diff --git a/CMakeLists.txt b/CMakeLists.txt
index 893baf2951d7136d7b291e4fce5c1ac827167022..e9c24112daefb6350d78de46f765828eab78a7a8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -729,8 +729,6 @@ endif()
 
 
 set(ZIG_BUILD_ARGS
-  --zig-lib-dir "${PROJECT_SOURCE_DIR}/lib"
-
   "-Dversion-string=${RESOLVED_ZIG_VERSION}"
   "-Dtarget=${ZIG_TARGET_TRIPLE}"
   "-Dcpu=${ZIG_TARGET_MCPU}"
diff --git a/ci/aarch64-freebsd-debug.sh b/ci/aarch64-freebsd-debug.sh
index f84a683771b456066ce5c7997b12bae71aac27bb..f1e53270618c5954a0554934a4dd90e81e8d5e3f 100755
--- a/ci/aarch64-freebsd-debug.sh
+++ b/ci/aarch64-freebsd-debug.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 stage3-debug/bin/zig build \
diff --git a/ci/aarch64-freebsd-release.sh b/ci/aarch64-freebsd-release.sh
index e008d4ee81fb11bdeac967f93965d7bffb754c5d..0f5a949b7a89c0256f4c9d4d8e85607756b88c00 100755
--- a/ci/aarch64-freebsd-release.sh
+++ b/ci/aarch64-freebsd-release.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.
diff --git a/ci/aarch64-linux-debug.sh b/ci/aarch64-linux-debug.sh
index 5ee0a33c1ccce4272f0a26a833c4cee56e5b7db5..c8497814fdc6688e6b1d9f6d307afbe9bbd0ac88 100755
--- a/ci/aarch64-linux-debug.sh
+++ b/ci/aarch64-linux-debug.sh
@@ -42,6 +42,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -49,7 +52,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-superhtml \
   --test-timeout 3m
 
diff --git a/ci/aarch64-linux-release.sh b/ci/aarch64-linux-release.sh
index ae5203195d5a17d6fdd4b9970b3802c3d4115ca1..d6bf710555d13145ea7978d152561e0cc2f87d9b 100755
--- a/ci/aarch64-linux-release.sh
+++ b/ci/aarch64-linux-release.sh
@@ -42,6 +42,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -49,7 +52,6 @@ stage3-release/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-superhtml \
   --test-timeout 3m
 
diff --git a/ci/aarch64-macos-debug.sh b/ci/aarch64-macos-debug.sh
index dd959ef0c97d306d3f79a40d61d0eba87ae5c268..226b3109eafa9e8de169999b52fcd748ddb7c088 100755
--- a/ci/aarch64-macos-debug.sh
+++ b/ci/aarch64-macos-debug.sh
@@ -43,9 +43,11 @@ cmake .. \
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-macos-sdk \
   -Dstatic-llvm \
   -Dskip-spirv \
diff --git a/ci/aarch64-macos-release.sh b/ci/aarch64-macos-release.sh
index 5f2012d268fd097215113c760320092aba529ad0..b1b431f257fd867bf2bacea31dc63dff3d4a3acb 100755
--- a/ci/aarch64-macos-release.sh
+++ b/ci/aarch64-macos-release.sh
@@ -43,8 +43,10 @@ cmake .. \
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-macos-sdk \
   -Dstatic-llvm \
   -Dskip-spirv \
diff --git a/ci/aarch64-netbsd-debug.sh b/ci/aarch64-netbsd-debug.sh
index 1fedad9875d77822bd5473b3603248ecaece2314..a7d7d3e97920a95ff4006792c1bea005bc648583 100755
--- a/ci/aarch64-netbsd-debug.sh
+++ b/ci/aarch64-netbsd-debug.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 stage3-debug/bin/zig build \
diff --git a/ci/aarch64-netbsd-release.sh b/ci/aarch64-netbsd-release.sh
index db59d529e928f0059f664bd3557cde654d803f92..e0a4c9aaa03f87770b013be6aaf92ffddc6d2bbc 100755
--- a/ci/aarch64-netbsd-release.sh
+++ b/ci/aarch64-netbsd-release.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.
diff --git a/ci/aarch64-windows.ps1 b/ci/aarch64-windows.ps1
index c711127a61fd0a8c48617a67199757fb2c3a7ae1..3268dfd1e4eec456d247780beab3ae2542eb6897 100644
--- a/ci/aarch64-windows.ps1
+++ b/ci/aarch64-windows.ps1
@@ -4,7 +4,6 @@ $MCPU = "baseline"
 $ZIG_LLVM_CLANG_LLD_URL = "https://ziglang.org/deps/$ZIG_LLVM_CLANG_LLD_NAME.zip"
 $PREFIX_PATH = "$(Get-Location)\..\$ZIG_LLVM_CLANG_LLD_NAME"
 $ZIG = "$PREFIX_PATH\bin\zig.exe"
-$ZIG_LIB_DIR = "$(Get-Location)\lib"
 $ZSF_MAX_RSS = if ($Env:ZSF_MAX_RSS) { $Env:ZSF_MAX_RSS } else { 0 }
 
