diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 00000000..c868d566
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,96 @@
+name: Testing
+
+# Trigger the workflow on push or pull request,
+# but only for the master branch
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      # Don't immediately kill all if one Python version fails
+      fail-fast: false
+      matrix:
+        python-version: ['3.8', '3.9', '3.10', '3.11']
+    env:
+      CC: mpicc
+      PETSC_DIR: ${{ github.workspace }}/petsc
+      PETSC_ARCH: default
+      PETSC_CONFIGURE_OPTIONS: --with-debugging=1 --with-shared-libraries=1 --with-c2html=0 --with-fortran-bindings=0
+      RDMAV_FORK_SAFE: 1
+    timeout-minutes: 60
+
+    steps:
+      - name: Install system dependencies
+        shell: bash
+        run: |
+          sudo apt update
+          sudo apt install build-essential mpich libmpich-dev \
+              libblas-dev liblapack-dev gfortran
+
+      - name: Set correct Python version
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Clone PETSc
+        uses: actions/checkout@v4
+        with:
+          repository: firedrakeproject/petsc
+          path: ${{ env.PETSC_DIR }}
+
+      - name: Build and install PETSc
+        shell: bash
+        working-directory: ${{ env.PETSC_DIR }}
+        run: |
+          ./configure ${PETSC_CONFIGURE_OPTIONS}
+          make
+
+      - name: Build and install petsc4py
+        # Remove this step when Firedrake PETSc branch is updated to support
+        # building petsc4py with Cython>=3.0
+        shell: bash
+        working-directory: ${{ env.PETSC_DIR }}/src/binding/petsc4py
+        run: |
+          pip install --upgrade pip
+          pip install --upgrade wheel 'cython<3' numpy
+          pip install --no-deps .
+
+      - name: Checkout pyop3
+        uses: actions/checkout@v4
+        with:
+          path: pyop3
+
+      - name: Install pyop3 and testing dependencies
+        shell: bash
+        working-directory: pyop3
+        run: |
+          # Gross:
+          pip install toml
+          python scripts/requirements.py build | pip install -r /dev/stdin
+          pip install --no-build-isolation .
+          python scripts/requirements.py run | pip install -r /dev/stdin
+          pip install pytest pytest-cov pytest-timeout pytest-xdist pytest-timeout
+
+      - name: Run tests
+        shell: bash
+        working-directory: pyop3
+        run: |
+          pytest \
+            --durations=200 \
+            --tb=native \
+            --cov pyop3 \
+            --timeout=480 \
+            --timeout-method=thread \
+            -o faulthandler_timeout=540 \
+            -n 12 --dist worksteal \
+            -v tests
+        timeout-minutes: 10
+
+
diff --git a/pyop3/config.py b/pyop3/config.py
index 29f14313..d5758e21 100644
--- a/pyop3/config.py
+++ b/pyop3/config.py
@@ -36,8 +36,6 @@
 import os
 from tempfile import gettempdir
 
-from loopy.target.c import CWithGNULibcTarget
-
 
 class ConfigurationError(RuntimeError):
     pass
@@ -155,5 +153,3 @@ def __setitem__(self, key, value):
 
 
 config = Configuration()
-
-target = CWithGNULibcTarget()
diff --git a/pyproject.toml b/pyproject.toml
index a6baa300..35ad9086 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,10 @@
 [build-system]
-requires = ["setuptools", "cython"]
+requires = [
+  "setuptools",
+  "cython<3",
+  "numpy",
+  "petsc4py"
+]
 build-backend = "setuptools.build_meta"
 
 [project]
@@ -7,6 +12,10 @@ name = "pyop3"
 version = "0.1"
 dependencies = [
   "pyrsistent",
+  "numpy",
+  "loopy @ git+https://github.com/firedrakeproject/loopy.git",
+  "mpi4py",
+  "petsc4py"
 ]
 
 [project.optional-dependencies]
diff --git a/scripts/requirements.py b/scripts/requirements.py
new file mode 100644
index 00000000..a0f85aea
--- /dev/null
+++ b/scripts/requirements.py
@@ -0,0 +1,11 @@
+import sys
+
+import toml
+
+pyproject = toml.load("pyproject.toml")
+if "build" in sys.argv:
+    packages = pyproject["build-system"]["requires"]
+elif "run" in sys.argv:
+    packages = pyproject["project"]["dependencies"]
+
+print("\n".join([pkg for pkg in packages if pkg != "petsc4py"]))