--- a/js/src/devtools/rootAnalysis/mozconfig.haz
+++ b/js/src/devtools/rootAnalysis/mozconfig.haz
@@ -17,31 +17,31 @@ MOZ_AUTOMATION_PACKAGE_TESTS=0
 MOZ_AUTOMATION_UPLOAD=0
 
 ac_add_options --enable-js-shell
 
 # The objdir must be at a known location so its path can be stripped from the
 # filenames stored by the analysis
 mk_add_options MOZ_OBJDIR=obj-analyzed
 
-export LLVM_CONFIG=$TOOLTOOL_DIR/clang/bin/llvm-config
-export CBINDGEN="${TOOLTOOL_DIR}/cbindgen/cbindgen"
+export LLVM_CONFIG=$MOZ_FETCHES_DIR/clang/bin/llvm-config
+export CBINDGEN="${MOZ_FETCHES_DIR}/cbindgen/cbindgen"
 
 # The configuration options are chosen to compile the most code
 # (--enable-debug, --enable-tests) in the trickiest way possible
 # (--enable-optimize) to maximize the chance of seeing tricky static orderings.
 ac_add_options --enable-debug
 ac_add_options --enable-tests
 ac_add_options --enable-optimize
-ac_add_options --with-compiler-wrapper=$TOOLTOOL_DIR/sixgill/usr/libexec/sixgill/scripts/wrap_gcc/basecc
+ac_add_options --with-compiler-wrapper=$MOZ_FETCHES_DIR/sixgill/usr/libexec/sixgill/scripts/wrap_gcc/basecc
 ac_add_options --without-ccache
 
 ac_add_options --disable-replace-malloc
 
 # -Wattributes is very verbose due to attributes being ignored on template
 # instantiations. -Wignored-attributes is very verbose due to attributes being
 # ignored on template parameters.
 CFLAGS="$CFLAGS -Wno-attributes -Wno-ignored-attributes"
 CPPFLAGS="$CPPFLAGS -Wno-attributes -Wno-ignored-attributes"
 CXXFLAGS="$CXXFLAGS -Wno-attributes -Wno-ignored-attributes"
 
-NODEJS="$TOOLTOOL_DIR/node/bin/node"
-NASM="$TOOLTOOL_DIR/nasm/nasm"
+NODEJS="$MOZ_FETCHES_DIR/node/bin/node"
+NASM="$MOZ_FETCHES_DIR/nasm/nasm"

--- a/taskcluster/ci/hazard/kind.yml
+++ b/taskcluster/ci/hazard/kind.yml
@@ -5,17 +5,16 @@
 loader: taskgraph.loader.transform:loader
 
 kind-dependencies:
     - toolchain
 
 transforms:
     - taskgraph.transforms.build_attrs:transforms
     - taskgraph.transforms.build_lints:transforms
-    - taskgraph.transforms.use_toolchains:transforms
     - taskgraph.transforms.job:transforms
     - taskgraph.transforms.task:transforms
 
 job-defaults:
     attributes:
         retrigger: true
     treeherder:
         kind: build
@@ -38,38 +37,40 @@ jobs:
             using: hazard
             command: >
                 cd /builds/worker/checkouts/gecko/taskcluster/scripts/builder
                 && ./build-haz-linux.sh --project shell $HOME/workspace
         when:
             files-changed:
                 - js/public/**
                 - js/src/**
-        toolchains:
-            - linux64-clang
-            - linux64-gcc-6
-            - linux64-gcc-sixgill
-            - linux64-rust
-            - linux64-cbindgen
-            - linux64-node
+        fetches:
+            toolchain:
+                - linux64-clang
+                - linux64-gcc-6
+                - linux64-gcc-sixgill
+                - linux64-rust
+                - linux64-cbindgen
+                - linux64-node
 
