diff --git a/ci/aarch64-linux-debug.sh b/ci/aarch64-linux-debug.sh
index 47f75c4624..220aaf12d9 100644
--- a/ci/aarch64-linux-debug.sh
+++ b/ci/aarch64-linux-debug.sh
@@ -19,19 +19,18 @@ export PATH="$HOME/local/bin:$PATH"
 git fetch --unshallow || true
 git fetch --tags
 
-export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
-export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
-
-rm -rf build-debug
-mkdir build-debug
-cd build-debug
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+mkdir build-debug
+cd build-debug
+
+export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
+export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
+
 cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-debug" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
@@ -66,12 +65,9 @@ stage3-debug/bin/zig build test docs \
 # Ensure that updating the wasm binary from this commit will result in a viable build.
 stage3-debug/bin/zig build update-zig1
 
-rm -rf ../build-new
 mkdir ../build-new
 cd ../build-new
 
-export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
-export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
 export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
 
diff --git a/ci/aarch64-linux-release.sh b/ci/aarch64-linux-release.sh
index a41255b454..69eed679e3 100644
--- a/ci/aarch64-linux-release.sh
+++ b/ci/aarch64-linux-release.sh
@@ -19,19 +19,18 @@ export PATH="$HOME/local/bin:$PATH"
 git fetch --unshallow || true
 git fetch --tags
 
-export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
-export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
-
-rm -rf build-release
-mkdir build-release
-cd build-release
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+mkdir build-release
+cd build-release
+
+export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
+export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
+
 cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-release" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
@@ -82,12 +81,9 @@ diff stage3-release/bin/zig stage4-release/bin/zig
 # Ensure that updating the wasm binary from this commit will result in a viable build.
 stage3-release/bin/zig build update-zig1
 
-rm -rf ../build-new
 mkdir ../build-new
 cd ../build-new
 
-export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
-export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
 export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
 
diff --git a/ci/aarch64-macos-debug.sh b/ci/aarch64-macos-debug.sh
index 4d44401a99..474f0c5cea 100755
--- a/ci/aarch64-macos-debug.sh
+++ b/ci/aarch64-macos-debug.sh
@@ -26,16 +26,15 @@ cd $ZIGDIR
 git fetch --unshallow || true
 git fetch --tags
 
-rm -rf build-debug
-mkdir build-debug
-cd build-debug
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+mkdir build-debug
+cd build-debug
+
 PATH="$HOME/local/bin:$PATH" cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-debug" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
diff --git a/ci/aarch64-macos-release.sh b/ci/aarch64-macos-release.sh
index e8ce56eaea..dac793075a 100755
--- a/ci/aarch64-macos-release.sh
+++ b/ci/aarch64-macos-release.sh
@@ -26,16 +26,15 @@ cd $ZIGDIR
 git fetch --unshallow || true
 git fetch --tags
 
-rm -rf build-release
-mkdir build-release
-cd build-release
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+mkdir build-release
+cd build-release
+
 PATH="$HOME/local/bin:$PATH" cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-release" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
diff --git a/ci/aarch64-windows.ps1 b/ci/aarch64-windows.ps1
index b0e7c474ca..44140506a7 100644
--- a/ci/aarch64-windows.ps1
+++ b/ci/aarch64-windows.ps1
@@ -30,17 +30,16 @@ if ((git rev-parse --is-shallow-repository) -eq "true") {
     git fetch --unshallow # `git describe` won't work on a shallow repo
 }
 
-Write-Output "Building from source..."
-Remove-Item -Path 'build-release' -Recurse -Force -ErrorAction Ignore
-New-Item -Path 'build-release' -ItemType Directory
-Set-Location -Path 'build-release'
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 $Env:ZIG_GLOBAL_CACHE_DIR="$(Get-Location)\zig-global-cache"
 $Env:ZIG_LOCAL_CACHE_DIR="$(Get-Location)\zig-local-cache"
 
+Write-Output "Building from source..."
+New-Item -Path 'build-release' -ItemType Directory
+Set-Location -Path 'build-release'
+
 # CMake gives a syntax error when file paths with backward slashes are used.
 # Here, we use forward slashes only to work around this.
 & cmake .. `
diff --git a/ci/x86_64-linux-debug.sh b/ci/x86_64-linux-debug.sh
index 81c286d428..1ef4745779 100755
--- a/ci/x86_64-linux-debug.sh
+++ b/ci/x86_64-linux-debug.sh
@@ -19,27 +19,24 @@ export PATH="$HOME/deps/wasmtime-v29.0.0-$ARCH-linux:$HOME/deps/qemu-linux-x86_6
 git fetch --unshallow || true
 git fetch --tags
 
-# Test building from source without LLVM.
-git clean -fd
-rm -rf zig-out
-cc -o bootstrap bootstrap.c
-./bootstrap
-./zig2 build -Dno-lib
-./zig-out/bin/zig test test/behavior.zig
-
-export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
-export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
-
-rm -rf build-debug
-mkdir build-debug
-cd build-debug
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+# Test building from source without LLVM.
+cc -o bootstrap bootstrap.c
+./bootstrap
+./zig2 build -Dno-lib
+./zig-out/bin/zig test test/behavior.zig
+
+mkdir build-debug
+cd build-debug
+
+export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
+export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
+
 cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-debug" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
@@ -76,12 +73,9 @@ stage3-debug/bin/zig build test docs \
 # Ensure that updating the wasm binary from this commit will result in a viable build.
 stage3-debug/bin/zig build update-zig1
 
