diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..16ac8e3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+.vscode
+appsettings.Development.json
+*.json
+bin
+obj
diff --git a/Controllers/ContactManagement.cs b/Controllers/ContactManagement.cs
new file mode 100644
index 0000000..36f0630
--- /dev/null
+++ b/Controllers/ContactManagement.cs
@@ -0,0 +1,67 @@
+using TextSender_API.Models;
+
+namespace TextSender_API.Controllers;
+
+public class ContactManagement
+{
+    #region Fields
+    private IConfiguration _config;
+    #endregion
+
+
+    #region Constructors
+    public ContactManagement(IConfiguration config)
+    {
+        this._config = config;
+    }
+    #endregion
+
+
+    #region Methods
+    // Queues the contact file to be processed latter
+    public ContactCreationQueue QueueContact(IFormFile file)
+    {
+        var queue = new ContactCreationQueue();
+        queue.Processed = false;
+        var directory = this._config["Paths:ContactQueueDirectory"];
+
+        if (directory!.ElementAt(directory!.Length - 1) != '/')
+        {
+            directory.Append('/');
+        }
+
+        if (!System.IO.Directory.Exists(directory))
+        {
+            queue.Status = "Missing directory";
+            // Directory does not exist
+            return queue;
+        }
+
+        var length = 16;
+        var chars = "ABCDEF0123456789";
+        var random = new Random();
+        var filename = new string(Enumerable.Repeat(chars, length).Select(s =>
+            s[random.Next(s.Length)]).ToArray());
+        var extension = ".txt";
+
+        var contactPath = $"{directory}/{filename}{extension}";
+        queue.Filepath = contactPath;
+
+        if (System.IO.File.Exists(contactPath))
+        {
+            // Already exists
+            queue.Status = "File exists";
+            return queue;
+        }
+
+        queue.Status = "Created";
+
+        using (var filestream = new FileStream(contactPath, FileMode.Create))
+        {
+            file.CopyTo(filestream);
+        }
+
+        return queue;
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/Controllers/ContactQueueCreationController.cs b/Controllers/ContactQueueCreationController.cs
new file mode 100644
index 0000000..4f9ae4a
--- /dev/null
+++ b/Controllers/ContactQueueCreationController.cs
@@ -0,0 +1,88 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Newtonsoft.Json;
+
+using TextSender_API.Models;
+using TextSender_API.Repositories;
+
+namespace TextSender_API.Controllers;
+
+[Authorize]
+[ApiController]
+[Route("api/v1/contact/queue")]
+public class ContactQueueCreationController : ControllerBase
+{
+    #region Fields
+    private IConfiguration _config;
+    private readonly ILogger<ContactQueueCreationController> _logger;
+    #endregion
+
+
+    #region Constructors        
+
+    public ContactQueueCreationController(ILogger<ContactQueueCreationController> logger, IConfiguration config)
+    {
+        this._logger = logger;
+        this._config = config;
+    }
+    #endregion
+
+    #region Methods
+    [HttpPost("upload"), DisableRequestSizeLimit]
+    public IActionResult Upload([FromForm(Name = "file")] List<IFormFile> contactFile,
+        [FromForm(Name = "user_id")] string userID)
+    {
+        // Save the file on the filesystem to be processed by a separate
+        // system
+        var response = new CreateQueueResponse();
+        var connString = this._config.GetConnectionString("MongoDBURI");
+        var userRepo =  new UsersRepository(connString!);
+        var queueRepo = new ContactCreationQueueRepository(connString!);
+
+        try
+        {
+            var ctMgr = new ContactManagement(this._config);
+            var user = userRepo.Exists(userID);
+
+            if (!user.Item1)
+            {
+                return NotFound(response);
+            }
+
+            foreach (var file in contactFile)
+            {
+                var queue = ctMgr.QueueContact(file);
+                queue.UserId = user.Item2.Id;
+                queue.DateCreated = DateTime.Now;
+                queueRepo.Create(queue);
+
+                response.Data.Add(queue);
+            }
+        }
+        catch (Exception ex)
+        {
+            this._logger.LogError($"An error occurred: {ex.Message}");
+        }
+
+        return Ok(response);
+    }
+    #endregion
+
+
+    #region Responses
+    public class CreateQueueResponse
+    {
+        #region Properties
+        [JsonProperty("data")]
+        public List<ContactCreationQueue> Data { get; set; }
+        #endregion
+
+        #region Constructors
+        public CreateQueueResponse()
+        {
+            this.Data = new List<ContactCreationQueue>();
