try at a more modular recipe architecture.

NOTE: some of this syntax isn't toml i don't think, so this should be
treated more like pseudo-toml

modular-recipes/peristaltic-pump/bearing_roller.toml

@@ -0,0 +1,46 @@
+[[outputs]]
+bearing_roller = {quantity=6}
+
+# inputs list, similar to a cargo.toml file
+[[inputs]]
+bearing_hub_top = {version=0.1, type="printed"}
+bearing_hub = {version=0.1, type="printed"}
+
+# alternate representation of an element of the inputs list
+[[inputs.m4_20_shcs]]
+type = "M4x20 SHCS"
+quantity = 3
+comment = """These will hold the bearing rollers.  Possibly Button Heads
+Cap Screws would be better?  Probably either will work fine."""
+
+[[inputs.m4_washer]]
+type = "M4 washer"
+quantity = 6
+dimensions = "12 mm OD, 4.4 mm ID, 1 mm thick"
+comment = """The upstream repo calls for 12 mm OD but i think that's
+too big, it hits the outer race of the bearings.  Use 8mm OD instead."""
+
+[[inputs.624_bearing]]
+type = "624 bearing"
+quantity = 6
+comments = "13mm OD, 4mm ID, 5mm wide"
+
+[[inputs.m4_nuts]]
+type = "M4 nuts"
+quantity = 3
+
+[[dependencies]]
+tools = [
+    "3 mm hex driver",
+    "7 mm nut driver",
+]
+operator = {skill="assembly"}
+
+
+[[action]]
+process = """Assemble the bearing roller.  Each of the three roller
+stacks will consist of: washer, bearing, bearing, washer.  All three
+roller stacks are clamped between the bearing hub top and bottom, and
+fixed by a screw and nut."""
+
+