Had dinner at Post 390 on Saturday and for all of the lists I see about Boston's gastropubs you never see Post 390 mentioned anywhere for their beer list. You can tell that the beverage manager put a lot of time into sourcing a list of local microbrews and unique and hard to find belgians.
They have about 15 beers on tap which isn't huge by Sunset grill standards but the selection of Belgians and locals on tap is very good. I had the Rapscallion Blessing which is from Holyoke and the North Coast Old Rasputin with dinner.
For the bottled beers, there are some gems that while were way out of our price range local beer nuts would make a special trip for the $80 St Bernadus Abt 12 Mangnum. It's super hard to find
The beer menu is further down the page.