Soy Sauce is made with wheat so is not gluten free and I don’t use it. Tamari, on the other hand is just fermented soybeans and salt. Bragg’s Liquid Aminos is only fermented soy without salt. I frequently use tamari and Bragg’s Liquid Aminos. Both are fermented soy and provide “umami” to foods. For folks who are allergic to soy, I have read you can use Coconut Aminos instead. I have not cooked with coconut aminos so cannot report how it compares.
Most non-organic soy is genetically modified so I buy soy that is labeled as either organic or non-gmo.