diff --git a/projects/mp4parse-rust/build.sh b/projects/mp4parse-rust/build.sh
index 5af2a68c0..860a7ac43 100755
--- a/projects/mp4parse-rust/build.sh
+++ b/projects/mp4parse-rust/build.sh
@@ -16,19 +16,7 @@
 ################################################################################
 
 # Note: This project creates Rust fuzz targets exclusively
-
-export CUSTOM_LIBFUZZER_PATH="$LIB_FUZZING_ENGINE_DEPRECATED"
-export CUSTOM_LIBFUZZER_STD_CXX=c++
 PROJECT_DIR=$SRC/mp4parse-rust
-
-# Because Rust does not support sanitizers via CFLAGS/CXXFLAGS, the environment
-# variables are overridden with values from base-images/base-clang only
-
-export CFLAGS="-O1 -fno-omit-frame-pointer -gline-tables-only -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION"
-export CXXFLAGS_EXTRA="-stdlib=libc++"
-export CXXFLAGS="$CFLAGS $CXXFLAGS_EXTRA"
-export RUSTFLAGS="-Cdebuginfo=1 -Cforce-frame-pointers"
-
 cd $PROJECT_DIR/mp4parse_capi/fuzz && cargo fuzz build -O --debug-assertions
 
 mkdir $PROJECT_DIR/corpus
diff --git a/projects/serde_json/build.sh b/projects/serde_json/build.sh
index 76960bf1f..9ae8b78e4 100755
--- a/projects/serde_json/build.sh
+++ b/projects/serde_json/build.sh
@@ -16,16 +16,6 @@
 ################################################################################
 
 # Note: This project creates Rust fuzz targets exclusively
-export CUSTOM_LIBFUZZER_PATH="$LIB_FUZZING_ENGINE_DEPRECATED"
-export CUSTOM_LIBFUZZER_STD_CXX=c++
-
-# Because Rust does not support sanitizers via CFLAGS/CXXFLAGS, the environment
-# variables are overridden with values from base-images/base-clang only
-export CFLAGS="-O1 -fno-omit-frame-pointer -gline-tables-only -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION"
-export CXXFLAGS_EXTRA="-stdlib=libc++"
-export CXXFLAGS="$CFLAGS $CXXFLAGS_EXTRA"
-export RUSTFLAGS="-Cdebuginfo=1 -Cforce-frame-pointers"
-
 cd $SRC/json
 cargo fuzz build -O 
 cp fuzz/target/x86_64-unknown-linux-gnu/release/from_slice $OUT/
diff --git a/projects/wasmtime/build.sh b/projects/wasmtime/build.sh
index b4321d7f2..d2d479e0a 100755
--- a/projects/wasmtime/build.sh
+++ b/projects/wasmtime/build.sh
@@ -16,19 +16,7 @@
 ################################################################################
 
 # Note: This project creates Rust fuzz targets exclusively
-
-export CUSTOM_LIBFUZZER_PATH="$LIB_FUZZING_ENGINE_DEPRECATED"
-export CUSTOM_LIBFUZZER_STD_CXX=c++
 PROJECT_DIR=$SRC/wasmtime
-
-# Because Rust does not support sanitizers via CFLAGS/CXXFLAGS, the environment
-# variables are overridden with values from base-images/base-clang only
-
-export CFLAGS="-O1 -fno-omit-frame-pointer -gline-tables-only -DFUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION"
-export CXXFLAGS_EXTRA="-stdlib=libc++"
-export CXXFLAGS="$CFLAGS $CXXFLAGS_EXTRA"
-export RUSTFLAGS="-Cdebuginfo=1 -Cforce-frame-pointers"
-
 cd $PROJECT_DIR/fuzz && cargo fuzz build -O --debug-assertions --features binaryen
 
 FUZZ_TARGET_OUTPUT_DIR=$PROJECT_DIR/target/x86_64-unknown-linux-gnu/release