diff --git a/src/factory/Workflow.cc b/src/factory/Workflow.cc
index 7431317d..63ffbb53 100644
--- a/src/factory/Workflow.cc
+++ b/src/factory/Workflow.cc
@@ -25,9 +25,9 @@
 #include "Workflow.h"
 
 SeriesWork::SeriesWork(SubTask *first, series_callback_t&& cb) :
-	queue(new SubTask *[4]),
 	callback(std::move(cb))
 {
+	this->queue = new SubTask *[4];
 	this->queue_size = 4;
 	this->front = 0;
 	this->back = 0;
diff --git a/src/factory/Workflow.h b/src/factory/Workflow.h
index f7cdb7cf..b16b9aaa 100644
--- a/src/factory/Workflow.h
+++ b/src/factory/Workflow.h
@@ -114,6 +114,10 @@ public:
 		this->last = last;
 	}
 
+protected:
+	void *context;
+	series_callback_t callback;
+
 private:
 	SubTask *pop_task();
 	void expand_queue();
@@ -128,13 +132,11 @@ private:
 	int back;
 	bool in_parallel;
 	bool canceled;
-	void *context;
 	std::mutex mutex;
-	series_callback_t callback;
 
-private:
+protected:
 	SeriesWork(SubTask *first, series_callback_t&& callback);
-	~SeriesWork() { delete []this->queue; }
+	virtual ~SeriesWork() { delete []this->queue; }
 	friend class ParallelWork;
 	friend class Workflow;
 };
@@ -230,9 +232,13 @@ public:
 		this->callback = std::move(callback);
 	}
 
-private:
+protected:
 	virtual SubTask *done();
 
+protected:
+	void *context;
+	parallel_callback_t callback;
+
 private:
 	void expand_buf();
 	void dismiss_recursive();
@@ -240,10 +246,8 @@ private:
 private:
 	size_t buf_size;
 	SeriesWork **all_series;
-	void *context;
-	parallel_callback_t callback;
 
-private:
+protected:
 	ParallelWork(parallel_callback_t&& callback);
 	ParallelWork(SeriesWork *const all_series[], size_t n,
 				 parallel_callback_t&& callback);