diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e8a439d2..ddee7ff8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,104 +5,195 @@ on:
     branches:
     - master
   schedule:
-    - cron: '00 01 * * *'
+  - cron: '00 01 * * *'
 jobs:
   test:
     name: test
+    env:
+      # For some builds, we use cross to test on 32-bit and big-endian
+      # systems.
+      CARGO: cargo
+      # When CARGO is set to CROSS, this is set to `--target matrix.target`.
+      TARGET_FLAGS:
+      # When CARGO is set to CROSS, TARGET_DIR includes matrix.target.
+      TARGET_DIR: ./target
+      # Emit backtraces on panics.
+      RUST_BACKTRACE: 1
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        build:
+        # We test ripgrep on a pinned version of Rust, along with the moving
+        # targets of 'stable' and 'beta' for good measure.
+        - pinned
+        - stable
+        - beta
+        # Our release builds are generated by a nightly compiler to take
+        # advantage of the latest optimizations/compile time improvements. So
+        # we test all of them here. (We don't do mips releases, but test on
+        # mips for big-endian coverage.)
+        - nightly
+        - nightly-musl
+        - nightly-32
+        - nightly-mips
+        - nightly-arm
+        - macos
+        - win-msvc
+        - win-gnu
+        include:
+        - build: pinned
+          os: ubuntu-18.04
+          rust: 1.41.0
+        - build: stable
+          os: ubuntu-18.04
+          rust: stable
+        - build: beta
+          os: ubuntu-18.04
+          rust: beta
+        - build: nightly
+          os: ubuntu-18.04
+          rust: nightly
+        - build: nightly-musl
+          os: ubuntu-18.04
+          rust: nightly
+          target: x86_64-unknown-linux-musl
+        - build: nightly-32
+          os: ubuntu-18.04
+          rust: nightly
+          target: i686-unknown-linux-gnu
+        - build: nightly-mips
+          os: ubuntu-18.04
+          rust: nightly
+          target: mips64-unknown-linux-gnuabi64
+        - build: nightly-arm
+          os: ubuntu-18.04
+          rust: nightly
+          # For stripping release binaries:
+          # docker run --rm -v $PWD/target:/target:Z \
+          #   rustembedded/cross:arm-unknown-linux-gnueabihf \
+          #   arm-linux-gnueabihf-strip \
+          #   /target/arm-unknown-linux-gnueabihf/debug/rg
+          target: arm-unknown-linux-gnueabihf
+        - build: macos
+          os: macos-latest
+          rust: nightly
+        - build: win-msvc
+          os: windows-2019
+          rust: nightly
+        - build: win-gnu
+          os: windows-2019
+          rust: nightly-x86_64-gnu
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v1
+      with:
+        fetch-depth: 1
+
+    - name: Install packages (Ubuntu)
+      if: matrix.os == 'ubuntu-18.04'
+      run: |
+        ci/ubuntu-install-packages
+
+    - name: Install packages (macOS)
+      if: matrix.os == 'macos-latest'
+      run: |
+        ci/macos-install-packages
+
+    - name: Install Rust
+      uses: actions-rs/toolchain@v1
+      with:
+        toolchain: ${{ matrix.rust }}
+        profile: minimal
+        override: true
+
+    - name: Use Cross
+      if: matrix.target != ''
+      run: |
+        # FIXME: to work around bugs in latest cross release, install master.
+        # See: https://github.com/rust-embedded/cross/issues/357
+        cargo install --git https://github.com/rust-embedded/cross
+        echo "::set-env name=CARGO::cross"
+        echo "::set-env name=TARGET_FLAGS::--target ${{ matrix.target }}"
+        echo "::set-env name=TARGET_DIR::./target/${{ matrix.target }}"
+
+    - name: Show command used for Cargo
+      run: |
+        echo "cargo command is: ${{ env.CARGO }}"
+        echo "target flag is: ${{ env.TARGET_FLAGS }}"
+
+    - name: Build ripgrep and all crates
+      run: ${{ env.CARGO }} build --verbose --all ${{ env.TARGET_FLAGS }}
+
+    - name: Build ripgrep with PCRE2
+      run: ${{ env.CARGO }} build --verbose --all --features pcre2 ${{ env.TARGET_FLAGS }}
+
+    # This is useful for debugging problems when the expected build artifacts
+    # (like shell completions and man pages) aren't generated.