+        }
+        #endregion
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/Controllers/ContactsController.cs b/Controllers/ContactsController.cs
new file mode 100644
index 0000000..9d492d8
--- /dev/null
+++ b/Controllers/ContactsController.cs
@@ -0,0 +1,94 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Newtonsoft.Json;
+
+using TextSender_API.Models;
+using TextSender_API.Repositories;
+
+namespace TextSender_API.Controllers;
+
+[Authorize]
+[ApiController]
+[Route("api/v1/contact")]
+public class ContactsController : ControllerBase
+{
+    #region Fields
+    private IConfiguration _config;
+    private readonly ILogger<ContactsController> _logger;
+    #endregion
+
+
+    #region Constructors        
+
+    public ContactsController(ILogger<ContactsController> logger, IConfiguration config)
+    {
+        this._logger = logger;
+        this._config = config;
+    }
+    #endregion
+
+    #region Methods
+    [HttpPost("new"), DisableRequestSizeLimit]
+    public IActionResult CreateContact([FromBody] Contact contact)
+    {
+        var response = new CreateContactResponse();
+        var connString = this._config.GetConnectionString("MongoDBURI");
+        var userRepo = new UsersRepository(connString!);
+        var contactsRepo = new ContactsRepository(connString!);
+
+        try
+        {
+            var contacts = contactsRepo.RetrieveAll();
+            var users = userRepo.RetrieveAllUsers();
+
+            if (users.Count() == 0)
+            {
+                return BadRequest(response);
+            }
+
+            if (contacts.Count() > 0)
+            {
+                if (contacts.Exists(c => c.PhoneNumber!.Equals(contact.PhoneNumber)) ||
+                    string.IsNullOrEmpty(contact.UserID))
+                {
+                    // The Contact already exists
+                    return BadRequest(response);
+                }
+            }
+
+            if (!userRepo.Exists(contact.UserID!).Item1)
+            {
+                return BadRequest(response);
+            }
+
+            contact.DateCreated = DateTime.Now;
+            contactsRepo.Create(contact);
+            response.Data.Add(contact);
+        }
+        catch (Exception ex)
+        {
+            this._logger.LogError($"An error occurred: {ex.Message}");
+        }
+
+        return Ok(response);
+    }
+    #endregion
+
+
+    #region Responses
+    public class CreateContactResponse
+    {
+        #region Properties
+        [JsonProperty("data")]
+        public List<Contact> Data { get; set; }
+        #endregion
+
+        #region Constructors
+        public CreateContactResponse()
+        {
+            this.Data = new List<Contact>();
+        }
+        #endregion
+    }
+    #endregion
+}
diff --git a/Controllers/PasswordVerification.cs b/Controllers/PasswordVerification.cs
new file mode 100644
index 0000000..0eac000
--- /dev/null
+++ b/Controllers/PasswordVerification.cs
@@ -0,0 +1,64 @@
+using System.Security.Cryptography;
+using System.Text;
+
+using TextSender_API.Models;
+using TextSender_API.Repositories;
+
+namespace TextSender_API.Controllers;
+
+public class PasswordVerification
+{
+    #region Fiends
+    private UsersRepository _userRepo;
+    private SaltRepository _saltRepo;
+    private int _keySize = 64;
+    private int _iterations = 350000;
+    #endregion
+
+    #region Constructors
+    public PasswordVerification(UsersRepository userRepo, SaltRepository saltRepo)
+    {
+        this._userRepo = userRepo;
+        this._saltRepo = saltRepo;
+    }
+    #endregion
+
+    #region Methods
+    public bool VerifyPassword(User user, string password)
+    {
+        var salt = this._saltRepo.Retrieve(user.Id!);
+        var hashedPassword = this.HashPassword(user, salt, password);
+
+        return hashedPassword.Equals(user.Password);
+    }
+    public Salt CreateSalt(User user)
+    {
+        var salt = new Salt();
+        salt.Key = RandomNumberGenerator.GetBytes(this._keySize);
+
+        return salt;
+    }
+
+    public string HashPassword(User user, Salt salt, string password = "")
+    {
+        var hashAlgorithm = HashAlgorithmName.SHA512;
+        var dbHashedPassword = user.Password;
+
+        if (!string.IsNullOrEmpty(password))
+        {
+            user.Password = password;
+        }
+
+        var hash = Rfc2898DeriveBytes.Pbkdf2(
+            Encoding.UTF8.GetBytes(user.Password!),
+            salt.Key!,
+            this._iterations,
+            hashAlgorithm,
+            this._keySize);
+
+        user.Password = dbHashedPassword;
+
+        return Convert.ToHexString(hash);
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/Controllers/UsersController.cs b/Controllers/UsersController.cs
