diff --git a/projects/libcss/Dockerfile b/projects/libcss/Dockerfile
new file mode 100644
index 000000000000..26758d4b27d2
--- /dev/null
+++ b/projects/libcss/Dockerfile
@@ -0,0 +1,26 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+
+FROM gcr.io/oss-fuzz-base/base-builder
+
+RUN apt-get update && apt-get install -y python3-pip ninja-build
+RUN pip3 install meson
+RUN git clone --depth 1 https://gitlab.collabora.com/libcss/libcss.git libcss
+RUN git clone --depth 1 https://gitlab.collabora.com/libcss/libcss-tests.git libcss-tests
+WORKDIR libcss
+COPY build.sh $SRC/
+
+
diff --git a/projects/libcss/build.sh b/projects/libcss/build.sh
new file mode 100644
index 000000000000..6e1379daa083
--- /dev/null
+++ b/projects/libcss/build.sh
@@ -0,0 +1,33 @@
+#!/bin/bash -eu
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+################################################################################
+
+# Build libcss and dependencies
+cd $SRC/libcss
+cd build
+meson setup .. --default-library=static
+ninja -j$(nproc)
+ninja install
+cd ../..
+
+
+# Set executable permissions for fuzzer build scripts
+chmod +x $SRC/libcss/test/fuzzers/build_google_oss_fuzzers.sh
+chmod +x $SRC/libcss/test/fuzzers/build_seed_corpus.sh
+
+# Build fuzzers and seed corpus
+$SRC/libcss/test/fuzzers/build_google_oss_fuzzers.sh
+$SRC/libcss/test/fuzzers/build_seed_corpus.sh
\ No newline at end of file
diff --git a/projects/libcss/project.yaml b/projects/libcss/project.yaml
new file mode 100644
index 000000000000..7da8d55f6e50
--- /dev/null
+++ b/projects/libcss/project.yaml
@@ -0,0 +1,12 @@
+homepage: "https://gitlab.collabora.com/libcss"
+primary_contact: "aaron.boxer@collabora.com"
+language: c
+fuzzing_engines:
+  - libfuzzer
+  - afl
+  - honggfuzz
+sanitizers:
+  - address
+  - memory
+  - undefined
+main_repo: 'https://gitlab.collabora.com/libcss/libcss.git'