     linux64-haz/debug:
         description: "Browser Hazard Analysis Linux"
         index:
             product: firefox
             job-name: browser-haz-debug
         treeherder:
             platform: linux64/debug
             symbol: H
         run:
             using: hazard
             mozconfig: "browser/config/mozconfigs/linux64/hazards"
             command: >
                 cd /builds/worker/checkouts/gecko/taskcluster/scripts/builder
                 && ./build-haz-linux.sh --project browser $HOME/workspace
-        toolchains:
-            - linux64-clang
-            - linux64-gcc-6
-            - linux64-gcc-sixgill
-            - linux64-rust
-            - linux64-cbindgen
-            - linux64-nasm
-            - linux64-node
+        fetches:
+            toolchain:
+                - linux64-clang
+                - linux64-gcc-6
+                - linux64-gcc-sixgill
+                - linux64-rust
+                - linux64-cbindgen
+                - linux64-nasm
+                - linux64-node

--- a/taskcluster/scripts/builder/build-haz-linux.sh
+++ b/taskcluster/scripts/builder/build-haz-linux.sh
@@ -3,28 +3,26 @@
 function usage() {
     echo "Usage: $0 [--project <shell|browser>] <workspace-dir> flags..."
     echo "flags are treated the same way as a commit message would be"
     echo "(as in, they are scanned for directives just like a try: ... line)"
 }
 
 PROJECT=shell
 WORKSPACE=
-DO_TOOLTOOL=1
 while [[ $# -gt 0 ]]; do
     if [[ "$1" == "-h" ]] || [[ "$1" == "--help" ]]; then
         usage
         exit 0
     elif [[ "$1" == "--project" ]]; then
         shift
         PROJECT="$1"
         shift
     elif [[ "$1" == "--no-tooltool" ]]; then
         shift
-        DO_TOOLTOOL=
     elif [[ -z "$WORKSPACE" ]]; then
         WORKSPACE=$( cd "$1" && pwd )
         shift
         break
     fi
 done
 
 SCRIPT_FLAGS=$*
@@ -32,38 +30,26 @@ SCRIPT_FLAGS=$*
 # Ensure all the scripts in this dir are on the path....
 DIRNAME=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
 PATH=$DIRNAME:$PATH
 
 # Use GECKO_BASE_REPOSITORY as a signal for whether we are running in automation.
 export AUTOMATION=${GECKO_BASE_REPOSITORY:+1}
 
 : "${GECKO_PATH:="$DIRNAME"/../../..}"
-: "${TOOLTOOL_CACHE:=$WORKSPACE/tt-cache}"
 
 if ! [ -d "$GECKO_PATH" ]; then
     echo "GECKO_PATH must be set to a directory containing a gecko source checkout" >&2
     exit 1
 fi
 
-# Directory to populate with tooltool-installed tools
-export TOOLTOOL_DIR="$WORKSPACE"
-
 # Directory to hold the (useless) object files generated by the analysis.
 export MOZ_OBJDIR="$WORKSPACE/obj-analyzed"
 mkdir -p "$MOZ_OBJDIR"
 
-if [ -n "$DO_TOOLTOOL" ]; then (
-    cd "$TOOLTOOL_DIR"
-    "$GECKO_PATH"/mach artifact toolchain -v\
-                ${TOOLTOOL_MANIFEST:+ --tooltool-url https://tooltool.mozilla-releng.net/ \
-                                      --tooltool-manifest "$GECKO_PATH/$TOOLTOOL_MANIFEST"} \
-                --cache-dir "$TOOLTOOL_CACHE"${MOZ_TOOLCHAINS:+ ${MOZ_TOOLCHAINS}}
-) fi
-
 export NO_MERCURIAL_SETUP_CHECK=1
 
 if [[ "$PROJECT" = "browser" ]]; then (
     cd "$WORKSPACE"
     set "$WORKSPACE"
     # Mozbuild config:
     export MOZBUILD_STATE_PATH=$WORKSPACE/mozbuild/
     # Create .mozbuild so mach doesn't complain about this