 if (!(Test-Path "..\$ZIG_LLVM_CLANG_LLD_NAME.zip")) {
@@ -53,10 +52,12 @@ CheckLastExitCode
 ninja install
 CheckLastExitCode
 
+# Must be done after zig cc is finished.
+$Env:ZIG_LIB_DIR="$(Get-Location)\..\lib"
+
 Write-Output "Main test suite..."
 & "stage3-release\bin\zig.exe" build test docs `
   --maxrss $ZSF_MAX_RSS `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   --search-prefix "$PREFIX_PATH" `
   -Dstatic-llvm `
   -Dskip-non-native `
diff --git a/ci/loongarch64-linux-debug.sh b/ci/loongarch64-linux-debug.sh
index f980744f8d0d3f7f790e88147635691cbee720f7..b3460be8fe4585bda04f9702c6d666dcf47949c5 100755
--- a/ci/loongarch64-linux-debug.sh
+++ b/ci/loongarch64-linux-debug.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -47,7 +50,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 stage3-debug/bin/zig build \
diff --git a/ci/loongarch64-linux-release.sh b/ci/loongarch64-linux-release.sh
index 0343259929fb06d39cfeda396c326f9b0cabbba9..4c1451a09003a53cde93328d34aad08c7de272f0 100755
--- a/ci/loongarch64-linux-release.sh
+++ b/ci/loongarch64-linux-release.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -47,7 +50,6 @@ stage3-release/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.
diff --git a/ci/powerpc64le-linux-debug.sh b/ci/powerpc64le-linux-debug.sh
index cbdfd9f48fa7c228e499c23b93ca71879c5f8474..442a7a03c3637b95249b4273469348a418b784ce 100755
--- a/ci/powerpc64le-linux-debug.sh
+++ b/ci/powerpc64le-linux-debug.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -48,7 +51,6 @@ stage3-debug/bin/zig build test docs \
   -Dtarget=native-native-musl \
   -Dcpu=native+longcall \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 stage3-debug/bin/zig build \
diff --git a/ci/powerpc64le-linux-release.sh b/ci/powerpc64le-linux-release.sh
index 25150408a4ef2161eb171371796b229a5f768ed6..c03c1504febc9e8039a74781c091fc999dd5d9e8 100755
--- a/ci/powerpc64le-linux-release.sh
+++ b/ci/powerpc64le-linux-release.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -48,7 +51,6 @@ stage3-release/bin/zig build test docs \
   -Dtarget=native-native-musl \
   -Dcpu=native+longcall \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.
diff --git a/ci/riscv64-linux-debug.sh b/ci/riscv64-linux-debug.sh
index 631573cfec76fc58be737b087a60a52ed0b04887..f01fc2bb09d763e3dbd06abbc055148d7d1b5ba0 100755
--- a/ci/riscv64-linux-debug.sh
+++ b/ci/riscv64-linux-debug.sh
@@ -42,6 +42,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-debug/bin/zig build test-modules test-c-abi \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -50,5 +53,4 @@ stage3-debug/bin/zig build test-modules test-c-abi \
   -Dskip-single-threaded \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
diff --git a/ci/riscv64-linux-release.sh b/ci/riscv64-linux-release.sh
index 1f51b7d8c2931b4344bc05f9d7e76021ec35e590..34719e9d0d9595ff05f9d99f600b74347ddcb208 100755
--- a/ci/riscv64-linux-release.sh
+++ b/ci/riscv64-linux-release.sh
@@ -42,6 +42,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-release/bin/zig build test-modules test-c-abi \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -50,5 +53,4 @@ stage3-release/bin/zig build test-modules test-c-abi \
   -Dskip-single-threaded \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
diff --git a/ci/s390x-linux-debug.sh b/ci/s390x-linux-debug.sh
index f4d601ce4bc74fe5244b3bd596f4e75684eaefe1..3d97f9c1650189ae1f105553257dd692e94f818d 100755
--- a/ci/s390x-linux-debug.sh
+++ b/ci/s390x-linux-debug.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -47,7 +50,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 stage3-debug/bin/zig build \
diff --git a/ci/s390x-linux-release.sh b/ci/s390x-linux-release.sh
index db70925e67b6afea80b483821e0a9a47d011f4a0..a8c5a9fcb341bb616729c5ab792acff29ca3db02 100755
--- a/ci/s390x-linux-release.sh
+++ b/ci/s390x-linux-release.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # No -fqemu and -fwasmtime here as they're covered by the x86_64-linux scripts.
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
@@ -47,7 +50,6 @@ stage3-release/bin/zig build test docs \
   -Dskip-non-native \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 4m
 