new file mode 100644
index 0000000..c90b7aa
--- /dev/null
+++ b/Controllers/UsersController.cs
@@ -0,0 +1,228 @@
+using System.IdentityModel.Tokens;
+using System.IdentityModel.Tokens.Jwt;
+using System.Linq;
+using System.Security.Claims;
+using System.Security.Cryptography;
+using System.Text;
+using System.Threading.Tasks;
+
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.IdentityModel.Tokens;
+using Newtonsoft.Json;
+
+using TextSender_API.Models;
+using TextSender_API.Repositories;
+
+namespace TextSender_API.Controllers;
+
+[ApiController]
+[Route("api/v1/user")]
+public class UsersController : ControllerBase
+{
+    #region Fields
+    private readonly ILogger<UsersController> _logger;
+    private IConfiguration _config;
+    #endregion
+
+
+    #region Constructors        
+
+    public UsersController(ILogger<UsersController> logger, IConfiguration config)
+    {
+        this._logger = logger;
+        this._config = config;
+    }
+    #endregion
+
+    #region Methods
+    private string AllScopes()
+    {
+        var allScopes = new List<String>()
+        {
+            "create:contact"
+        };
+
+        var scopes = string.Empty;
+
+        for (var i = 0; i < allScopes.Count; i++)
+        {
+            if (i == allScopes.Count - 1)
+            {
+                scopes += allScopes[i];
+            }
+            else
+            {
+                scopes += allScopes[i] + " ";
+            }
+        }
+
+        return scopes;
+    }
+
+    private List<Claim> Payload()
+    {
+        var expLimit = 30;
+        var currentDate = DateTime.Now;
+        var expiredDate = currentDate.AddMinutes(expLimit);
+        var issued = Math.Floor((currentDate - DateTime.UnixEpoch).TotalSeconds);
+        var expires = Math.Floor((expiredDate - DateTime.UnixEpoch).TotalSeconds);
+        var issuer = this._config["JWT:Issuer"];
+        var audience = this._config["JWT:Audience"];
+        var subject = this._config["JWT:Subject"];
+
+        var claim = new List<System.Security.Claims.Claim>()
+        {
+            new System.Security.Claims.Claim("scope", AllScopes(), "string"),
+            new System.Security.Claims.Claim(JwtRegisteredClaimNames.Exp, expiredDate.ToString(), "string"),
+            new System.Security.Claims.Claim(JwtRegisteredClaimNames.Aud, audience!),
+            new System.Security.Claims.Claim(JwtRegisteredClaimNames.Iss, issuer!),
+            new Claim(JwtRegisteredClaimNames.Sub, subject!)
+        };
+
+        return claim;
+    }
+
+    [HttpPost("login")]
+    public IActionResult Login([FromBody] User userRequest)
+    {
+        var response = new LoginResponse();
+
+        try
+        {
+            var connString = this._config.GetConnectionString("MongoDBURI");
+            var userRepo = new UsersRepository(connString!);
+            var saltRepo = new SaltRepository(connString!);
+            var pwdVerify = new PasswordVerification(userRepo, saltRepo);
+            var result = userRepo.Exists(userRequest);
+
+            if (result.Item1 && pwdVerify.VerifyPassword(result.Item2, userRequest.Password!))
+            {
+                var user = result.Item2;
+                var token = new Token();
+                token.Issued = DateTime.Now;
+                token.UserId = user.Id;
+                token.TokenType = "JWT";
+
+                var payload = Payload();
+                payload.Add(new System.Security.Claims.Claim("user_id", user.Id!, ClaimValueTypes.String));
+
+                var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(this._config["JWT:Secret"]!));
+                var signIn = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
+
+                var tok = new JwtSecurityToken(
+                    this._config["JWT:Issuer"],
+                    this._config["JWT:Audience"],
+                    payload,
+                    expires: DateTime.UtcNow.AddMinutes(30),
+                    signingCredentials: signIn);
+
+                token.AccessToken = new JwtSecurityTokenHandler().WriteToken(tok);
+
+                var expClaim = payload.FirstOrDefault(cl =>
+                {
+                    return cl.Type.Equals("exp");
+                });
+
+                if (expClaim != null)
+                {
+                    var expiredDate = DateTime.Parse(expClaim!.Value);
+                    var exp = Math.Floor((expiredDate - DateTime.UnixEpoch).TotalSeconds);
+                }
+
+                response.Data.Add(token);
+                Ok(response);
+            }
+            else
+            {
+                return NotFound(response);
+            }
+        }
+        catch (Exception ex)
