Often we find ourselves with a large amount of tension in some connections involving the roof loads and it is necessary to add some steel instead of relying on wooden pegs to do the job. This is not just a new age practice but one that has been around for a long time. An easy way to solve this is to utilize mortise and tenon with an all thread rod, with a piece of all thread and some nuts and bolts that you can find at your local hardware store.
This particular joint is a housed beam into a post with a small stub tenon to serve as a locator and a piece of all thread with a 3 inch x 3 inch x 1/4 inch washer and a standard nut on both ends. Depending on the amount of tension involved you can up size or down size the diameter of the all thread to match the loads. Once again I always defer to an engineer to determine this and the size of the washer.