-rm -rf ../build-new
 mkdir ../build-new
 cd ../build-new
 
-export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
-export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
 export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
 
diff --git a/ci/x86_64-linux-release.sh b/ci/x86_64-linux-release.sh
index a1041e7fb8..d6c0cc5701 100755
--- a/ci/x86_64-linux-release.sh
+++ b/ci/x86_64-linux-release.sh
@@ -19,27 +19,24 @@ export PATH="$HOME/deps/wasmtime-v29.0.0-$ARCH-linux:$HOME/deps/qemu-linux-x86_6
 git fetch --unshallow || true
 git fetch --tags
 
-# Test building from source without LLVM.
-git clean -fd
-rm -rf zig-out
-cc -o bootstrap bootstrap.c
-./bootstrap
-./zig2 build -Dno-lib
-./zig-out/bin/zig test test/behavior.zig
-
-export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
-export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
-
-rm -rf build-release
-mkdir build-release
-cd build-release
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+# Test building from source without LLVM.
+cc -o bootstrap bootstrap.c
+./bootstrap
+./zig2 build -Dno-lib
+./zig-out/bin/zig test test/behavior.zig
+
+mkdir build-release
+cd build-release
+
+export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
+export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
+
 cmake .. \
   -DCMAKE_INSTALL_PREFIX="stage3-release" \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
@@ -92,12 +89,9 @@ diff stage3-release/bin/zig stage4-release/bin/zig
 # Ensure that updating the wasm binary from this commit will result in a viable build.
 stage3-release/bin/zig build update-zig1
 
-rm -rf ../build-new
 mkdir ../build-new
 cd ../build-new
 
-export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
-export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 export CC="$ZIG cc -target $TARGET -mcpu=$MCPU"
 export CXX="$ZIG c++ -target $TARGET -mcpu=$MCPU"
 
diff --git a/ci/x86_64-macos-release.sh b/ci/x86_64-macos-release.sh
index 838952b181..30b3781915 100755
--- a/ci/x86_64-macos-release.sh
+++ b/ci/x86_64-macos-release.sh
@@ -24,24 +24,21 @@ cd $ZIGDIR
 git fetch --unshallow || true
 git fetch --tags
 
-# Test building from source without LLVM.
-git clean -fd
-rm -rf zig-out
-cc -o bootstrap bootstrap.c
-./bootstrap
-./zig2 build -Dno-lib
-./zig-out/bin/zig test test/behavior.zig
-
-rm -rf build
-mkdir build
-cd build
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 export ZIG_GLOBAL_CACHE_DIR="$PWD/zig-global-cache"
 export ZIG_LOCAL_CACHE_DIR="$PWD/zig-local-cache"
 
+# Test building from source without LLVM.
+cc -o bootstrap bootstrap.c
+./bootstrap
+./zig2 build -Dno-lib
+./zig-out/bin/zig test test/behavior.zig
+
+mkdir build
+cd build
+
 cmake .. \
   -DCMAKE_PREFIX_PATH="$PREFIX" \
   -DCMAKE_BUILD_TYPE=Release \
diff --git a/ci/x86_64-windows-debug.ps1 b/ci/x86_64-windows-debug.ps1
index 8fd4db222c..048ad3f15f 100644
--- a/ci/x86_64-windows-debug.ps1
+++ b/ci/x86_64-windows-debug.ps1
@@ -30,17 +30,16 @@ if ((git rev-parse --is-shallow-repository) -eq "true") {
     git fetch --unshallow # `git describe` won't work on a shallow repo
 }
 
-Write-Output "Building from source..."
-Remove-Item -Path 'build-debug' -Recurse -Force -ErrorAction Ignore
-New-Item -Path 'build-debug' -ItemType Directory
-Set-Location -Path 'build-debug'
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 $Env:ZIG_GLOBAL_CACHE_DIR="$(Get-Location)\zig-global-cache"
 $Env:ZIG_LOCAL_CACHE_DIR="$(Get-Location)\zig-local-cache"
 
+Write-Output "Building from source..."
+New-Item -Path 'build-debug' -ItemType Directory
+Set-Location -Path 'build-debug'
+
 # CMake gives a syntax error when file paths with backward slashes are used.
 # Here, we use forward slashes only to work around this.
 & cmake .. `
diff --git a/ci/x86_64-windows-release.ps1 b/ci/x86_64-windows-release.ps1
index 432d0649be..965fc4b578 100644
--- a/ci/x86_64-windows-release.ps1
+++ b/ci/x86_64-windows-release.ps1
@@ -30,17 +30,16 @@ if ((git rev-parse --is-shallow-repository) -eq "true") {
     git fetch --unshallow # `git describe` won't work on a shallow repo
 }
 
-Write-Output "Building from source..."
-Remove-Item -Path 'build-release' -Recurse -Force -ErrorAction Ignore
-New-Item -Path 'build-release' -ItemType Directory
-Set-Location -Path 'build-release'
-
 # Override the cache directories because they won't actually help other CI runs
 # which will be testing alternate versions of zig, and ultimately would just
 # fill up space on the hard drive for no reason.
 $Env:ZIG_GLOBAL_CACHE_DIR="$(Get-Location)\zig-global-cache"
 $Env:ZIG_LOCAL_CACHE_DIR="$(Get-Location)\zig-local-cache"
 
+Write-Output "Building from source..."
+New-Item -Path 'build-release' -ItemType Directory
+Set-Location -Path 'build-release'
+
 # CMake gives a syntax error when file paths with backward slashes are used.
 # Here, we use forward slashes only to work around this.
 & cmake .. `