+        {
+            this._logger.LogError($"An error occurred: {ex.Message}");
+        }
+
+        return Ok(response);
+    }
+
+    [HttpPost("register"), DisableRequestSizeLimit]
+    public IActionResult Upload([FromBody] User userRequest)
+    {
+        var response = new RegisterUserResponse();
+
+        try
+        {
+            var connString = this._config.GetConnectionString("MongoDBURI");
+            var userRepo = new UsersRepository(connString!);
+            var saltRepo = new SaltRepository(connString!);
+            var allUsers = userRepo.RetrieveAllUsers();
+            var result = allUsers.Exists(ea => ea.Username!.Equals(userRequest.Username));
+
+            if (!result)
+            {
+                var pwdVerify = new PasswordVerification(userRepo, saltRepo);
+                var salt = pwdVerify.CreateSalt(userRequest);
+                var hashedPassword = pwdVerify.HashPassword(userRequest, salt);
+
+                this._logger.LogInformation("Creating user");
+                userRequest.Password = hashedPassword;
+                userRequest.DateCreated = DateTime.Now;
+                userRepo.CreateUser(userRequest);
+
+                response.Data.Add(userRequest);
+
+                salt.UserId = userRequest.Id;
+                saltRepo.Create(salt);
+            }
+            else
+            {
+                this._logger.LogInformation("User already exists");
+            }
+        }
+        catch (Exception ex)
+        {
+            this._logger.LogError($"An error occurred: {ex.Message}");
+        }
+
+        return Ok(response);
+    }
+    #endregion
+
+    #region Responses
+    public class LoginResponse
+    {
+        #region Properties
+        [JsonProperty("data")]
+        public List<Token> Data { get; set; }
+        #endregion
+
+        #region Constructors
+        public LoginResponse()
+        {
+            this.Data = new List<Token>();
+        }
+        #endregion
+
+        #region Methods
+        #endregion
+    }
+
+    public class RegisterUserResponse
+    {
+        #region Properties
+        [JsonProperty("data")]
+        public List<User> Data { get; set; }
+        #endregion
+
+        #region Constructors
+        public RegisterUserResponse()
+        {
+            this.Data = new List<User>();
+        }
+        #endregion
+
+        #region Methods
+        #endregion
+    }
+    #endregion
+}
diff --git a/Models/Contact.cs b/Models/Contact.cs
new file mode 100644
index 0000000..72da9a0
--- /dev/null
+++ b/Models/Contact.cs
@@ -0,0 +1,53 @@
+using System;
+
+using MongoDB.Bson;
+using MongoDB.Bson.Serialization.Attributes;
+using Newtonsoft.Json;
+
+namespace TextSender_API.Models;
+
+public class Contact
+{
+#region Properties
+    [BsonId]
+    [BsonRepresentation(BsonType.ObjectId)]
+    [JsonProperty("id")]
+    public string? Id { get; set; }
+    [BsonElement("firstname")]
+    [JsonProperty("firstname")]
+    public string? Firstname { get; set; }
+    [BsonElement("lastname")]
+    [JsonProperty("lastname")]
+    public string? Lastname { get; set; }
+    [BsonElement("phonenumber")]
+    [JsonProperty("phonenumber")]
+    public string? PhoneNumber { get; set; }
+    [BsonElement("date_created")]
+    [JsonProperty("date_created")]
+    public DateTime DateCreated { get; set; }
+    // [BsonRepresentation(BsonType.ObjectId)]
+    [BsonElement("user_id")]
+    [JsonProperty("user_id")]
+    public string? UserID  { get; set; }
+#endregion
+}
+
+
+public class ContactCreationQueue
+{
+    #region Properties
+    [BsonId]
+    [BsonRepresentation(BsonType.ObjectId)]
+    public string? Id { get; set; }
+    [BsonElement("filepath")]
+    public string? Filepath { get; set; }
+    [BsonElement("status")]
+    public string? Status { get; set; }
+    [BsonElement("user_id")]
+    public string? UserId { get; set; }
+    [BsonElement("date_created")]
+    public DateTime? DateCreated { get; set; }
+    [BsonElement("processed")]
+    public bool? Processed { get; set; }
+    #endregion
+}
\ No newline at end of file
diff --git a/Models/Text.cs b/Models/Text.cs
new file mode 100644
index 0000000..8a5e8b0
--- /dev/null
+++ b/Models/Text.cs
@@ -0,0 +1,14 @@
+using System;
+
+namespace TextSender_API.Models;
+
+public class Text
+{
+#region Properties
+    public int TextID { get; set; }
+    public string? Subject { get; set; }
+    public string? Message { get; set; }
+    public int UserID { get; set; }
+    public DateTime DateCreated { get; set; }
+#endregion
+}
diff --git a/Models/TextQueue.cs b/Models/TextQueue.cs
new file mode 100644
index 0000000..9d7327b
--- /dev/null
+++ b/Models/TextQueue.cs
@@ -0,0 +1,16 @@
