diff --git a/.cargo/config b/.cargo/config
index 38828f1cb6e..b6df9194d4b 100644
--- a/.cargo/config
+++ b/.cargo/config
@@ -6,12 +6,6 @@ test-all = "test --manifest-path rustfmt-core/Cargo.toml"
 test-bin = "test --manifest-path rustfmt-core/rustfmt-bin/Cargo.toml"
 tb = "test-bin"
 
-test-config = "test --manifest-path rustfmt-core/rustfmt-config/Cargo.toml"
-tc = "test-config"
-
-test-emitter = "test --manifest-path rustfmt-core/rustfmt-emitter/Cargo.toml"
-te = "test-emitter"
-
 test-lib = "test --manifest-path rustfmt-core/rustfmt-lib/Cargo.toml"
 tl = "test-lib"
 
diff --git a/.github/workflows/integration.yml b/.github/workflows/integration.yml
index ba994110d24..7edaee34b45 100644
--- a/.github/workflows/integration.yml
+++ b/.github/workflows/integration.yml
@@ -6,6 +6,11 @@ jobs:
     runs-on: ubuntu-latest
     name: ${{ matrix.integration }}
     strategy:
+      # https://help.github.com/en/actions/getting-started-with-github-actions/about-github-actions#usage-limits
+      # There's a limit of 60 concurrent jobs across all repos in the rust-lang organization.
+      # In order to prevent overusing too much of that 60 limit, we throttle the
+      # number of rustfmt jobs that will run concurrently.
+      max-parallel: 4
       fail-fast: false
       matrix:
         integration: [
diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 8a27dac4fc6..33894dd0c87 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -6,6 +6,11 @@ jobs:
     runs-on: ubuntu-latest
     name: (${{ matrix.target }}, ${{ matrix.channel }}, ${{ matrix.cfg-release-channel }})
     strategy:
+      # https://help.github.com/en/actions/getting-started-with-github-actions/about-github-actions#usage-limits
+      # There's a limit of 60 concurrent jobs across all repos in the rust-lang organization.
+      # In order to prevent overusing too much of that 60 limit, we throttle the
+      # number of rustfmt jobs that will run concurrently.
+      max-parallel: 1
       fail-fast: false
       matrix:
         target: [
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 463377d3a12..3385f4463be 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -6,6 +6,11 @@ jobs:
     runs-on: windows-latest
     name: (${{ matrix.target }}, ${{ matrix.channel }})
     strategy:
+      # https://help.github.com/en/actions/getting-started-with-github-actions/about-github-actions#usage-limits
+      # There's a limit of 60 concurrent jobs across all repos in the rust-lang organization.
+      # In order to prevent overusing too much of that 60 limit, we throttle the
+      # number of rustfmt jobs that will run concurrently.
+      max-parallel: 1
       fail-fast: false
       matrix:
         target: [