Switch everything to platforms

This patch switches the codebase over from using the "cpu"
mechanism to using bazel platforms. See
https://docs.bazel.build/versions/master/platforms.html for some more
information.

Most of the substantial changes are in //tools. Instead of using
`cc_toolchain_suite` rules, we now use regular `toolchain` rules that
are registered in the WORKSPACE. That also means that bazel now uses
the target platform to select the compiler.

All --cpu=* arguments should now be --config=* arguments. For example,
`--cpu=roborio` should now be `--config=roborio`. The CI script and
all documentation has been updated to reflect that.

The remainder of the changes revolve around tagging all targets with
`target_compatible_with`.  The old mechanism allowed us to specify
repo-wide defaults. The new mechanism does not. That means every
target that didn't have any compatibility specified, now requires
compatibility with `@platforms//os:linux`.

I used buildozer for the vast majority of `target_compatible_with`
changes. buildozer automatically buildifies any BUILD files it
touches. That means this patch also contains a few non-functional
changes that I was too lazy to remove.

Change-Id: I66d6e6ad9161520ee397597cdb492585820a3acd
diff --git a/y2020/BUILD b/y2020/BUILD
index 59642fe..e54c168 100644
--- a/y2020/BUILD
+++ b/y2020/BUILD
@@ -21,6 +21,7 @@
         "//y2020/control_loops/drivetrain:drivetrain",
         "//y2020/control_loops/superstructure:superstructure",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 robot_downloader(
@@ -34,13 +35,13 @@
     dirs = [
         "//y2020/www:www_files",
     ],
-    restricted_to = ["//tools:armhf-debian"],
     start_binaries = [
         "//aos/network:message_bridge_client",
         "//aos/network:message_bridge_server",
         "//aos/network:web_proxy_main",
         "//y2020/vision:camera_reader",
     ],
+    target_compatible_with = ["//tools/platforms/hardware:raspberry_pi"],
     target_type = "pi",
 )
 