+using System;
+
+namespace TextSender_API.Models;
+
+public class TextQueue
+{
+#region Properties
+    public int TextQueueID { get; set; }
+    public string? Status { get; set; }
+    public string? ContactPhoneNumber { get; set; }
+    public int TextID { get; set; }
+    public int UserID { get; set; }
+    public DateTime DateCreated { get; set; }
+    public DateTime ExecutionDate { get; set; }
+#endregion
+}
diff --git a/Models/Token.cs b/Models/Token.cs
new file mode 100644
index 0000000..afbe858
--- /dev/null
+++ b/Models/Token.cs
@@ -0,0 +1,17 @@
+using Newtonsoft.Json;
+
+namespace TextSender_API.Models;
+
+public class Token
+{
+    #region Properties
+    [JsonProperty("access_token")]
+    public string? AccessToken { get; set; }
+    [JsonProperty("token_type")]
+    public string? TokenType { get; set; }
+    [JsonProperty("issued")]
+    public DateTime? Issued { get; set; }
+    [JsonProperty("id")]
+    public string? UserId { get; set; }
+    #endregion
+}
\ No newline at end of file
diff --git a/Models/User.cs b/Models/User.cs
new file mode 100644
index 0000000..9cbf051
--- /dev/null
+++ b/Models/User.cs
@@ -0,0 +1,46 @@
+using MongoDB.Bson;
+using MongoDB.Bson.Serialization.Attributes;
+using Newtonsoft.Json;
+
+namespace TextSender_API.Models;
+
+public class User
+{
+#region Properties
+    [BsonId]
+    [BsonRepresentation(BsonType.ObjectId)]
+    [JsonProperty("id")]
+    public string? Id { get; set; }
+    [BsonElement("firstname")]
+    [JsonProperty("firstname")]
+    public string? Firstname { get; set; }
+    [BsonElement("lastname")]
+    [JsonProperty("lastname")]
+    public string? Lastname { get; set; }
+    [BsonElement("phonenumber")]
+    [JsonProperty("phone_number")]
+    public string? PhoneNumber { get; set; }
+    [BsonElement("username")]
+    [JsonProperty("username")]
+    public string? Username { get; set; }
+    [BsonElement("password")]
+    [JsonProperty("password")]
+    public string? Password { get; set; }
+    [BsonElement("datecreated")]
+    [JsonProperty("date_created")]
+    public DateTime? DateCreated { get; set; }
+#endregion
+}
+
+public class Salt
+{
+    #region Properties
+    [BsonId]
+    [BsonRepresentation(BsonType.ObjectId)]
+    public string? Id { get; set; }
+    [BsonElement("key")]
+    public byte[]? Key { get; set; }
+    [BsonElement("user_id")]
+    public string?  UserId { get; set; }
+    #endregion
+}
diff --git a/Program.cs b/Program.cs
new file mode 100644
index 0000000..66aca82
--- /dev/null
+++ b/Program.cs
@@ -0,0 +1,63 @@
+using System.Text;
+
+using Microsoft.AspNetCore.Authentication.JwtBearer;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.Extensions.Configuration;
+using Microsoft.IdentityModel.Tokens;
+
+using TextSender_API.Repositories;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Add services to the container.
+
+builder.Services.AddControllers();
+builder.Services.AddControllers().AddNewtonsoftJson();
+
+// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen();
+
+builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme).AddJwtBearer(options =>
+{
+    options.RequireHttpsMetadata = false;
+    options.SaveToken = true;
+    options.TokenValidationParameters = new TokenValidationParameters()
+    {
+        ValidateIssuer = true,
+        ValidateAudience = true,
+        ValidAudience = builder.Configuration["JWT:Audience"],
+        ValidIssuer = builder.Configuration["JWT:Issuer"],
+        RequireExpirationTime = false,
+        ValidateIssuerSigningKey = false,
+        IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(builder.Configuration["JWT:Secret"]!))
+    };
+});
+
+// var connectionString = builder.Configuration.GetConnectionString("MongoDBURI");
+
+
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+
+app.UseHttpsRedirection();
+
+app.UseAuthentication();
+app.UseRouting();
+app.UseAuthorization();
+app.UseEndpoints(endpoints =>
+{
+    endpoints.MapControllers();
+});
+
+// app.MapControllers();
+
+app.Run();
diff --git a/Properties/launchSettings.json b/Properties/launchSettings.json
new file mode 100644
index 0000000..e609dd5
--- /dev/null
+++ b/Properties/launchSettings.json
@@ -0,0 +1,41 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:22514",
+      "sslPort": 44361
+    }
+  },
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "http://localhost:5168",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "https://localhost:7154;http://localhost:5168",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}
diff --git a/README.md b/README.md
index 33e7395..b8543de 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,11 @@ An API used to send texts messages to multiple contacts.
