diff --git a/dotnet/AipsCore/AipsCore.csproj b/dotnet/AipsCore/AipsCore.csproj
index 0e42146..3f0347f 100644
--- a/dotnet/AipsCore/AipsCore.csproj
+++ b/dotnet/AipsCore/AipsCore.csproj
@@ -6,4 +6,8 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <PackageReference Include="Microsoft.EntityFrameworkCore" Version="10.0.2" />
+    </ItemGroup>
+
 </Project>
diff --git a/dotnet/AipsCore/Application/Models/User/Command/CreateUserCommand.cs b/dotnet/AipsCore/Application/Models/User/Command/CreateUserCommand.cs
new file mode 100644
index 0000000..fdb6f36
--- /dev/null
+++ b/dotnet/AipsCore/Application/Models/User/Command/CreateUserCommand.cs
@@ -0,0 +1,6 @@
+using AipsCore.Application.Abstract.Command;
+using AipsCore.Domain.Models.User.ValueObjects;
+
+namespace AipsCore.Application.Models.User.Command;
+
+public record CreateUserCommand(string Username, string Email) : ICommand<UserId>, ICommand;
\ No newline at end of file
diff --git a/dotnet/AipsCore/Application/Models/User/Command/Handler/CreateUserCommandHandler.cs b/dotnet/AipsCore/Application/Models/User/Command/Handler/CreateUserCommandHandler.cs
new file mode 100644
index 0000000..eff3150
--- /dev/null
+++ b/dotnet/AipsCore/Application/Models/User/Command/Handler/CreateUserCommandHandler.cs
@@ -0,0 +1,23 @@
+using AipsCore.Application.Abstract.Command;
+using AipsCore.Domain.Common.ValueObjects;
+using AipsCore.Domain.Models.User.External;
+using AipsCore.Domain.Models.User.ValueObjects;
+
+namespace AipsCore.Application.Models.User.Command.Handler;
+
+public class CreateUserCommandHandler : ICommandHandler<CreateUserCommand>
+{
+    private readonly IUserRepository _userRepository;
+
+    public CreateUserCommandHandler(IUserRepository userRepository)
+    {
+        _userRepository = userRepository;
+    }
+    
+    public async Task Handle(CreateUserCommand command, CancellationToken cancellationToken = default)
+    {
+        var user = Domain.Models.User.User.Create(command.Email, command.Username); 
+        
+        await _userRepository.Save(user, cancellationToken);
+    }
+}
\ No newline at end of file
diff --git a/dotnet/AipsCore/Domain/Common/ValueObjects/DomainId.cs b/dotnet/AipsCore/Domain/Common/ValueObjects/DomainId.cs
index 6f76d85..c638377 100644
--- a/dotnet/AipsCore/Domain/Common/ValueObjects/DomainId.cs
+++ b/dotnet/AipsCore/Domain/Common/ValueObjects/DomainId.cs
@@ -2,6 +2,7 @@
 using AipsCore.Domain.Abstract.Rule;
 using AipsCore.Domain.Abstract.ValueObject;
 using AipsCore.Domain.Common.Validation;
+using AipsCore.Domain.Common.Validation.Rules;
 
 namespace AipsCore.Domain.Common.ValueObjects;
 
@@ -17,6 +18,8 @@ public record DomainId : AbstractValueObject
 
     protected override ICollection<IRule> GetValidationRules()
     {
-        return [];
+        return [
+            new MinLengthRule(IdValue, 5)
+        ];
     }
 }
\ No newline at end of file
diff --git a/dotnet/AipsCore/Domain/Models/User/External/IUserRepository.cs b/dotnet/AipsCore/Domain/Models/User/External/IUserRepository.cs
new file mode 100644
index 0000000..c776a74
--- /dev/null
+++ b/dotnet/AipsCore/Domain/Models/User/External/IUserRepository.cs
@@ -0,0 +1,9 @@
+using AipsCore.Domain.Models.User.ValueObjects;
+
+namespace AipsCore.Domain.Models.User.External;
+
+public interface IUserRepository
+{
+    Task<User?> Get(UserId userId, CancellationToken cancellationToken = default);
+    Task Save(User user, CancellationToken cancellationToken = default);
+}
\ No newline at end of file
diff --git a/dotnet/AipsCore/Domain/Models/User/User.cs b/dotnet/AipsCore/Domain/Models/User/User.cs
index 1ca404c..416f102 100644
--- a/dotnet/AipsCore/Domain/Models/User/User.cs
+++ b/dotnet/AipsCore/Domain/Models/User/User.cs
@@ -15,4 +15,19 @@ public class User
         Email = email;
         Username = username;
     }
+    
+    public static User Create(string id, string email, string username)
+    {
+        var userIdVo = new UserId(id);
+        var usernameVo = new Username(username);
+        var emailVo = new Email(email);
+        return new User( userIdVo, emailVo, usernameVo);
+    }
+    
+    public static User Create(string email, string username)
+    {
+        var usernameVo = new Username(username);
+        var emailVo = new Email(email);
+        return new User( UserId.Any(), emailVo, usernameVo);
+    }
 }
\ No newline at end of file
diff --git a/dotnet/AipsCore/Domain/Models/User/ValueObjects/UserId.cs b/dotnet/AipsCore/Domain/Models/User/ValueObjects/UserId.cs
index 022011e..cfc341c 100644
--- a/dotnet/AipsCore/Domain/Models/User/ValueObjects/UserId.cs
+++ b/dotnet/AipsCore/Domain/Models/User/ValueObjects/UserId.cs
@@ -2,4 +2,7 @@
 