+    - name: Show build.rs stderr
+      shell: bash
+      run: |
+        set +x
+        stderr="$(find "${{ env.TARGET_DIR }}/debug" -name stderr -print0 | xargs -0 ls -t | head -n1)"
+        if [ -s "$stderr" ]; then
+          echo "===== $stderr ===== "
+          cat "$stderr"
+          echo "====="
+        fi
+        set -x
+
+    - name: Run tests with PCRE2 (sans cross)
+      if: matrix.target == ''
+      run: ${{ env.CARGO }} test --verbose --all --features pcre2 ${{ env.TARGET_FLAGS }}
+
+    - name: Run tests without PCRE2 (with cross)
+      # These tests should actually work, but they almost double the runtime.
+      # Every integration test spins up qemu to run 'rg', and when PCRE2 is
+      # enabled, every integration test is run twice: one with the default
+      # regex engine and once with PCRE2.
+      if: matrix.target != ''
+      run: ${{ env.CARGO }} test --verbose --all ${{ env.TARGET_FLAGS }}
+
+    - name: Test for existence of build artifacts (Windows)
+      if: matrix.os == 'windows-2019'
+      shell: bash
+      run: |
+        outdir="$(ci/cargo-out-dir "${{ env.TARGET_DIR }}")"
+        ls "$outdir/_rg.ps1" && file "$outdir/_rg.ps1"
+
+    - name: Test for existence of build artifacts (Unix)
+      if: matrix.os != 'windows-2019'
+      shell: bash
+      run: |
+        outdir="$(ci/cargo-out-dir "${{ env.TARGET_DIR }}")"
+        for f in rg.bash rg.fish rg.1; do
+          # We could use file -E here, but it isn't supported on macOS.
+          ls "$outdir/$f" && file "$outdir/$f"
+        done
+
+    - name: Test zsh shell completions (Unix, sans cross)
+      # We could test this when using Cross, but we'd have to execute the
+      # 'rg' binary (done in test_complete.sh) with qemu, which is a pain and
+      # doesn't really gain us much. If shell completion works in one place,
+      # it probably works everywhere.
+      if: matrix.target == '' && matrix.os != 'windows-2019'
+      shell: bash
+      run: ci/test_complete.sh
+
+  rustfmt:
+    name: rustfmt
     runs-on: ubuntu-18.04
     steps:
-    - name: no-op
-      run: echo hello
-
-#  test:
-#    name: test
-#    runs-on: ${{ matrix.os }}
-#    strategy:
-#      matrix:
-#        # The docs seem to suggest that we can have a matrix with just an
-#        # include directive, but it result in a "matrix must define at least
-#        # one vector" error in the CI system.
-#        build:
-#        # - pinned-glibc
-#        - pinned-musl
-#        - stable
-#        # - beta
-#        # We test musl with nightly because every once in a while, this will
-#        # catch an upstream regression.
-#        # - nightly-glibc
-#        # - nightly-musl
-#        # - macos
-#        # - win-msvc-32
-#        # - win-msvc-64
-#        # - win-gnu-32
-#        # - win-gnu-64
-#        include:
-#        # - build: pinned-glibc
-#          # os: ubuntu-18.04
-#          # rust: 1.34.0
-#          # target: x86_64-unknown-linux-gnu
-#        - build: pinned-musl
-#          os: ubuntu-18.04
-#          rust: 1.34.0
-#          target: x86_64-unknown-linux-musl
-#        - build: stable
-#          os: ubuntu-18.04
-#          rust: stable
-#          target: x86_64-unknown-linux-gnu
-#        # - build: beta
-#          # os: ubuntu-18.04
-#          # rust: beta
-#          # target: x86_64-unknown-linux-gnu
-#        # - build: nightly-glibc
-#          # os: ubuntu-18.04
-#          # rust: nightly
-#          # target: x86_64-unknown-linux-gnu
-#        # - build: nightly-musl
-#          # os: ubuntu-18.04
-#          # rust: nightly
-#          # target: x86_64-unknown-linux-musl
-#        # - build: macos
-#          # os: macOS-10.14
-#          # rust: stable
-#          # target: x86_64-apple-darwin
-#        # - build: win-msvc-32
-#          # os: windows-2019
-#          # rust: stable
-#          # target: i686-pc-windows-msvc
-#        # - build: win-msvc-64
-#          # os: windows-2019
-#          # rust: stable
-#          # target: x86_64-pc-windows-msvc
-#        # - build: win-gnu-32
-#          # os: windows-2019
-#          # rust: stable-i686-gnu
-#          # target: i686-pc-windows-gnu
-#        # - build: win-gnu-64
-#          # os: windows-2019
-#          # rust: stable-x86_64-gnu
-#          # target: x86_64-pc-windows-gnu
-#    steps:
-#    - name: Checkout repository
-#      uses: actions/checkout@v1
-#      with:
-#        fetch-depth: 1
-#    - name: Install Rust
-#      uses: hecrj/setup-rust-action@v1
-#      with:
-#        rust-version: ${{ matrix.rust }}
-#    - name: Install Rust Target
-#      run: rustup target add ${{ matrix.target }}
-#    - name: Install musl-gcc
-#      if: contains(matrix.target, 'musl')
-#      run: |
-#        sudo apt-get install musl-tools
-#    - name: Build everything
-#      run: cargo build --verbose --target ${{ matrix.target }} --all --features pcre2
-#    - name: Install zsh
-#      if: matrix.build == 'stable'
-#      run: sudo apt-get install zsh
-#    - name: Test zsh auto-completions
-#      if: matrix.build == 'stable'
-#      run: ./ci/test_complete.sh
-#    - name: Run tests
-#      run: cargo test --verbose --target ${{ matrix.target }} --all --features pcre2
+    - name: Checkout repository
+      uses: actions/checkout@v1
+      with:
+        fetch-depth: 1
+    - name: Install Rust
+      uses: actions-rs/toolchain@v1
+      with:
+        toolchain: stable
+        override: true
+        profile: minimal
+        components: rustfmt
+    - name: Check formatting
+      run: |
+        cargo fmt --all -- --check
diff --git a/Cross.toml b/Cross.toml
index d16d10f0..3b0e4caa 100644
--- a/Cross.toml
+++ b/Cross.toml
@@ -1,2 +1,11 @@
 [target.x86_64-unknown-linux-musl]
 image = "burntsushi/cross:x86_64-unknown-linux-musl"
+
+[target.i686-unknown-linux-gnu]
+image = "burntsushi/cross:i686-unknown-linux-gnu"
+
+[target.mips64-unknown-linux-gnuabi64]
+image = "burntsushi/cross:mips64-unknown-linux-gnuabi64"
+
+[target.arm-unknown-linux-gnueabihf]
+image = "burntsushi/cross:arm-unknown-linux-gnueabihf"
diff --git a/ci/cargo-out-dir b/ci/cargo-out-dir
new file mode 100755
index 00000000..2b08d616
--- /dev/null
+++ b/ci/cargo-out-dir
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# Finds Cargo's `OUT_DIR` directory from the most recent build.
+#
+# This requires one parameter corresponding to the target directory
+# to search for the build output.
+
+if [ $# != 1 ]; then
+  echo "Usage: $(basename "$0") <target-dir>" >&2
+  exit 2
+fi
+
+# This works by finding the most recent stamp file, which is produced by
+# every ripgrep build.
+target_dir="$1"
+find "$target_dir" -name ripgrep-stamp -print0 \
+  | xargs -0 ls -t \
+  | head -n1 \
+  | xargs dirname
diff --git a/ci/docker/README.md b/ci/docker/README.md
new file mode 100644
index 00000000..58f367ef
--- /dev/null
+++ b/ci/docker/README.md
@@ -0,0 +1,24 @@
+These are Docker images used for cross compilation in CI builds (or locally)
+via the [Cross](https://github.com/rust-embedded/cross) tool.
+
+The Cross tool actually provides its own Docker images, and all Docker images
+in this directory are derived from one of them. We provide our own in order
+to customize the environment. For example, we need to install some things like
+`asciidoc` in order to generate man pages. We also install compression tools
+like `xz` so that tests for the `-z/--search-zip` flag are run.
+
+If you make a change to a Docker image, then you can re-build it. `cd` into the
+directory containing the `Dockerfile` and run:
+
+    $ cd x86_64-unknown-linux-musl
+    $ ./build
+
+At this point, subsequent uses of `cross` will now use your built image since
+Docker prefers local images over remote images. In order to make these changes
+stick, they need to be pushed to Docker Hub:
+
+    $ docker push burntsushi/cross:x86_64-unknown-linux-musl
+
+Of course, only I (BurntSushi) can push to that location. To make `cross` use
+a different location, then edit `Cross.toml` in the root of this repo to use
+a different image name for the desired target.
diff --git a/ci/docker/arm-unknown-linux-gnueabihf/Dockerfile b/ci/docker/arm-unknown-linux-gnueabihf/Dockerfile
new file mode 100644
index 00000000..59901cb5
--- /dev/null
+++ b/ci/docker/arm-unknown-linux-gnueabihf/Dockerfile
@@ -0,0 +1,4 @@
+FROM rustembedded/cross:arm-unknown-linux-gnueabihf
+
+COPY stage/ubuntu-install-packages /
+RUN /ubuntu-install-packages
diff --git a/ci/docker/arm-unknown-linux-gnueabihf/build b/ci/docker/arm-unknown-linux-gnueabihf/build
new file mode 100755
index 00000000..107b8369
--- /dev/null
+++ b/ci/docker/arm-unknown-linux-gnueabihf/build
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+mkdir -p stage
+cp ../../ubuntu-install-packages ./stage/
+docker build -t burntsushi/cross:arm-unknown-linux-gnueabihf .
