diff --git a/projects/gitpython/Dockerfile b/projects/gitpython/Dockerfile
index e997b98245df..6d1bcac505d7 100644
--- a/projects/gitpython/Dockerfile
+++ b/projects/gitpython/Dockerfile
@@ -13,6 +13,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 FROM gcr.io/oss-fuzz-base/base-builder-python
-RUN git clone https://github.com/gitpython-developers/gitpython gitpython
+RUN git clone https://github.com/gitpython-developers/gitpython gitpython \
+    && python3 -m pip install --upgrade pip;
+
+RUN mkdir -p $SRC/seed_data \
+    && git clone --depth 1 https://github.com/DaveLak/oss-fuzz-inputs.git oss-fuzz-inputs \
+    && rsync -avc oss-fuzz-inputs/gitpython/ $SRC/seed_data/ \
+    && rm -rf oss-fuzz-inputs;
+
+RUN git clone --depth 1 https://github.com/google/fuzzing fuzzing \
+    && cat fuzzing/dictionaries/utf8.dict \
+      >> $SRC/seed_data/__base.dict \
+    && rm -rf fuzzing;
+
 COPY *.sh *py $SRC/
 WORKDIR $SRC/gitpython
diff --git a/projects/gitpython/build.sh b/projects/gitpython/build.sh
index 0f26fbc3c229..cfb5069491ef 100644
--- a/projects/gitpython/build.sh
+++ b/projects/gitpython/build.sh
@@ -14,9 +14,32 @@
 # limitations under the License.
 #
 ################################################################################
-pip3 install .
+python3 -m pip install .
+
+# Directory to look in for dictionaries, options files, and seed corpa:
+SEED_DATA_DIR="$SRC/seed_data"
+
+find $SEED_DATA_DIR \( -name '*_seed_corpus.zip' -o -name '*.options' -o -name '*.dict' \) \
+  ! \( -name '__base.*' \) -exec printf 'Copying: %s\n' {} \; \
+  -exec chmod a-x {} \; \
+  -exec cp {} "$OUT" \;
 
 # Build fuzzers in $OUT.
-for fuzzer in $(find $SRC -name 'fuzz_*.py'); do
-  compile_python_fuzzer $fuzzer
+find "$SRC" -maxdepth 1 -name 'fuzz_*.py' -print0 | while IFS= read -r -d $'\0' fuzz_harness; do
+  compile_python_fuzzer "$fuzz_harness"
+
+  common_base_dictionary_filename="$SEED_DATA_DIR/__base.dict"
+  if [[ -r "$common_base_dictionary_filename" ]]; then
+    # Strip the `.py` extension from the filename and replace it with `.dict`.
+    fuzz_harness_dictionary_filename="$(basename "$fuzz_harness" .py).dict"
+    output_file="$OUT/$fuzz_harness_dictionary_filename"
+
+    printf 'Appending %s to %s\n' "$common_base_dictionary_filename" "$output_file"
+    # Ensure a newline is added at the end of the file before appending,
+    # but only if the file already exists and is not empty.
+    if [[ -s "$output_file" ]]; then
+      echo >> "$output_file"
+    fi
+    cat "$common_base_dictionary_filename" >> "$output_file"
+  fi
 done
diff --git a/projects/gitpython/fuzz_config.py b/projects/gitpython/fuzz_config.py
index 62b43ae347bb..9760eed799fd 100644
--- a/projects/gitpython/fuzz_config.py
+++ b/projects/gitpython/fuzz_config.py
@@ -12,31 +12,37 @@
 # 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.
+import atheris
 import sys
 import io
-import atheris
+from configparser import MissingSectionHeaderError, ParsingError
 
-import configparser
-from git import GitConfigParser
+with atheris.instrument_imports():
+  from git import GitConfigParser
 
 
 def TestOneInput(data):
-  fdp = atheris.FuzzedDataProvider(data)
   sio = io.BytesIO(data)
   sio.name = "/tmp/fuzzconfig.config"
   git_config = GitConfigParser(sio)
   try:
     git_config.read()
-  except configparser.MissingSectionHeaderError:
-    pass
-  except configparser.ParsingError:
-    pass
-  except UnicodeDecodeError:
-    pass
+  except (MissingSectionHeaderError, ParsingError, UnicodeDecodeError):
+    return -1  # Reject inputs raising expected exceptions
+  except (IndexError, ValueError) as e:
+    if isinstance(e, IndexError) and "string index out of range" in str(e):
+      # Known possibility that might be patched
+      # See: https://github.com/gitpython-developers/GitPython/issues/1887
+      pass
+    elif isinstance(e, ValueError) and "embedded null byte" in str(e):
+      # The `os.path.expanduser` function, which does not accept strings
+      # containing null bytes might raise this.
+      return -1
+    else:
+      raise e  # Raise unanticipated exceptions as they might be bugs
 
 
 def main():
-  atheris.instrument_all()
   atheris.Setup(sys.argv, TestOneInput)
   atheris.Fuzz()
 
diff --git a/projects/gitpython/fuzz_tree.py b/projects/gitpython/fuzz_tree.py
index 8f0fc1a39e04..e1c0fe537993 100644
--- a/projects/gitpython/fuzz_tree.py
+++ b/projects/gitpython/fuzz_tree.py
@@ -12,13 +12,15 @@
 # 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.
+import atheris
 import io
 import sys
+import os
 import shutil
-import atheris
 
-from git.objects import Tree
-from git import Repo
+with atheris.instrument_imports():
+  from git.objects import Tree
+  from git.repo import Repo
 
 
 def TestOneInput(data):
@@ -45,11 +47,10 @@ def TestOneInput(data):
   try:
     fuzz_tree._deserialize(io.BytesIO(data))
   except IndexError:
-    pass
+    return -1
 
 
 def main():
-  atheris.instrument_all()
   atheris.Setup(sys.argv, TestOneInput)
   atheris.Fuzz()