Build ASP.NET Core 8+ backend services with EF Core, auth, background jobs, and production API patterns.
npxskills add sickn33/antigravity-awesome-skills--skill dotnet-backendLoading…
You are an expert .NET/C# backend developer with 8+ years of experience building enterprise-grade APIs and services.
Use this skill when the user asks to:
Build ASP.NET Core APIs
Entity Framework Core
Authentication & Authorization
Background Services
Performance
using Microsoft.EntityFrameworkCore;
var builder = WebApplication.CreateBuilder(args);
// Services
builder.Services.AddDbContext<AppDbContext>(options =>
options.UseNpgsql(builder.Configuration.GetConnectionString("DefaultConnection")));
builder.Services.AddAuthentication().AddJwtBearer();
builder.Services.AddAuthorization();
var app = builder.Build();
// Create user endpoint
app.MapPost("/api/users", async (CreateUserRequest request, AppDbContext db) =>
{
// Validate
if (string.IsNullOrEmpty(request.Email))
return Results.BadRequest("Email is required");
// Hash password
var hashedPassword = BCrypt.Net.BCrypt.HashPassword(request.Password);
// Create user
var user = new User
{
Email = request.Email,
PasswordHash = hashedPassword,
Name = request.Name
};
db.Users.Add(user);
await db.SaveChangesAsync();
return Results.Created($"/api/users/{user.Id}", new UserResponse(user));
})
.WithName("CreateUser")
.WithOpenApi();
app.Run();
record CreateUserRequest(string Email, string Password, string Name);
record UserResponse(int Id, string Email, string Name);
[ApiController]
[Route("api/[controller]")]
public class UsersController : ControllerBase
{
private readonly AppDbContext _db;
private readonly ILogger<UsersController> _logger;
public UsersController(AppDbContext db, ILogger<UsersController> logger)
{
_db = db;
_logger = logger;
}
[HttpGet]
public async Task<ActionResult<List<UserDto>>> GetUsers()
{
var users = await _db.Users
.AsNoTracking()
.Select(u => new UserDto(u.Id, u.Email, u.Name))
.ToListAsync();
return Ok(users);
}
[HttpPost]
public async Task<ActionResult<UserDto>> CreateUser(CreateUserDto dto)
{
var user = new User
{
Email = dto.Email,
PasswordHash = BCrypt.Net.BCrypt.HashPassword(dto.Password),
Name = dto.Name
};
_db.Users.Add(user);
await _db.SaveChangesAsync();
return CreatedAtAction(nameof(GetUser), new { id = user.Id }, new UserDto(user));
}
}
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;
public class TokenService
{
private readonly IConfiguration _config;
public TokenService(IConfiguration config) => _config = config;
public string GenerateToken(User user)
{
var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_config["Jwt:Key"]!));
var credentials = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
var claims = new[]
{
new Claim(ClaimTypes.NameIdentifier, user.Id.ToString()),
new Claim(ClaimTypes.Email, user.Email),
new Claim(ClaimTypes.Name, user.Name)
};
var token = new JwtSecurityToken(
issuer: _config["Jwt:Issuer"],
audience: _config["Jwt:Audience"],
claims: claims,
expires: DateTime.UtcNow.AddHours(1),
signingCredentials: credentials
);
return new JwtSecurityTokenHandler().WriteToken(token);
}
}
public class EmailSenderService : BackgroundService
{
private readonly ILogger<EmailSenderService> _logger;
private readonly IServiceProvider _services;
public EmailSenderService(ILogger<EmailSenderService> logger, IServiceProvider services)
{
_logger = logger;
_services = services;
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
while (!stoppingToken.IsCancellationRequested)
{
using var scope = _services.CreateScope();
var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
var pendingEmails = await db.PendingEmails
.Where(e => !e.Sent)
.Take(10)
.ToListAsync(stoppingToken);
foreach (var email in pendingEmails)
{
await SendEmailAsync(email);
email.Sent = true;
}
await db.SaveChangesAsync(stoppingToken);
await Task.Delay(TimeSpan.FromMinutes(1), stoppingToken);
}
}
private async Task SendEmailAsync(PendingEmail email)
{
// Send email logic
_logger.LogInformation("Sending email to {Email}", email.To);
}
}
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Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).