SampleConcurrency.cs

using SpicyPixel.Threading;
using SpicyPixel.Threading.Tasks;
using System.Collections;

public class SampleConcurrency : ConcurrentBehaviour
{
    void Start()
    {
        print("Start Start");
        taskFactory.StartNew(Bootstrap())
            .ContinueWith(Mikostrap(), taskScheduler);
        print("Start End");
    }

    IEnumerator Bootstrap()
    {
        print("Start BootStrap");
        for (var i = 0; i < 100; i++)
        {
            yield return i;
            print("BootStrap");
        }
        print("BootStrap End");
    }

    IEnumerator Mikostrap()
    {
        print("Start Mikopero");
        for (var i = 0; i < 100; i++)
        {
            yield return i;
            print("Mikopero");
        }
        print("Mikopero End");
    }
}

SampleCoroutine.cs

using System.Collections;
using UnityEngine;

public class SampleCoroutine : MonoBehaviour
{
    IEnumerator Start()
    {
        print("Start Start");
        yield return StartCoroutine(Bootstrap());
        yield return StartCoroutine(Mikostrap());
        print("Start End");
    }

    IEnumerator Bootstrap()
    {
        print("Start BootStrap");
        for (var i = 0; i < 100; i++)
        {
            yield return i;
            print("BootStrap");
        }
        print("BootStrap End");
    }

    IEnumerator Mikostrap()
    {
        print("Start Mikopero");
        for (var i = 0; i < 100; i++)
        {
            yield return i;
            print("Mikopero");
        }
        print("Mikopero End");
    }
}