 ## Getting started
 
 Installing dependencies
-`npm install`
+```BASH
+dotnet restore
+```
 
 Running server
-`node app.js`
+```BASH
+dotnet run
+```
diff --git a/Repositories/BaseRepository.cs b/Repositories/BaseRepository.cs
new file mode 100644
index 0000000..e437670
--- /dev/null
+++ b/Repositories/BaseRepository.cs
@@ -0,0 +1,11 @@
+
+namespace TextSender_API.Repositories;
+
+public class BaseRepository
+{
+    #region Fields
+    protected string? _connectionString;
+    protected string _databaseName = "textSender";
+    protected string? _tableName;
+    #endregion
+}
\ No newline at end of file
diff --git a/Repositories/ContactRepository.cs b/Repositories/ContactRepository.cs
new file mode 100644
index 0000000..b4d9ceb
--- /dev/null
+++ b/Repositories/ContactRepository.cs
@@ -0,0 +1,131 @@
+using MongoDB.Driver;
+
+using TextSender_API.Models;
+
+namespace TextSender_API.Repositories;
+
+
+public class ContactCreationQueueRepository : BaseRepository
+{
+    #region Fields
+    private readonly IMongoCollection<ContactCreationQueue> _bookCollection;
+    #endregion
+
+
+    #region Constructors
+    public ContactCreationQueueRepository(string connectionString)
+    {
+        this._connectionString = connectionString;
+        this._tableName = "contactCreationQueue";
+        var client = this.InitializeClient();
+        this._bookCollection = client.GetDatabase(this._databaseName).GetCollection<ContactCreationQueue>(this._tableName);
+    }
+    #endregion
+
+    #region Metods
+    public Tuple<bool, ContactCreationQueue> Exists(string id)
+    {
+        var allQueue = this.RetrieveAll();
+        var result = allQueue.FirstOrDefault(q => q.Id!.Equals(id));
+
+        if (result != null)
+        {
+            return new Tuple<bool, ContactCreationQueue>(true, result!);
+        }
+        else
+        {
+            return new Tuple<bool, ContactCreationQueue>(false, new ContactCreationQueue());
+        }
+    }
+
+    public void Create(ContactCreationQueue queue)
+    {
+        this._bookCollection.InsertOne(queue);
+    }
+
+    public List<ContactCreationQueue> RetrieveAll()
+    {
+        return this._bookCollection.Find(_ => true).ToList();
+    }
+
+    public void Update(ContactCreationQueue queue)
+    {
+        var filter = Builders<ContactCreationQueue>.Filter.Eq(q => q.Id, queue.Id);
+        this._bookCollection.ReplaceOne(filter, queue);
+    }
+
+    public void Delete(ContactCreationQueue queue)
+    {
+        var filter = Builders<ContactCreationQueue>.Filter.Eq(q => q.Id, queue.Id);
+        this._bookCollection.DeleteOne(filter);
+    }
+
+    private MongoClient InitializeClient()
+    {
+        return new MongoClient(this._connectionString);
+    }
+    #endregion
+}
+
+
+public class ContactsRepository : BaseRepository
+{
+    #region Fields
+    private readonly IMongoCollection<Contact> _bookCollection;
+    #endregion
+
+
+    #region Constructors
+    public ContactsRepository(string connectionString)
+    {
+        this._connectionString = connectionString;
+        this._tableName = "contacts";
+        var client = this.InitializeClient();
+        this._bookCollection = client.GetDatabase(this._databaseName).GetCollection<Contact>(this._tableName);
+    }
+    #endregion
+
+    #region Metods
+    public Tuple<bool, Contact> Exists(string id)
+    {
+        var allContacts= this.RetrieveAll();
+        var result = allContacts.FirstOrDefault(c => c.Id!.Equals(id));
+
+        if (result != null)
+        {
+            return new Tuple<bool, Contact>(true, result!);
+        }
+        else
+        {
+            return new Tuple<bool, Contact>(false, new Contact());
+        }
+    }
+
+    public void Create(Contact contact)
+    {
+        this._bookCollection.InsertOne(contact);
+    }
+
+    public List<Contact> RetrieveAll()
+    {
+        return this._bookCollection.Find(_ => true).ToList();
+    }
+
+    public void Update(Contact contact)
+    {
+        var filter = Builders<Contact>.Filter.Eq(c => c.Id, contact.Id);
+        this._bookCollection.ReplaceOne(filter, contact);
+    }
+
+    public void Delete(Contact contact)
+    {
+        var filter = Builders<Contact>.Filter.Eq(c => c.Id, contact.Id);
+        this._bookCollection.DeleteOne(filter);
+    }
+
+    private MongoClient InitializeClient()
+    {
+        return new MongoClient(this._connectionString);
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/Repositories/UsersRepository.cs b/Repositories/UsersRepository.cs
