const dotenv = b.dependency("dotenv", .{ dependency options here );
    exe.root_module.addImport("dotenv", dotenv.module("dotenv"));

const dotenv = @import("dotenv");
pub fn main() !void {
    // create an allocator
    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
    const allocator = gpa.allocator();
    defer gpa.deinit();
    // init the dotenv object - this will read the .env file at runtime
    var env = try dotenv.init(allocator, ".env");
    defer env.deinit();
    // gen "Env" vars
    var database_host = env.get("DATABASE_HOST") orelse "localhost";
    var database_name = env.get("DATABASE_NAME") orelse "zigzag-data";
    ... do stuff
    // change the value of the DATABASE_HOST
    try env.put("DATABASE_HOST", "postgres.local");
}