diff --git a/ci/docker/i686-unknown-linux-gnu/Dockerfile b/ci/docker/i686-unknown-linux-gnu/Dockerfile
new file mode 100644
index 00000000..9c9107ea
--- /dev/null
+++ b/ci/docker/i686-unknown-linux-gnu/Dockerfile
@@ -0,0 +1,4 @@
+FROM rustembedded/cross:i686-unknown-linux-gnu
+
+COPY stage/ubuntu-install-packages /
+RUN /ubuntu-install-packages
diff --git a/ci/docker/i686-unknown-linux-gnu/build b/ci/docker/i686-unknown-linux-gnu/build
new file mode 100755
index 00000000..5837c828
--- /dev/null
+++ b/ci/docker/i686-unknown-linux-gnu/build
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+mkdir -p stage
+cp ../../ubuntu-install-packages ./stage/
+docker build -t burntsushi/cross:i686-unknown-linux-gnu .
diff --git a/ci/docker/mips64-unknown-linux-gnuabi64/Dockerfile b/ci/docker/mips64-unknown-linux-gnuabi64/Dockerfile
new file mode 100644
index 00000000..4b14616b
--- /dev/null
+++ b/ci/docker/mips64-unknown-linux-gnuabi64/Dockerfile
@@ -0,0 +1,4 @@
+FROM rustembedded/cross:mips64-unknown-linux-gnuabi64
+
+COPY stage/ubuntu-install-packages /
+RUN /ubuntu-install-packages
diff --git a/ci/docker/mips64-unknown-linux-gnuabi64/build b/ci/docker/mips64-unknown-linux-gnuabi64/build
new file mode 100755
index 00000000..a15ca352
--- /dev/null
+++ b/ci/docker/mips64-unknown-linux-gnuabi64/build
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+mkdir -p stage
+cp ../../ubuntu-install-packages ./stage/
+docker build -t burntsushi/cross:mips64-unknown-linux-gnuabi64 .
diff --git a/ci/docker/x86_64-unknown-linux-musl/Dockerfile b/ci/docker/x86_64-unknown-linux-musl/Dockerfile
index 0405c0c4..8818b605 100644
--- a/ci/docker/x86_64-unknown-linux-musl/Dockerfile
+++ b/ci/docker/x86_64-unknown-linux-musl/Dockerfile
@@ -1,5 +1,4 @@
 FROM rustembedded/cross:x86_64-unknown-linux-musl
 
-RUN apt-get update \
- && apt-get install -y --no-install-recommends \
-      libxslt1-dev asciidoc docbook-xsl xsltproc libxml2-utils
+COPY stage/ubuntu-install-packages /
+RUN /ubuntu-install-packages
diff --git a/ci/docker/x86_64-unknown-linux-musl/build b/ci/docker/x86_64-unknown-linux-musl/build
new file mode 100755
index 00000000..7fce7c2a
--- /dev/null
+++ b/ci/docker/x86_64-unknown-linux-musl/build
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+mkdir -p stage
+cp ../../ubuntu-install-packages ./stage/
+docker build -t burntsushi/cross:x86_64-unknown-linux-musl .
diff --git a/ci/macos-install-packages b/ci/macos-install-packages
new file mode 100755
index 00000000..309562f7
--- /dev/null
+++ b/ci/macos-install-packages
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+brew install asciidoc docbook-xsl
diff --git a/ci/test_complete.sh b/ci/test_complete.sh
index 0268de89..ff11c802 100755
--- a/ci/test_complete.sh
+++ b/ci/test_complete.sh
@@ -18,7 +18,7 @@ get_comp_args() {
 
 main() {
     local diff
-    local  rg="${0:a:h}/../target/${TARGET:-}/release/rg"
+    local  rg="${0:a:h}/../${TARGET_DIR:-target}/release/rg"
     local _rg="${0:a:h}/../complete/_rg"
     local -a help_args comp_args
 
diff --git a/ci/ubuntu-install-packages b/ci/ubuntu-install-packages
new file mode 100755
index 00000000..edaac6f4
--- /dev/null
+++ b/ci/ubuntu-install-packages
@@ -0,0 +1,6 @@
+#!/bin/sh
+
+sudo apt-get update
+sudo apt-get install -y --no-install-recommends \
+  libxslt1-dev asciidoc docbook-xsl xsltproc libxml2-utils \
+  zsh xz-utils liblz4-tool musl-tools