResponseType(StatusCodes.Status404NotFound)]
+		[ProducesResponseType(StatusCodes.Status409Conflict)]
+		public async Task<ActionResult> AddMovie(Identifier identifier, Identifier movie)
+		{
+			int collectionId = await identifier.Match(
+				async id => (await _libraryManager.Collections.Get(id)).Id,
+				async slug => (await _libraryManager.Collections.Get(slug)).Id
+			);
+			int movieId = await movie.Match(
+				async id => (await _libraryManager.Movies.Get(id)).Id,
+				async slug => (await _libraryManager.Movies.Get(slug)).Id
+			);
+			await _collections.AddMovie(collectionId, movieId);
+			return NoContent();
+		}
+
+		/// <summary>
+		/// Add a show
+		/// </summary>
+		/// <remarks>
+		/// Add a show in the collection.
+		/// </remarks>
+		/// <param name="identifier">The ID or slug of the <see cref="Collection"/>.</param>
+		/// <param name="show">The ID or slug of the <see cref="Show"/> to add.</param>
+		/// <returns>Nothing if successful.</returns>
+		/// <response code="404">No collection or show with the given ID could be found.</response>
+		/// <response code="409">The specified show is already in this collection.</response>
+		[HttpPut("{identifier:id}/shows/{show:id}")]
+		[HttpPut("{identifier:id}/show/{show:id}", Order = AlternativeRoute)]
+		[PartialPermission(Kind.Write)]
+		[ProducesResponseType(StatusCodes.Status204NoContent)]
+		[ProducesResponseType(StatusCodes.Status404NotFound)]
+		[ProducesResponseType(StatusCodes.Status409Conflict)]
+		public async Task<ActionResult> AddShow(Identifier identifier, Identifier show)
+		{
+			int collectionId = await identifier.Match(
+				async id => (await _libraryManager.Collections.Get(id)).Id,
+				async slug => (await _libraryManager.Collections.Get(slug)).Id
+			);
+			int showId = await show.Match(
+				async id => (await _libraryManager.Shows.Get(id)).Id,
+				async slug => (await _libraryManager.Shows.Get(slug)).Id
+			);
+			await _collections.AddShow(collectionId, showId);
+			return NoContent();
 		}
 
 		/// <summary>
@@ -83,11 +139,11 @@ namespace Kyoo.Core.Api
 			[FromQuery] Sort<Show> sortBy,
 			[FromQuery] Dictionary<string, string> where,
 			[FromQuery] Pagination pagination,
-			[FromQuery] Include<Show> fields)
+			[FromQuery] Include<Show>? fields)
 		{
 			ICollection<Show> resources = await _libraryManager.Shows.GetAll(
 				ApiHelper.ParseWhere(where, identifier.IsContainedIn<Show, Collection>(x => x.Collections!)),
-				sortBy,
+				sortBy ?? new Sort<Show>.By(x => x.StartAir),
 				pagination,
 				fields
 			);
diff --git a/back/src/Kyoo.Postgresql/DatabaseContext.cs b/back/src/Kyoo.Postgresql/DatabaseContext.cs
index 4399841d..9509da6b 100644
--- a/back/src/Kyoo.Postgresql/DatabaseContext.cs
+++ b/back/src/Kyoo.Postgresql/DatabaseContext.cs
@@ -116,13 +116,12 @@ namespace Kyoo.Postgresql
 		/// <param name="second">The ID of the second resource.</param>
 		/// <typeparam name="T1">The first resource type of the relation. It is the owner of the second</typeparam>
 		/// <typeparam name="T2">The second resource type of the relation. It is the contained resource.</typeparam>
-		/// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
-		public async Task AddLinks<T1, T2>(int first, int second)
+		public void AddLinks<T1, T2>(int first, int second)
 			where T1 : class, IResource
 			where T2 : class, IResource
 		{
-			await Set<Dictionary<string, object>>(LinkName<T1, T2>())
-				.AddAsync(new Dictionary<string, object>
+			Set<Dictionary<string, object>>(LinkName<T1, T2>())
+				.Add(new Dictionary<string, object>
 				{
 					[LinkNameFk<T1>()] = first,
 					[LinkNameFk<T2>()] = second