 # Ensure that stage3 and stage4 are byte-for-byte identical.
diff --git a/ci/x86_64-freebsd-debug.sh b/ci/x86_64-freebsd-debug.sh
index ec8d0db1ad77db75111ad334edca9094ffc03419..c67c7bbe4d50bdd2448a83e0479ff61b65cc5a62 100755
--- a/ci/x86_64-freebsd-debug.sh
+++ b/ci/x86_64-freebsd-debug.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
@@ -51,7 +54,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-windows \
   -Dskip-darwin \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 stage3-debug/bin/zig build \
diff --git a/ci/x86_64-freebsd-release.sh b/ci/x86_64-freebsd-release.sh
index f3d50ee920e1ff5ba8cf9a128b1c4a8f32e5df0d..83c88ef5aae163deee3cebd40c1b2b1f01047930 100755
--- a/ci/x86_64-freebsd-release.sh
+++ b/ci/x86_64-freebsd-release.sh
@@ -40,6 +40,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
@@ -51,7 +54,6 @@ stage3-release/bin/zig build test docs \
   -Dskip-windows \
   -Dskip-darwin \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 # Ensure that the fuzzer at least compiles.
diff --git a/ci/x86_64-linux-debug-llvm.sh b/ci/x86_64-linux-debug-llvm.sh
index 77579c827ba9414d773afddb1c8da47a5230e518..408607dbc632d110e82cca0dadcd0980b3bebe85 100755
--- a/ci/x86_64-linux-debug-llvm.sh
+++ b/ci/x86_64-linux-debug-llvm.sh
@@ -43,6 +43,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # simultaneously test building self-hosted without LLVM and with 32-bit arm
 stage3-debug/bin/zig build \
   -Dtarget=arm-linux-musleabihf \
@@ -63,7 +66,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-darwin \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-superhtml \
   --test-timeout 12m
 