--- a/taskcluster/scripts/builder/hazard-analysis.sh
+++ b/taskcluster/scripts/builder/hazard-analysis.sh
@@ -3,24 +3,24 @@
 [ -n "$WORKSPACE" ]
 [ -n "$MOZ_OBJDIR" ]
 [ -n "$GECKO_PATH" ]
 
 HAZARD_SHELL_OBJDIR=$WORKSPACE/obj-haz-shell
 JSBIN="$HAZARD_SHELL_OBJDIR/dist/bin/js"
 JS_SRCDIR=$GECKO_PATH/js/src
 ANALYSIS_SRCDIR=$JS_SRCDIR/devtools/rootAnalysis
-GCCDIR="$TOOLTOOL_DIR/gcc"
+GCCDIR="$MOZ_FETCHES_DIR/gcc"
 
 export CC="$GCCDIR/bin/gcc"
 export CXX="$GCCDIR/bin/g++"
-export PATH="$GCCDIR/bin:$TOOLTOOL_DIR/clang/bin:$PATH"
+export PATH="$GCCDIR/bin:$MOZ_FETCHES_DIR/clang/bin:$PATH"
 export LD_LIBRARY_PATH="$GCCDIR/lib64"
-export RUSTC="$TOOLTOOL_DIR/rustc/bin/rustc"
-export CARGO="$TOOLTOOL_DIR/rustc/bin/cargo"
+export RUSTC="$MOZ_FETCHES_DIR/rustc/bin/rustc"
+export CARGO="$MOZ_FETCHES_DIR/rustc/bin/cargo"
 
 PYTHON=python2.7
 if ! which $PYTHON; then
     PYTHON=python
 fi
 
 function check_commit_msg () {
     ( set +e;
@@ -67,18 +67,18 @@ function configure_analysis () {
     mkdir -p "$analysis_dir" || true
     (
         cd "$analysis_dir"
         cat > defaults.py <<EOF
 js = "$JSBIN"
 analysis_scriptdir = "$ANALYSIS_SRCDIR"
 objdir = "$MOZ_OBJDIR"
 source = "$GECKO_PATH"
-sixgill = "$TOOLTOOL_DIR/sixgill/usr/libexec/sixgill"
-sixgill_bin = "$TOOLTOOL_DIR/sixgill/usr/bin"
+sixgill = "$MOZ_FETCHES_DIR/sixgill/usr/libexec/sixgill"
+sixgill_bin = "$MOZ_FETCHES_DIR/sixgill/usr/bin"
 EOF
 
         local rev
         rev=$(cd $GECKO_PATH && hg log -r . -T '{node|short}')
         cat > run-analysis.sh <<EOF
 #!/bin/sh
 if [ \$# -eq 0 ]; then
   set gcTypes
@@ -103,17 +103,17 @@ function run_analysis () {
 
     (
         cd "$analysis_dir"
         $PYTHON "$ANALYSIS_SRCDIR/analyze.py" -v --buildcommand="$GECKO_PATH/taskcluster/scripts/builder/hazard-${build_type}.sh"
     )
 }
 
 function analysis_self_test () {
-    LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$(dirname "$JSBIN")" $PYTHON "$ANALYSIS_SRCDIR/run-test.py" -v --js "$JSBIN" --sixgill "$TOOLTOOL_DIR/sixgill" --gccdir "$GCCDIR"
+    LD_LIBRARY_PATH="$LD_LIBRARY_PATH:$(dirname "$JSBIN")" $PYTHON "$ANALYSIS_SRCDIR/run-test.py" -v --js "$JSBIN" --sixgill "$MOZ_FETCHES_DIR/sixgill" --gccdir "$GCCDIR"
 }
 
 function grab_artifacts () {
     local analysis_dir
     analysis_dir="$1"
     local artifacts
     artifacts="$2"