@@ -52,6 +53,7 @@
     hdrs = [
         "constants.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//aos/logging",
@@ -75,7 +77,7 @@
     srcs = [
         "wpilib_interface.cc",
     ],
-    restricted_to = ["//tools:roborio"],
+    target_compatible_with = ["//tools/platforms/hardware:roborio"],
     deps = [
         ":constants",
         "//aos:init",
@@ -117,6 +119,7 @@
     srcs = [
         ":joystick_reader.cc",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":setpoint_fbs",
         "//aos:init",
@@ -146,6 +149,7 @@
         "//y2020/vision/sift:sift_training_fbs",
         "//y2020/vision:vision_fbs",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         ":config_laptop",
@@ -170,6 +174,7 @@
             "//y2020/vision:vision_fbs",
             "//aos/events/logging:logger_fbs",
         ],
+        target_compatible_with = ["@platforms//os:linux"],
         visibility = ["//visibility:public"],
         deps = [
             "//aos/events:config",
@@ -197,6 +202,7 @@
         "//y2020/vision:vision_fbs",
         "//aos/events/logging:logger_fbs",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//aos/events:config",
@@ -220,6 +226,7 @@
         "//y2020/control_loops/superstructure:superstructure_position_fbs",
         "//y2020/control_loops/superstructure:superstructure_status_fbs",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos/events:config",
         "//aos/robot_state:config",
@@ -232,6 +239,7 @@
 py_library(
     name = "python_init",
     srcs = ["__init__.py"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
@@ -245,6 +253,7 @@
         "//y2020/www:field_main_bundle.min.js",
         "//y2020/www:files",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
@@ -255,11 +264,13 @@
         "setpoint.fbs",
     ],
     gen_reflections = 1,
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 cc_binary(
     name = "setpoint_setter",
     srcs = ["setpoint_setter.cc"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":setpoint_fbs",
         "//aos:init",
@@ -272,6 +283,7 @@
         name = "y2020_pi" + str(num) + ".json",
         src = "y2020_pi_template.json",
         parameters = {"NUM": str(num)},
+        target_compatible_with = ["@platforms//os:linux"],
     )
     for num in range(1, 5)
 ]
diff --git a/y2020/actors/BUILD b/y2020/actors/BUILD
index b294a51..fee0196 100644
--- a/y2020/actors/BUILD
+++ b/y2020/actors/BUILD
@@ -24,6 +24,7 @@
         "auto_splines.h",
         "autonomous_actor.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos/events:event_loop",
         "//aos/logging",
@@ -46,6 +47,7 @@
     srcs = [
         "autonomous_actor_main.cc",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":autonomous_action_lib",
         "//aos:init",
diff --git a/y2020/control_loops/BUILD b/y2020/control_loops/BUILD
index c0aa1ee..75ca8eb 100644
--- a/y2020/control_loops/BUILD
+++ b/y2020/control_loops/BUILD
@@ -1,6 +1,7 @@
 py_library(
     name = "python_init",
     srcs = ["__init__.py"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = ["//y2020:python_init"],
 )
diff --git a/y2020/control_loops/drivetrain/BUILD b/y2020/control_loops/drivetrain/BUILD
index 7e2ba18..490b1e7 100644
--- a/y2020/control_loops/drivetrain/BUILD
+++ b/y2020/control_loops/drivetrain/BUILD
@@ -11,6 +11,7 @@
         "kalman_drivetrain_motor_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:drivetrain) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:drivetrain",
     ],
@@ -27,6 +28,7 @@
         "hybrid_velocity_drivetrain.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:polydrivetrain) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:polydrivetrain",
     ],
@@ -46,6 +48,7 @@
         "kalman_drivetrain_motor_plant.h",
         "polydrivetrain_dog_motor_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
@@ -57,6 +60,7 @@
     name = "localizer",
     srcs = ["localizer.cc"],
     hdrs = ["localizer.h"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos/containers:ring_buffer",
         "//aos/network:message_bridge_server_fbs",
@@ -77,6 +81,7 @@
     hdrs = [
         "drivetrain_base.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         ":polydrivetrain_plants",
@@ -90,6 +95,7 @@
     srcs = [
         "drivetrain_main.cc",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         ":drivetrain_base",
@@ -103,6 +109,7 @@
 aos_config(
     name = "simulation_config",
     src = "drivetrain_simulation_config.json",
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops/drivetrain:simulation_channels",
@@ -113,6 +120,7 @@
 aos_config(
     name = "replay_config",
     src = "drivetrain_replay_config.json",
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//y2020:config",
@@ -123,6 +131,7 @@
     name = "localizer_test",
     srcs = ["localizer_test.cc"],
     data = [":simulation_config"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":drivetrain_base",
         ":localizer",
@@ -143,6 +152,7 @@
         ":replay_config",
         "@drivetrain_replay//file:spinning_wheels_while_still.bfbs",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":drivetrain_base",
         "//aos:configuration",
@@ -161,6 +171,7 @@
     name = "drivetrain_replay",
     srcs = ["drivetrain_replay.cc"],
     data = ["//y2020:config"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":drivetrain_base",
         ":localizer",
diff --git a/y2020/control_loops/python/BUILD b/y2020/control_loops/python/BUILD
index e218571..34d49cb 100644
--- a/y2020/control_loops/python/BUILD
+++ b/y2020/control_loops/python/BUILD
@@ -6,7 +6,7 @@
         "drivetrain.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -22,7 +22,7 @@
         "polydrivetrain.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -37,7 +37,7 @@
         "drivetrain.py",
         "polydrivetrain.py",
     ],
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     visibility = ["//visibility:public"],
     deps = [
         ":python_init",
@@ -55,7 +55,7 @@
         "hood.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -71,7 +71,7 @@
         "intake.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -87,7 +87,7 @@
         "turret.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -103,7 +103,7 @@
         "control_panel.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":python_init",
         "//external:python-gflags",
@@ -118,7 +118,7 @@
     srcs = [
         "flywheel.py",
     ],
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         "//frc971/control_loops/python:controls",
         "@matplotlib_repo//:matplotlib2.7",
@@ -131,7 +131,7 @@
         "accelerator.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":flywheel",
         ":python_init",
@@ -146,7 +146,7 @@
         "finisher.py",
     ],
     legacy_create_init = False,
-    restricted_to = ["//tools:k8"],
+    target_compatible_with = ["@platforms//cpu:x86_64"],
     deps = [
         ":flywheel",
         ":python_init",
@@ -158,6 +158,7 @@
 py_library(
     name = "python_init",
     srcs = ["__init__.py"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = ["//y2020/control_loops:python_init"],
 )
diff --git a/y2020/control_loops/superstructure/BUILD b/y2020/control_loops/superstructure/BUILD
index e97fb12..d659920 100644
--- a/y2020/control_loops/superstructure/BUILD
+++ b/y2020/control_loops/superstructure/BUILD
@@ -12,6 +12,7 @@
         "//frc971/control_loops:control_loops_fbs_includes",
         "//frc971/control_loops:profiled_subsystem_fbs_includes",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 flatbuffer_cc_library(
@@ -20,6 +21,7 @@
         "superstructure_output.fbs",
     ],
     gen_reflections = 1,
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 flatbuffer_cc_library(
@@ -32,6 +34,7 @@
         "//frc971/control_loops:control_loops_fbs_includes",
         "//frc971/control_loops:profiled_subsystem_fbs_includes",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 flatbuffer_cc_library(
@@ -44,6 +47,7 @@
         "//frc971/control_loops:control_loops_fbs_includes",
         "//frc971/control_loops:profiled_subsystem_fbs_includes",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
 )
 