new file mode 100644
index 0000000..c9a86a1
--- /dev/null
+++ b/Repositories/UsersRepository.cs
@@ -0,0 +1,136 @@
+using MongoDB.Driver;
+
+using TextSender_API.Models;
+
+namespace TextSender_API.Repositories;
+
+
+public class UsersRepository : BaseRepository
+{
+    #region Fields
+    private readonly IMongoCollection<User> _bookCollection;
+    #endregion
+
+
+    #region Constructors
+    public UsersRepository(string connectionString)
+    {
+        this._connectionString = connectionString;
+        this._tableName = "users";
+        var client = this.InitializeClient();
+        this._bookCollection = client.GetDatabase(this._databaseName).GetCollection<User>(this._tableName);
+    }
+    #endregion
+
+    #region Metods
+    public Tuple<bool, User> Exists(User user)
+    {
+        var allUsers = this.RetrieveAllUsers();
+        var result = allUsers.FirstOrDefault(ea => ea.Username!.Equals(user.Username));
+
+        if (result != null)
+        {
+            return new Tuple<bool, User>(true, result!);
+        }
+        else
+        {
+            return new Tuple<bool, User>(false, new User());
+        }
+    }
+    
+    public Tuple<bool, User> Exists(string userId)
+    {
+        var allUsers = this.RetrieveAllUsers();
+        var result = allUsers.FirstOrDefault(ea => ea.Id!.Equals(userId));
+
+        if (result != null)
+        {
+            return new Tuple<bool, User>(true, result!);
+        }
+        else
+        {
+            return new Tuple<bool, User>(false, new User());
+        }
+    }
+
+    public void CreateUser(User user)
+    {
+        this._bookCollection.InsertOne(user);
+    }
+
+    public List<User> RetrieveAllUsers()
+    {
+        return this._bookCollection.Find(_ => true).ToList();
+    }
+
+    public void Update(User user)
+    {
+        var filter = Builders<User>.Filter.Eq(u => u.Id, user.Id);
+        this._bookCollection.ReplaceOne(filter, user);
+    }
+
+    public void Delete(User user)
+    {
+        var filter = Builders<User>.Filter.Eq(u => u.Id, user.Id);
+        this._bookCollection.DeleteOne(filter);
+    }
+
+    private MongoClient InitializeClient()
+    {
+        return new MongoClient(this._connectionString);
+    }
+    #endregion
+}
+
+
+public class SaltRepository : BaseRepository
+{
+    #region Fields
+    private readonly IMongoCollection<Salt> _bookCollection;
+    #endregion
+
+
+    #region Constructors
+    public SaltRepository(string connectionString)
+    {
+        this._connectionString = connectionString;
+        this._tableName = "salt";
+        var client = this.InitializeClient();
+        this._bookCollection = client.GetDatabase(this._databaseName).GetCollection<Salt>(this._tableName);
+    }
+    #endregion
+
+    #region Metods
+    public void Create(Salt salt)
+    {
+        this._bookCollection.InsertOne(salt);
+    }
+
+    public List<Salt> RetrieveAll()
+    {
+        return this._bookCollection.Find(_ => true).ToList();
+    }
+
+    public Salt Retrieve(string userId)
+    {
+        return this._bookCollection.Find(s => s.UserId!.Equals(userId)).FirstOrDefault();
+    }
+
+    public void Update(Salt salt)
+    {
+        var filter = Builders<Salt>.Filter.Eq(u => u.Id, salt.Id);
+        this._bookCollection.ReplaceOne(filter, salt);
+    }
+
+    public void Delete(Salt salt)
+    {
+        var filter = Builders<Salt>.Filter.Eq(u => u.Id, salt.Id);
+        this._bookCollection.DeleteOne(filter);
+    }
+
+    private MongoClient InitializeClient()
+    {
+        return new MongoClient(this._connectionString);
+    }
+    #endregion
+}
\ No newline at end of file
diff --git a/TextSender-API.csproj b/TextSender-API.csproj
new file mode 100644
index 0000000..d4d3f0b
--- /dev/null
+++ b/TextSender-API.csproj
@@ -0,0 +1,20 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net7.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <RootNamespace>TextSender_API</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="7.0.11" />
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="7.0.11" />
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="7.0.11" />
+    <PackageReference Include="MongoDB.Driver" Version="2.21.0" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
+    <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="7.0.2" />
+  </ItemGroup>
+
+</Project>
diff --git a/app.js b/app.js
deleted file mode 100644
index c9441eb..0000000
--- a/app.js
