diff --git a/part3/improve2/oss-fuzz.diff b/part3/improve2/oss-fuzz.diff
new file mode 100644
index 0000000..9812193
--- /dev/null
+++ b/part3/improve2/oss-fuzz.diff
@@ -0,0 +1,26 @@
+diff --git a/infra/helper.py b/infra/helper.py
+index edf073458..a595dbfbb 100755
+--- a/infra/helper.py
++++ b/infra/helper.py
+@@ -1448,6 +1448,8 @@ def run_fuzzer(args):
+       '%s:/out' % args.project.out,
+       '-t',
+       BASE_RUNNER_IMAGE,
++      'timeout',
++      '14400',
+       'run_fuzzer',
+       args.fuzzer_name,
+   ] + args.fuzzer_args)
+diff --git a/projects/libpng/Dockerfile b/projects/libpng/Dockerfile
+index 6f281cd55..3017d4404 100644
+--- a/projects/libpng/Dockerfile
++++ b/projects/libpng/Dockerfile
+@@ -19,6 +19,7 @@ RUN apt-get update && \
+     apt-get install -y make autoconf automake libtool zlib1g-dev
+ 
+ RUN git clone --depth 1 https://github.com/madler/zlib.git
+-RUN git clone --depth 1 https://github.com/pnggroup/libpng.git
++RUN git clone --depth 1 --branch BRANCH_TO_CHECKOUT https://github.com/SekoiaTree/libpng.git
++#FUZZ_SEED_DISABLE RUN sed -i 's/libpng_read_fuzzer_seed_corpus\.zip/libpng_read_fuzzer_seed_corpus.zip.disabled/g' $SRC/build.sh
+ RUN cp libpng/contrib/oss-fuzz/build.sh $SRC
+ WORKDIR libpng
diff --git a/part3/improve2/run.improve2.sh b/part3/improve2/run.improve2.sh
new file mode 100755
index 0000000..9882752
--- /dev/null
+++ b/part3/improve2/run.improve2.sh
@@ -0,0 +1,16 @@
+#!/bin/bash
+COMMIT_HASH="153dfb75531c0b73499cef9380357fe0c49a3968"
+
+git clone https://github.com/SekoiaTree/oss-fuzz.git oss-fuzz-i1
+cd oss-fuzz-i1
+git checkout $COMMIT_HASH
+sed -i 's/BRANCH_TO_CHECKOUT/improve2/g' projects/libpng/Dockerfile
+python3 infra/helper.py build_image --pull libpng
+python3 infra/helper.py build_fuzzers --clean libpng
+
+mkdir -p build/out/corpus
+python3 infra/helper.py run_fuzzer libpng libpng_read_fuzzer --corpus-dir build/out/corpus
+python3 infra/helper.py build_fuzzers --sanitizer coverage libpng
+# no-serve: to exit immediately
+# port: in case port 8008 is already allocated, even with no-serve it fails otherwise...
+python3 infra/helper.py coverage libpng --corpus-dir build/out/corpus --fuzz-target libpng_read_fuzzer --no-serve --port 9531