 cc_library(
@@ -54,6 +58,7 @@
     hdrs = [
         "superstructure.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":climber",
         ":superstructure_goal_fbs",
@@ -75,6 +80,7 @@
     srcs = [
         "superstructure_main.cc",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":superstructure_lib",
         "//aos:init",
@@ -90,6 +96,7 @@
     data = [
         "//y2020:config",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":superstructure_goal_fbs",
         ":superstructure_lib",
@@ -119,6 +126,7 @@
     hdrs = [
         "climber.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":superstructure_goal_fbs",
         ":superstructure_output_fbs",
diff --git a/y2020/control_loops/superstructure/accelerator/BUILD b/y2020/control_loops/superstructure/accelerator/BUILD
index 30fca08..c2a6717 100644
--- a/y2020/control_loops/superstructure/accelerator/BUILD
+++ b/y2020/control_loops/superstructure/accelerator/BUILD
@@ -1,7 +1,5 @@
 package(default_visibility = ["//visibility:public"])
 
-load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
-
 genrule(
     name = "genrule_accelerator",
     outs = [
@@ -11,6 +9,7 @@
         "integral_accelerator_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:accelerator) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:accelerator",
     ],
@@ -26,6 +25,7 @@
         "accelerator_plant.h",
         "integral_accelerator_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
diff --git a/y2020/control_loops/superstructure/control_panel/BUILD b/y2020/control_loops/superstructure/control_panel/BUILD
index 75619ca..9f46998 100644
--- a/y2020/control_loops/superstructure/control_panel/BUILD
+++ b/y2020/control_loops/superstructure/control_panel/BUILD
@@ -9,6 +9,7 @@
         "integral_control_panel_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:control_panel) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:control_panel",
     ],
@@ -24,6 +25,7 @@
         "control_panel_plant.h",
         "integral_control_panel_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
diff --git a/y2020/control_loops/superstructure/finisher/BUILD b/y2020/control_loops/superstructure/finisher/BUILD
index 2009886..7a628c8 100644
--- a/y2020/control_loops/superstructure/finisher/BUILD
+++ b/y2020/control_loops/superstructure/finisher/BUILD
@@ -1,7 +1,5 @@
 package(default_visibility = ["//visibility:public"])
 