diff --git a/ci/x86_64-linux-debug.sh b/ci/x86_64-linux-debug.sh
index 690b9c3314700f6a4b48ac7bc29adfe2e90bace4..fe4450ea8e67316d5d75def9c60fb79bf6edb3c6 100755
--- a/ci/x86_64-linux-debug.sh
+++ b/ci/x86_64-linux-debug.sh
@@ -42,6 +42,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # simultaneously test building self-hosted without LLVM and with 32-bit arm
 stage3-debug/bin/zig build \
   -Dtarget=arm-linux-musleabihf \
@@ -63,7 +66,6 @@ stage3-debug/bin/zig build test docs \
   -Dskip-llvm \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-superhtml \
   --test-timeout 10m
 
diff --git a/ci/x86_64-linux-release.sh b/ci/x86_64-linux-release.sh
index 815e85bf60f497585ca2d34704c6c8bd4d0d0e89..0fbccca8d3291869b1d68e461417053524b2b109 100755
--- a/ci/x86_64-linux-release.sh
+++ b/ci/x86_64-linux-release.sh
@@ -48,6 +48,9 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 # Covers several things:
 # 1. building the compiler without LLVM
 # 2. 32-bit
@@ -66,7 +69,6 @@ stage3-release/bin/zig build test docs \
   -Dstatic-llvm \
   -Dtarget=native-native-musl \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   -Denable-superhtml \
   --test-timeout 12m
 
@@ -120,6 +122,5 @@ stage3/bin/zig build -p stage4 \
   -Dstatic-llvm \
   -Dtarget=native-native-musl \
   -Dno-lib \
-  --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib"
+  --search-prefix "$PREFIX"
 stage4/bin/zig test ../test/behavior.zig
diff --git a/ci/x86_64-netbsd-debug.sh b/ci/x86_64-netbsd-debug.sh
index 3755131c6d1a815ecf1e1392f1e14be759af0ecb..ef16be259f9a5c692d63e094f974c81ee4e0e62d 100755
--- a/ci/x86_64-netbsd-debug.sh
+++ b/ci/x86_64-netbsd-debug.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 stage3-debug/bin/zig build \
diff --git a/ci/x86_64-netbsd-release.sh b/ci/x86_64-netbsd-release.sh
index 2a3dde40bd6f28f4c2ccec953307a29178d79d9d..f9fc7d6aea7fa0ed44223544052dd084a06996fd 100755
--- a/ci/x86_64-netbsd-release.sh
+++ b/ci/x86_64-netbsd-release.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 # Ensure that the fuzzer at least compiles.
diff --git a/ci/x86_64-openbsd-debug.sh b/ci/x86_64-openbsd-debug.sh
index e85befacfbf653af9d650a898effee6c860cda05..3aac9c636bc642dca609d562c6f721ce6cce8665 100755
--- a/ci/x86_64-openbsd-debug.sh
+++ b/ci/x86_64-openbsd-debug.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-debug/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 stage3-debug/bin/zig build \
diff --git a/ci/x86_64-openbsd-release.sh b/ci/x86_64-openbsd-release.sh
index ea9c44df11318118c0dbd7cc1a01838adc2a0116..76dd9a8b9c0a41efe1a89a21a7125f56f6066d44 100755
--- a/ci/x86_64-openbsd-release.sh
+++ b/ci/x86_64-openbsd-release.sh
@@ -40,12 +40,14 @@ unset CXX
 
 ninja install
 
+# Must be done after zig cc is finished.
+export ZIG_LIB_DIR="$PWD/../lib"
+
 stage3-release/bin/zig build test docs \
   --maxrss ${ZSF_MAX_RSS:-0} \
   -Dstatic-llvm \
   -Dskip-non-native \
   --search-prefix "$PREFIX" \
-  --zig-lib-dir "$PWD/../lib" \
   --test-timeout 2m
 
