diff --git a/.github/workflows/mayhem.yml b/.github/workflows/mayhem.yml
new file mode 100644
index 00000000..2ac90788
--- /dev/null
+++ b/.github/workflows/mayhem.yml
@@ -0,0 +1,60 @@
+name: Mayhem
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build:
+    name: 'build mayhem fuzzing container'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@98669ae865ea3cffbcbaa878cf57c20bbf1c6c38
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@ad44023a93711e3deb337508980b4b5e9bcdc5dc
+        with:
+          context: .
+          file: mayhem/Dockerfile
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+    outputs:
+      image: ${{ steps.meta.outputs.tags }}
+
+  mayhem:
+    needs: build
+    name: 'fuzz ${{ matrix.mayhemfile }}'
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        mayhemfile:
+          - mayhem/parse.mayhemfile
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Start analysis for ${{ matrix.mayhemfile }}
+        uses: ForAllSecure/mcode-action@v1
+        with:
+          mayhem-token: ${{ secrets.MAYHEM_TOKEN }}
+          args: --image ${{ needs.build.outputs.image }} --file ${{ matrix.mayhemfile }} --duration 300
+          sarif-output: sarif
diff --git a/fuzz/.gitignore b/fuzz/.gitignore
new file mode 100644
index 00000000..1a45eee7
--- /dev/null
+++ b/fuzz/.gitignore
@@ -0,0 +1,4 @@
+target
+corpus
+artifacts
+coverage
diff --git a/fuzz/Cargo.lock b/fuzz/Cargo.lock
new file mode 100644
index 00000000..d6b40034
--- /dev/null
+++ b/fuzz/Cargo.lock
@@ -0,0 +1,887 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
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diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
new file mode 100644
index 00000000..67fadce2
--- /dev/null
+++ b/fuzz/Cargo.toml
@@ -0,0 +1,27 @@
+[package]
+name = "parcel_css-fuzz"
+version = "0.0.0"
+publish = false
+edition = "2021"
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies]
+libfuzzer-sys = "0.4"
+
+[dependencies.parcel_css]
+path = ".."
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "parse"
+path = "fuzz_targets/parse.rs"
+test = false
+doc = false
+
+[profile.release]
+debug = true
diff --git a/fuzz/fuzz_targets/parse.rs b/fuzz/fuzz_targets/parse.rs
new file mode 100644
index 00000000..fbdda9a7
--- /dev/null
+++ b/fuzz/fuzz_targets/parse.rs
@@ -0,0 +1,8 @@
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+
+use parcel_css::stylesheet::{ParserOptions, StyleSheet};
+
+fuzz_target!(|contents: &str| {
+  let _ = StyleSheet::parse(contents, ParserOptions::default());
+});
diff --git a/mayhem/Dockerfile b/mayhem/Dockerfile
new file mode 100644
index 00000000..0860366a
--- /dev/null
+++ b/mayhem/Dockerfile
@@ -0,0 +1,21 @@
+# Build Stage
+FROM ghcr.io/evanrichter/cargo-fuzz:latest as builder
+
+## Add source code to the build stage.
+ADD . /src
+WORKDIR /src
+
+RUN echo building instrumented harnesses && \
+    cargo +nightly -Z sparse-registry fuzz build --fuzz-dir fuzz && \
+    mv fuzz/target/x86_64-unknown-linux-gnu/release/parse /parse && \
+    echo done
+
+RUN echo building non-instrumented harnesses && \
+    cargo +nightly -Z sparse-registry fuzz build --fuzz-dir fuzz --disable-instrumentation && \
+    mv fuzz/target/x86_64-unknown-linux-gnu/release/parse /parse_no_inst && \
+    echo done
+
+# Package Stage
+FROM rustlang/rust:nightly
+
+COPY --from=builder /parse  /parse_no_inst /
diff --git a/mayhem/parcel.mayhemfile b/mayhem/parcel.mayhemfile
new file mode 100644
index 00000000..c3bb6e25
--- /dev/null
+++ b/mayhem/parcel.mayhemfile
@@ -0,0 +1,6 @@
+project: parcel-css
+target: parcel-css
+
+cmds:
+  - cmd: /parcel_css @@
+  - cmd: /parcel_css --nesting @@
diff --git a/mayhem/parse.mayhemfile b/mayhem/parse.mayhemfile
new file mode 100644
index 00000000..9ae27c2b
--- /dev/null
+++ b/mayhem/parse.mayhemfile
@@ -0,0 +1,7 @@
+project: parcel-css
+target: parse
+
+cmds:
+  - cmd: /parse
+  - cmd: /parse_no_inst @@
+    libfuzzer: false