diff --git a/python/servo/build_commands.py b/python/servo/build_commands.py
index b9d2a90ad79..2aa70862fd6 100644
--- a/python/servo/build_commands.py
+++ b/python/servo/build_commands.py
@@ -30,7 +30,7 @@ from mach.decorators import (
 from mach.registrar import Registrar
 
 from mach_bootstrap import _get_exec_path
-from servo.command_base import CommandBase, cd, call, check_call, BIN_SUFFIX, append_to_path_env, gstreamer_root
+from servo.command_base import CommandBase, cd, call, check_call, append_to_path_env, gstreamer_root
 from servo.util import host_triple
 
 
@@ -237,14 +237,6 @@ class MachCommands(CommandBase):
         if very_verbose:
             opts += ["-vv"]
 
-        if target:
-            if self.config["tools"]["use-rustup"] and not uwp:
-                # 'rustup target add' fails if the toolchain is not installed at all.
-                self.call_rustup_run(["rustc", "--version"])
-
-                check_call(["rustup" + BIN_SUFFIX, "target", "add",
-                            "--toolchain", self.rust_toolchain(), target])
-
         env = self.build_env(target=target, is_build=True, uwp=uwp, features=features)
         self.ensure_bootstrapped(target=target)
         self.ensure_clobbered()
diff --git a/python/servo/command_base.py b/python/servo/command_base.py
index 43e993f0907..e1edecd957a 100644
--- a/python/servo/command_base.py
+++ b/python/servo/command_base.py
@@ -1016,6 +1016,15 @@ install them, let us know by filing a bug!")
         if "msvc" in target_platform:
             Registrar.dispatch("bootstrap", context=self.context)
 
+        if target:
+            if self.config["tools"]["use-rustup"] and not "uwp" in target:
+                # 'rustup target add' fails if the toolchain is not installed at all.
+                self.call_rustup_run(["rustc", "--version"])
+
+                check_call(["rustup" + BIN_SUFFIX, "target", "add",
+                            "--toolchain", self.rust_toolchain(), target])
+
+
         self.context.bootstrapped = True
 
     def ensure_clobbered(self, target_dir=None):
diff --git a/python/servo/devenv_commands.py b/python/servo/devenv_commands.py
index 45a3f946f38..658ef547f21 100644
--- a/python/servo/devenv_commands.py
+++ b/python/servo/devenv_commands.py
@@ -49,7 +49,7 @@ class MachCommands(CommandBase):
 
         features += self.pick_media_stack(media_stack, target)
 
-        self.ensure_bootstrapped()
+        self.ensure_bootstrapped(target=target)
         self.ensure_clobbered()
         env = self.build_env()
 
diff --git a/python/servo/post_build_commands.py b/python/servo/post_build_commands.py
index 18b43a1afe0..941999fdc0b 100644
--- a/python/servo/post_build_commands.py
+++ b/python/servo/post_build_commands.py
@@ -241,13 +241,13 @@ class PostBuildCommands(CommandBase):
     @CommandBase.build_like_command_arguments
     def doc(self, params, features, target=None, android=False, magicleap=False,
             media_stack=None, **kwargs):
+        self.ensure_bootstrapped()
         rustc_path = check_output(
             ["rustup" + BIN_SUFFIX, "which", "--toolchain", self.rust_toolchain(), "rustc"])
         assert path.basename(path.dirname(rustc_path)) == "bin"
         toolchain_path = path.dirname(path.dirname(rustc_path))
         rust_docs = path.join(toolchain_path, "share", "doc", "rust", "html")
 
-        self.ensure_bootstrapped()
         docs = path.join(self.get_target_dir(), "doc")
         if not path.exists(docs):
             os.makedirs(docs)