diff --git a/.github/workflows/aes.yml b/.github/workflows/aes.yml
index 0b4b3537..6ff77005 100644
--- a/.github/workflows/aes.yml
+++ b/.github/workflows/aes.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   # Builds for no_std platforms
   build:
diff --git a/.github/workflows/aria.yml b/.github/workflows/aria.yml
index 70c50d2f..f108318a 100644
--- a/.github/workflows/aria.yml
+++ b/.github/workflows/aria.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/belt-block.yml b/.github/workflows/belt-block.yml
index 1c387538..6b24be19 100644
--- a/.github/workflows/belt-block.yml
+++ b/.github/workflows/belt-block.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/blowfish.yml b/.github/workflows/blowfish.yml
index 8163cd1c..f5dcf81e 100644
--- a/.github/workflows/blowfish.yml
+++ b/.github/workflows/blowfish.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/camellia.yml b/.github/workflows/camellia.yml
index f11920a2..cadb3402 100644
--- a/.github/workflows/camellia.yml
+++ b/.github/workflows/camellia.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/cast5.yml b/.github/workflows/cast5.yml
index 7e576fc3..3923f018 100644
--- a/.github/workflows/cast5.yml
+++ b/.github/workflows/cast5.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/cast6.yml b/.github/workflows/cast6.yml
index 95985d8d..5519f96a 100644
--- a/.github/workflows/cast6.yml
+++ b/.github/workflows/cast6.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/des.yml b/.github/workflows/des.yml
index 65f8bf58..cb289dfe 100644
--- a/.github/workflows/des.yml
+++ b/.github/workflows/des.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/gift.yml b/.github/workflows/gift.yml
index 416b91a6..d674e60f 100644
--- a/.github/workflows/gift.yml
+++ b/.github/workflows/gift.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/idea.yml b/.github/workflows/idea.yml
index 9c4c5db9..74306fa5 100644
--- a/.github/workflows/idea.yml
+++ b/.github/workflows/idea.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/kuznyechik.yml b/.github/workflows/kuznyechik.yml
index 4d4c24ab..8fe52aa3 100644
--- a/.github/workflows/kuznyechik.yml
+++ b/.github/workflows/kuznyechik.yml
@@ -18,6 +18,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/magma.yml b/.github/workflows/magma.yml
index dfc560bb..97248b93 100644
--- a/.github/workflows/magma.yml
+++ b/.github/workflows/magma.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/rc2.yml b/.github/workflows/rc2.yml
index c6e596bc..4a429437 100644
--- a/.github/workflows/rc2.yml
+++ b/.github/workflows/rc2.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/rc5.yml b/.github/workflows/rc5.yml
index a6e010f8..c52dca02 100644
--- a/.github/workflows/rc5.yml
+++ b/.github/workflows/rc5.yml
@@ -16,6 +16,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/serpent.yml b/.github/workflows/serpent.yml
index 1a2e666d..6f5e0a2b 100644
--- a/.github/workflows/serpent.yml
+++ b/.github/workflows/serpent.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/sm4.yml b/.github/workflows/sm4.yml
index b37c858c..ffd5599b 100644
--- a/.github/workflows/sm4.yml
+++ b/.github/workflows/sm4.yml
@@ -16,6 +16,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/speck.yml b/.github/workflows/speck.yml
index 1765c489..b8ce38cf 100644
--- a/.github/workflows/speck.yml
+++ b/.github/workflows/speck.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/threefish.yml b/.github/workflows/threefish.yml
index 3a6287ed..b7b536fe 100644
--- a/.github/workflows/threefish.yml
+++ b/.github/workflows/threefish.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/twofish.yml b/.github/workflows/twofish.yml
index b7dbe188..e75dc67c 100644
--- a/.github/workflows/twofish.yml
+++ b/.github/workflows/twofish.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/workspace.yml b/.github/workflows/workspace.yml
index bd3ba719..87de3841 100644
--- a/.github/workflows/workspace.yml
+++ b/.github/workflows/workspace.yml
@@ -9,6 +9,11 @@ on:
     paths-ignore:
       - README.md
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   clippy:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/xtea.yml b/.github/workflows/xtea.yml
index ac9937c8..2b2e9195 100644
--- a/.github/workflows/xtea.yml
+++ b/.github/workflows/xtea.yml
@@ -17,6 +17,11 @@ env:
   CARGO_INCREMENTAL: 0
   RUSTFLAGS: "-Dwarnings"
 
+# Cancels CI jobs when new commits are pushed to a PR branch
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
 jobs:
   build:
     runs-on: ubuntu-latest