-load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
-
 genrule(
     name = "genrule_finisher",
     outs = [
@@ -11,6 +9,7 @@
         "integral_finisher_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:finisher) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:finisher",
     ],
@@ -26,6 +25,7 @@
         "finisher_plant.h",
         "integral_finisher_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
diff --git a/y2020/control_loops/superstructure/hood/BUILD b/y2020/control_loops/superstructure/hood/BUILD
index 6c1a60b..d0e5953 100644
--- a/y2020/control_loops/superstructure/hood/BUILD
+++ b/y2020/control_loops/superstructure/hood/BUILD
@@ -9,6 +9,7 @@
         "integral_hood_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:hood) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:hood",
     ],
@@ -24,6 +25,7 @@
         "hood_plant.h",
         "integral_hood_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
diff --git a/y2020/control_loops/superstructure/intake/BUILD b/y2020/control_loops/superstructure/intake/BUILD
index 2133204..5bb5d7f 100644
--- a/y2020/control_loops/superstructure/intake/BUILD
+++ b/y2020/control_loops/superstructure/intake/BUILD
@@ -9,6 +9,7 @@
         "integral_intake_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:intake) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:intake",
     ],
@@ -24,6 +25,7 @@
         "intake_plant.h",
         "integral_intake_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
diff --git a/y2020/control_loops/superstructure/shooter/BUILD b/y2020/control_loops/superstructure/shooter/BUILD
index fe8a29a..0b65037 100644
--- a/y2020/control_loops/superstructure/shooter/BUILD
+++ b/y2020/control_loops/superstructure/shooter/BUILD
@@ -1,9 +1,8 @@
 package(default_visibility = ["//visibility:public"])
 
-load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
-
 cc_library(
     name = "shooter_plants",
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//frc971/control_loops:state_feedback_loop",
     ],
@@ -17,6 +16,7 @@
     hdrs = [
         "shooter.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":flywheel_controller",
         "//aos/controls:control_loop",
@@ -36,6 +36,7 @@
     hdrs = [
         "flywheel_controller.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos/controls:control_loop",
         "//frc971/control_loops:profiled_subsystem",
diff --git a/y2020/control_loops/superstructure/turret/BUILD b/y2020/control_loops/superstructure/turret/BUILD
index 010c6fd..3761868 100644
--- a/y2020/control_loops/superstructure/turret/BUILD
+++ b/y2020/control_loops/superstructure/turret/BUILD
@@ -9,6 +9,7 @@
         "integral_turret_plant.cc",
     ],
     cmd = "$(location //y2020/control_loops/python:turret) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         "//y2020/control_loops/python:turret",
     ],
@@ -24,6 +25,7 @@
         "integral_turret_plant.h",
         "turret_plant.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:hybrid_state_feedback_loop",
@@ -35,6 +37,7 @@
     name = "aiming",
     srcs = ["aiming.cc"],
     hdrs = ["aiming.h"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos:flatbuffers",
         "//frc971/control_loops:control_loops_fbs",
@@ -50,6 +53,7 @@
 cc_test(
     name = "aiming_test",
     srcs = ["aiming_test.cc"],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":aiming",
         "//aos/testing:googletest",
diff --git a/y2020/vision/BUILD b/y2020/vision/BUILD
index aaad085..a58ed8c 100644
--- a/y2020/vision/BUILD
+++ b/y2020/vision/BUILD
@@ -5,6 +5,7 @@
     name = "vision_fbs",
     srcs = ["vision.fbs"],
     gen_reflections = 1,
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
 )
 
@@ -16,6 +17,7 @@
     hdrs = [
         "v4l2_reader.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         ":vision_fbs",
@@ -34,10 +36,7 @@
     data = [
         "//y2020:config",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         ":v4l2_reader",
@@ -57,6 +56,7 @@
 flatbuffer_ts_library(
     name = "vision_ts_fbs",
     srcs = ["vision.fbs"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
 )
 
