builder.AddRedisClient(connectionName: "Cache");

var sp = builder.Services.BuildServiceProvider();
var connectionStringProvider = sp.GetRequiredService<ConnectionStringProvider>();
var connectionString = connectionStringProvider.CacheConnectionString().GetAwaiter().GetResult();

builder.Configuration["ConnectionStrings:Cache"] = connectionString;

builder.AddRedisClient(connectionName: "Cache");

var connectionStringProvider = serviceProvider.GetRequiredService<ConnectionStringProvider>();
optionsBuilder // DbContextOptionsBuilder<TDbContext>
    .UseNpgsql(
      await connectionStringProvider.DatabaseConnectionString(),
     ....
   );

services.AddHealthChecks()
      .AddNpgSql(connectionStringFactory: sp =>
      {
        var connectionStringProvider = sp.GetRequiredService<ConnectionStringProvider>();
        return connectionStringProvider.DatabaseConnectionString().GetAwaiter().GetResult();
      })