+++ /dev/null
@@ -1,74 +0,0 @@
-require('./models.js')
-
-const express = require('express')
-const app = express()
-const port = 3000
-
-app.use(express.json())
-
-// User Routes
-app.post('/api/v1/user/new', (req, res) => {
-    res.send('Posting')
-    console.log(req.body)
-
-    // const usr = new User()
-
-    let username = req.body['username']
-
-    // usr.username = username
-
-    console.log(`Username: ${username}`)
-})
-
-// User routes
-// TODO: Not implemented
-app.post('/api/v1/login', (req, res) => {
-    res.send('Implement');
-})
-
-// Text Routes
-// Add a new text
-// TODO: Not implemented
-app.post('/api/v1/text/new', (req, res) => {
-    res.send('Create new text')
-})
-
-// Retrieve texts
-// TODO: Not implemented
-app.get('/api/v1/text', (req, res) => {
-    res.send('Create new text')
-})
-
-// Queue a text for sending
-// TODO: Not implemented
-app.post('/api/v1/text/queue', (req, res) => {
-    res.send('Queue text')
-})
-
-// Create contact
-// TODO: Not implemented
-app.post('/api/v1/contacts/new', (req, res) => {
-    res.send('Creating contact')
-})
-
-// Retrieving contacts
-// TODO: Not implemented
-app.get('/api/v1/contacts', (req, res) => {
-    res.send('Retrieving contact')
-})
-
-// Editing a contact
-// TODO: Not implemented
-app.patch('/api/v1/contacts', (req, res) => {
-    res.send('Editing contact')
-})
-
-// Deleting a contact
-// TODO: Not implemented
-app.delete('/api/v1/contacts', (req, res) => {
-    res.send('Delete contact')
-})
-
-app.listen(port, () => {
-    console.log(`textsender-api listening on port ${port}`)
-})
diff --git a/appsettings.Development.json b/appsettings.Development.json
new file mode 100644
index 0000000..e0a901f
--- /dev/null
+++ b/appsettings.Development.json
@@ -0,0 +1,20 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "JWT": {
+    "Audience": "",
+    "Issuer": "",
+    "Secret": "",
+    "Subject": ""
+  },
+  "Paths": {
+    "ContactQueueDirectory": "/home/user/path/"
+  },
+  "ConnectionStrings": {
+    "MongoDBURI": "mongodb+srv://<username>:<password>@cluster0.abc.mongodb.net/?retryWrites=true&w=majority"
+  }
+}
diff --git a/appsettings.json b/appsettings.json
new file mode 100644
index 0000000..8a3238e
--- /dev/null
+++ b/appsettings.json
@@ -0,0 +1,21 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*",
+  "JWT": {
+    "Audience": "",
+    "Issuer": "",
+    "Secret": "",
+    "Subject": ""
+  },
+  "Paths": {
+    "ContactQueueDirectory": "/home/user/path/"
+  },
+  "ConnectionStrings": {
+    "MongoDBURI": "mongodb+srv://<username>:<password>@cluster0.abc.mongodb.net/?retryWrites=true&w=majority"
+  }
+}
diff --git a/models.js b/models.js
deleted file mode 100644
index 53d57f2..0000000
--- a/models.js
+++ /dev/null
@@ -1,14 +0,0 @@
-const mongoose = require('mongoose');
-
-const Schema = mongoose.Schema;
-const ObjectId = Schema.ObjectId;
-
-const User = new Schema({
-    userID: { type: String },
-    firstName: { type: String },
-    lastName: { type: String },
-    phoneNumber: { type: String },
-    username: { type: String },
-    password: { type: String },
-    dateCreated: { type: Date, default: Date.now }
-});
diff --git a/package.json b/package.json
deleted file mode 100644
index 39db95f..0000000
--- a/package.json
+++ /dev/null
@@ -1,16 +0,0 @@
-{
-  "name": "textsender-api",
-  "version": "0.1.0",
-  "description": "Web API for queueing text message notifications",
-  "main": "index.js",
-  "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
-  },
-  "author": "kdeng00",
-  "license": "ISC",
-  "dependencies": {
-    "express": "^4.18.2",
-    "mongodb": "^5.3.0",
-    "mongoose": "^7.0.5"
-  }
-}
diff --git a/textsender-api.sln b/textsender-api.sln
new file mode 100644
index 0000000..b57d8ea
--- /dev/null
+++ b/textsender-api.sln
@@ -0,0 +1,25 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.5.002.0
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "TextSender-API", "TextSender-API.csproj", "{AD184BBA-C715-4112-95A9-530F05323BEE}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{AD184BBA-C715-4112-95A9-530F05323BEE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{AD184BBA-C715-4112-95A9-530F05323BEE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{AD184BBA-C715-4112-95A9-530F05323BEE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{AD184BBA-C715-4112-95A9-530F05323BEE}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {70126048-DECC-43EE-9956-2CEF937B7AA1}
+	EndGlobalSection
+EndGlobal