 namespace AipsCore.Domain.Models.User.ValueObjects;
 
-public record UserId(string IdValue) : DomainId(IdValue);
\ No newline at end of file
+public record UserId(string IdValue) : DomainId(IdValue)
+{
+    public static UserId Any() => new(Guid.NewGuid().ToString());
+}
\ No newline at end of file
diff --git a/dotnet/AipsCore/Infrastructure/Db/AipsDbContext.cs b/dotnet/AipsCore/Infrastructure/Db/AipsDbContext.cs
index ab85fb3..b39a190 100644
--- a/dotnet/AipsCore/Infrastructure/Db/AipsDbContext.cs
+++ b/dotnet/AipsCore/Infrastructure/Db/AipsDbContext.cs
@@ -1,6 +1,9 @@
-namespace AipsCore.Infrastructure.Db;
+using AipsCore.Infrastructure.Entities;
+using Microsoft.EntityFrameworkCore;
 
-public class AipsDbContext
+namespace AipsCore.Infrastructure.Db;
+
+public class AipsDbContext : DbContext
 {
-    
+    public DbSet<User> Users { get; set; }
 }
\ No newline at end of file
diff --git a/dotnet/AipsCore/Infrastructure/Entities/User.cs b/dotnet/AipsCore/Infrastructure/Entities/User.cs
new file mode 100644
index 0000000..202f2ca
--- /dev/null
+++ b/dotnet/AipsCore/Infrastructure/Entities/User.cs
@@ -0,0 +1,12 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace AipsCore.Infrastructure.Entities;
+
+
+public class User
+{
+    [Key]
+    public Guid Id { get; set; }
+    [Required] [MaxLength(255)] public string Username { get; set; } = null!;
+    [Required] [MaxLength(255)] public string Email { get; set; } = null!;
+}
\ No newline at end of file
diff --git a/dotnet/AipsCore/Infrastructure/Repositories/UserRepository.cs b/dotnet/AipsCore/Infrastructure/Repositories/UserRepository.cs
new file mode 100644
index 0000000..8314ac6
--- /dev/null
+++ b/dotnet/AipsCore/Infrastructure/Repositories/UserRepository.cs
@@ -0,0 +1,53 @@
+using AipsCore.Domain.Common.ValueObjects;
+using AipsCore.Domain.Models.User;
+using AipsCore.Domain.Models.User.External;
+using AipsCore.Domain.Models.User.ValueObjects;
+using AipsCore.Infrastructure.Db;
+
+namespace AipsCore.Infrastructure.Repositories;
+
+public class UserRepository : IUserRepository
+{
+    private readonly AipsDbContext _context;
+
+    public UserRepository(AipsDbContext context)
+    {
+        _context = context;
+    }
+    
+    public async Task<User?> Get(UserId userId, CancellationToken cancellationToken = default)
+    {
+        var userEntity = await _context.Users.FindAsync([new Guid(userId.IdValue), cancellationToken], cancellationToken: cancellationToken);
+
+        if (userEntity is null) return null;
+        
+        return User.Create(
+            userEntity.Id.ToString(),
+            userEntity.Email,
+            userEntity.Username);
+    }
+
+    public async Task Save(User user, CancellationToken cancellationToken = default)
+    {
+        var userEntity = await _context.Users.FindAsync([new Guid(user.Id.IdValue), cancellationToken], cancellationToken: cancellationToken);
+
+        if (userEntity is not null)
+        {
+            userEntity.Email = user.Email.EmailValue;
+            userEntity.Username = user.Username.UsernameValue;
+            
+            _context.Users.Update(userEntity);
+        }
+        else
+        {
+            userEntity = new Entities.User()
+            {
+                Id = new Guid(user.Id.IdValue),
+                Email = user.Email.EmailValue,
+                Username = user.Username.UsernameValue,
+            };
+            
+            _context.Users.Add(userEntity);
+        }
+    }
+}
\ No newline at end of file