@@ -68,10 +68,7 @@
     data = [
         "//y2020:config",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         ":vision_fbs",
@@ -90,10 +87,7 @@
     data = [
         "//y2020:config",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         ":vision_fbs",
@@ -117,10 +111,7 @@
     data = [
         "//y2020:config",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         ":vision_fbs",
diff --git a/y2020/vision/sift/BUILD b/y2020/vision/sift/BUILD
index 158aa94..4a0dcfb 100644
--- a/y2020/vision/sift/BUILD
+++ b/y2020/vision/sift/BUILD
@@ -6,10 +6,7 @@
     srcs = [
         "fast_gaussian_generator.cc",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//third_party:halide",
         "//third_party:halide_gengen",
@@ -25,18 +22,15 @@
     ],
     data = [
         ":fast_gaussian_generator",
-        # TODO(Brian): Replace this with something more fine-grained from the
-        # configuration fragment or something.
-        "//tools/cpp:toolchain",
         "@amd64_debian_sysroot//:sysroot_files",
     ],
-    python_version = "PY3",
-    main = "fast_gaussian_runner.py",
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
+    toolchains = [
+        "@bazel_tools//tools/cpp:current_cc_toolchain",
     ],
+    main = "fast_gaussian_runner.py",
+    python_version = "PY3",
     srcs_version = "PY2AND3",
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "@bazel_tools//tools/python/runfiles",
     ],
@@ -121,10 +115,7 @@
     hdrs = [
         "sift971.h",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
     deps = [
         ":fast_gaussian",
@@ -141,10 +132,7 @@
     hdrs = [
         "fast_gaussian.h",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":fast_gaussian_all",
         "//third_party:halide_runtime",
@@ -158,10 +146,7 @@
     srcs = [
         "fast_gaussian_test.cc",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":fast_gaussian",
         "//aos/testing:googletest",
@@ -174,10 +159,7 @@
     srcs = [
         "testing_sift.cc",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":fast_gaussian",
         "//aos:init",
@@ -207,6 +189,7 @@
         "TrainingImage",
         "TrainingData",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
@@ -214,12 +197,14 @@
     name = "sift_fbs",
     srcs = ["sift.fbs"],
     gen_reflections = True,
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
 flatbuffer_ts_library(
     name = "sift_ts_fbs",
     srcs = ["sift.fbs"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
 )
 
@@ -228,6 +213,7 @@
     srcs = ["sift_training.fbs"],
     gen_reflections = True,
     includes = [":sift_fbs_includes"],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
@@ -236,6 +222,7 @@
     srcs = ["demo_sift_training.py"],
     python_version = "PY3",
     srcs_version = "PY2AND3",
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":sift_fbs_python",
         "@opencv_contrib_nonfree_amd64//:python_opencv",
@@ -255,6 +242,7 @@
         "$(location images/demo/FRC-Image4-cleaned.png)",
         "$(location demo_sift.h)",
     ]),
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         ":demo_sift_training",
     ],
@@ -265,5 +253,6 @@
     hdrs = [
         "demo_sift.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
diff --git a/y2020/vision/sift/fast_gaussian.bzl b/y2020/vision/sift/fast_gaussian.bzl
index 0905423..5eaa4bf 100644
--- a/y2020/vision/sift/fast_gaussian.bzl
+++ b/y2020/vision/sift/fast_gaussian.bzl
@@ -1,3 +1,6 @@
+load("//tools:platforms.bzl", "platforms")
+load("//tools/build_rules:select.bzl", "cpu_select")
+
 def fast_gaussian(sigmas, sizes):
     files = []
     for _, sigma_name, _ in sigmas:
@@ -28,17 +31,22 @@
             ":fast_gaussian_runner",
         ],
         cmd = " ".join([
-            "$(location fast_gaussian_runner)",
+            "$(location :fast_gaussian_runner)",
             "'" + params.to_json() + "'",
-            # TODO(Brian): This should be RULEDIR once we have support for that.
-            "$(@D)",
-            "$(TARGET_CPU)",
-        ]),
+            "$(RULEDIR)",
+        ]) + " " + cpu_select({
+            "amd64": "k8",
+            "roborio": "roborio",
+            "armhf": "armhf-debian",
+            "cortex-m": "cortex-m",
+        }),
         outs = headers + objects + htmls,
-        restricted_to = [
-            "//tools:k8",
-            "//tools:armhf-debian",
-        ],
+        # The tool doesn't support anything other than k8 and armhf-debian
+        # right now.
+        target_compatible_with = platforms.any_of([
+            "@platforms//cpu:x86_64",
+            "//tools/platforms/hardware:raspberry_pi",
+        ]),
     )
 
