Here are some minor features I would like to see that cover up a few use cases. 1. DynamicBuffer.Fixed and/or IJobProcessBufferElement While investigating this issue https://forum.unity.com/threads/silent-editor-crash-when-using-big-amounts-of-data.571501/ I tried to use DynamicBuffers like I would have a used a NativeArray. In that thread you can see that it didn't go very well. I know that FixedArray is gone but I propose a DynamicBuffer.Fixed variant of some sort that can be read and written to from an IJobParallelFor like it was a NativeArray. That would cover the case where the buffer size is known up front and the elements can be processed in parallel. On a higher level an IJobProcessBufferElement could then be offered as a convenience. Maybe such a Job could already work with the current DynamicBuffer implementation? 2. EntityCommandBuffer.CopyFrom(EntityCommandBuffer commandBuffer) I recently tried implementing an AI System that would add or remove Components after decision making, to bring the AI Agents into the wanted state. Each AI decision system could be specified by only those Components and a few AI rules. I would really like to be able to save an EntityCommandBuffer up front, pass it to a runtime instantiated AI System and then copy it to another buffer created in a BarrierSystem, inside a Job. This way I could set up many AI systems from one generic class that would be differentiated by their EntityCommandBuffers. A CopyFrom function that takes another buffer would be very helpful in this regard as currently the buffers cannot be created and associated with a BarrierSystem in separate. I think this feature would prove useful in many other scenarios as well. Edit: To clarify 2. I just want to copy an EntityCommandBuffer's contents to another ECB inside a Job. Preferably also with Concurrent buffers.