Planning a shop build, any suggestions?

Compaction is the key, rent a compactor and take all day with it, just don't rely on what they are doing to be totally correct. When I poured my slabs, I screwed in keyways, so the slabs don't shift and become unlevel. Each slab is "keyed" into the next. As you can see in this photo the furring strip is wood screwed into the form and when removed, forms a divot the entire length of the concrete, and the fresh pour fills in the void.

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