     native.cc_library(
@@ -48,8 +56,4 @@
         deps = [
             "//third_party:halide_runtime",
         ],
-        restricted_to = [
-            "//tools:k8",
-            "//tools:armhf-debian",
-        ],
     )
diff --git a/y2020/vision/tools/python_code/BUILD b/y2020/vision/tools/python_code/BUILD
index 9b4eb08..4ff3397 100644
--- a/y2020/vision/tools/python_code/BUILD
+++ b/y2020/vision/tools/python_code/BUILD
@@ -1,4 +1,5 @@
 load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library", "flatbuffer_py_library")
+load("//tools:platforms.bzl", "platforms")
 
 py_binary(
     name = "load_sift_training",
@@ -17,6 +18,7 @@
     ]),
     python_version = "PY3",
     srcs_version = "PY2AND3",
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//external:python-glog",
         "//y2020/vision/sift:sift_fbs_python",
@@ -34,6 +36,7 @@
         "$(location :load_sift_training)",
         "$(location sift_training_data.h)",
     ]),
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         ":load_sift_training",
     ],
@@ -44,6 +47,7 @@
     hdrs = [
         "sift_training_data.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
@@ -63,9 +67,10 @@
     data = glob(["calib_files/*.json"]) + glob([
         "test_images/*.png",
     ]),
-    python_version = "PY3",
     main = "load_sift_training.py",
+    python_version = "PY3",
     srcs_version = "PY2AND3",
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":load_sift_training",
         "//external:python-glog",
@@ -84,6 +89,7 @@
         "$(location :load_sift_training_test)",
         "$(location sift_training_data_test.h) test",
     ]),
+    target_compatible_with = ["@platforms//os:linux"],
     tools = [
         ":load_sift_training_test",
     ],
@@ -94,6 +100,7 @@
     hdrs = [
         "sift_training_data_test.h",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )
 
@@ -102,10 +109,7 @@
     srcs = [
         "camera_param_test.cc",
     ],
-    restricted_to = [
-        "//tools:k8",
-        "//tools:armhf-debian",
-    ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         ":sift_training_data_test",
         "//aos/testing:googletest",
diff --git a/y2020/www/BUILD b/y2020/www/BUILD
index 60fb704..bbad63b 100644
--- a/y2020/www/BUILD
+++ b/y2020/www/BUILD
@@ -8,6 +8,7 @@
         "camera_main.ts",
         "image_handler.ts",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         "//aos:configuration_ts_fbs",
@@ -26,6 +27,7 @@
         "field_handler.ts",
         "field_main.ts",
     ],
+    target_compatible_with = ["@platforms//os:linux"],
     deps = [
         "//aos:configuration_ts_fbs",
         "//aos/network:connect_ts_fbs",
@@ -40,6 +42,7 @@
     name = "camera_main_bundle",
     enable_code_splitting = False,
     entry_point = "camera_main.ts",
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         "camera_main",
@@ -50,6 +53,7 @@
     name = "field_main_bundle",
     enable_code_splitting = False,
     entry_point = "field_main.ts",
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//y2020:__subpackages__"],
     deps = [
         "field_main",
@@ -73,5 +77,6 @@
         ":files",
     ],
     dir = "www",
+    target_compatible_with = ["@platforms//os:linux"],
     visibility = ["//visibility:public"],
 )