DeveloperController.cs

[Produces("application/json")]
[Route("api/[controller]")]
public class DeveloperController : ControllerBase
{
    private readonly DatabaseContext _context;

    public DeveloperController(DatabaseContext context)
    {
        _context = context;
    }

    [HttpPost]
    public async Task<IActionResult> CreateUser([FromBody] Developer developer)
    {
        _context.Developer.Add(developer);
        await _context.SaveChangesAsync();
        return CreatedAtAction("Get", new { id = developer.Id }, developer);
    }

    [HttpGet]
    [Route("{id}")]
    public async Task<ActionResult<Developer>> Get(int id)
    {
        var developer = await _context.Developer.FindAsync(id);
        if (developer == null) return NotFound();
        return developer;
    }

    [HttpGet]
    public IEnumerable<Developer> Get() => _context.Developer.AsQueryable();
}