 # Ensure that the fuzzer at least compiles.
diff --git a/ci/x86_64-windows-debug.ps1 b/ci/x86_64-windows-debug.ps1
index a00f6812e0382c5257cf00ae22cd7dd0de3d277a..fa416bf3ff1207dc26c6ebf497608940d8fc52e7 100644
--- a/ci/x86_64-windows-debug.ps1
+++ b/ci/x86_64-windows-debug.ps1
@@ -2,7 +2,6 @@ $TARGET = "x86_64-windows-gnu"
 $MCPU = "baseline"
 $PREFIX_PATH = "$($Env:USERPROFILE)\deps\zig+llvm+lld+clang-$TARGET-0.17.0-dev.203+073889523"
 $ZIG = "$PREFIX_PATH\bin\zig.exe"
-$ZIG_LIB_DIR = "$(Get-Location)\lib"
 $ZSF_MAX_RSS = if ($Env:ZSF_MAX_RSS) { $Env:ZSF_MAX_RSS } else { 0 }
 
 function CheckLastExitCode {
@@ -42,10 +41,12 @@ CheckLastExitCode
 ninja install
 CheckLastExitCode
 
+# Must be done after zig cc is finished.
+$Env:ZIG_LIB_DIR="$(Get-Location)\..\lib"
+
 Write-Output "Main test suite..."
 stage3-debug\bin\zig build test docs `
   --maxrss $ZSF_MAX_RSS `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   --search-prefix "$PREFIX_PATH" `
   -Dstatic-llvm `
   -Dskip-non-native `
@@ -56,7 +57,6 @@ CheckLastExitCode
 
 Write-Output "Build x86_64-windows-msvc behavior tests using the C backend..."
 stage3-debug\bin\zig build-obj `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   -ofmt=c `
   -OReleaseSmall `
   --name compiler_rt `
@@ -67,7 +67,6 @@ stage3-debug\bin\zig build-obj `
 CheckLastExitCode
 
 stage3-debug\bin\zig test `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   -ofmt=c `
   -femit-bin="behavior-x86_64-windows-msvc.c" `
   --test-no-exec `
diff --git a/ci/x86_64-windows-release.ps1 b/ci/x86_64-windows-release.ps1
index 14d06818983be638497bc190e825fcb7734c8c92..8364836291d8d57097f7a76cba93b651c88c1e94 100644
--- a/ci/x86_64-windows-release.ps1
+++ b/ci/x86_64-windows-release.ps1
@@ -2,7 +2,6 @@ $TARGET = "x86_64-windows-gnu"
 $MCPU = "baseline"
 $PREFIX_PATH = "$($Env:USERPROFILE)\deps\zig+llvm+lld+clang-$TARGET-0.17.0-dev.203+073889523"
 $ZIG = "$PREFIX_PATH\bin\zig.exe"
-$ZIG_LIB_DIR = "$(Get-Location)\lib"
 $ZSF_MAX_RSS = if ($Env:ZSF_MAX_RSS) { $Env:ZSF_MAX_RSS } else { 0 }
 
 function CheckLastExitCode {
@@ -42,10 +41,12 @@ CheckLastExitCode
 ninja install
 CheckLastExitCode
 
+# Must be done after zig cc is finished.
+$Env:ZIG_LIB_DIR="$(Get-Location)\..\lib"
+
 Write-Output "Main test suite..."
 stage3-release\bin\zig.exe build test docs `
   --maxrss $ZSF_MAX_RSS `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   --search-prefix "$PREFIX_PATH" `
   -Dstatic-llvm `
   -Dskip-non-native `
@@ -82,7 +83,6 @@ CheckLastExitCode
 
 Write-Output "Build x86_64-windows-msvc behavior tests using the C backend..."
 stage3-release\bin\zig.exe build-obj `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   -ofmt=c `
   -OReleaseSmall `
   --name compiler_rt `
@@ -93,7 +93,6 @@ stage3-release\bin\zig.exe build-obj `
 CheckLastExitCode
 
 stage3-release\bin\zig.exe test `
-  --zig-lib-dir "$ZIG_LIB_DIR" `
   -ofmt=c `
   -femit-bin="behavior-x86_64-windows-msvc.c" `
   --test-no-exec `