diff --git a/.github/workflows/py-code-style.yml b/.github/workflows/py-code-style.yml
index 59d2896..c9f5c61 100644
--- a/.github/workflows/py-code-style.yml
+++ b/.github/workflows/py-code-style.yml
@@ -13,6 +13,9 @@ on:
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 # A workflow run is made up of one or more jobs that can run sequentially or in parallel
 jobs:
   code-style:
@@ -37,3 +40,30 @@ jobs:
 
       - name: Check code style
         run: source .venv/bin/activate && cd ${GITHUB_WORKSPACE} && ./scripts/checkstyle.sh
+
+  # Type-check the v1 (1.22) side of the GDS compat surface.
+  code-style-gds-v1:
+    runs-on: ubuntu-latest
+
+    defaults:
+      run:
+        working-directory: python-wrapper
+
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+
+      - name: Install uv and set the Python version
+        uses: astral-sh/setup-uv@ae62891fec2bb8e7d6c99fc78c9fec3a63790f8d # v10.0.0
+        with:
+          python-version: "3.11"
+          enable-cache: true
+      - run: uv venv
+      - run: uv sync --group dev --extra pandas --extra neo4j --extra gds --extra snowflake
+      - run: uv pip install --python .venv/bin/python "graphdatascience==1.22"
+
+      - name: Check code style (GDS 1.22)
+        env:
+          UV_NO_SYNC: "1"
+          MYPY_TARGETS: "python-wrapper/src"
+        run: source .venv/bin/activate && cd ${GITHUB_WORKSPACE} && ./scripts/checkstyle.sh
+
diff --git a/justfile b/justfile
index 0330113..648d3cb 100644
--- a/justfile
+++ b/justfile
@@ -23,6 +23,21 @@ py-style:
     just py-sync
     ./scripts/makestyle.sh && ./scripts/checkstyle.sh
 
+# Run Python style checks (ruff + mypy) against a pinned `graphdatascience` version, so
+# the v1/v2 compat surface in _gds_compat is type-checked under that version. mypy is
+# scoped to `src` because the test helpers import v2-only modules (covered by the default
+# v2 gate); ruff runs on the whole tree as usual.
+# example: just py-style-gds 1.22
+py-style-gds version="1.22":
+    #!/usr/bin/env bash
+    set -e
+    just py-sync
+    uv pip install --python python-wrapper/.venv/bin/python "graphdatascience=={{version}}"
+    # UV_NO_SYNC stops `uv run` inside the style scripts from re-syncing (which would
+    # revert the pin back to the latest GDS).
+    UV_NO_SYNC=1 ./scripts/makestyle.sh
+    UV_NO_SYNC=1 MYPY_TARGETS=python-wrapper/src ./scripts/checkstyle.sh
+
 py-test:
     cd python-wrapper && uv sync --all-extras --group dev
     cd python-wrapper && uv run --group dev pytest
diff --git a/python-wrapper/src/neo4j_viz/_gds_compat.py b/python-wrapper/src/neo4j_viz/_gds_compat.py
index d09ccb8..39935e6 100644
--- a/python-wrapper/src/neo4j_viz/_gds_compat.py
+++ b/python-wrapper/src/neo4j_viz/_gds_compat.py
@@ -2,10 +2,22 @@
 
 import importlib
 import re
-from typing import Any
+from typing import Any, ContextManager, cast
 
+from graphdatascience import Graph, GraphDataScience
+from graphdatascience.procedure_surface.api.centrality.degree_endpoints import DegreeEndpoints
+from graphdatascience.procedure_surface.arrow.catalog.catalog_arrow_endpoints import (
+    CatalogArrowEndpoints,
+)
+from graphdatascience.procedure_surface.cypher.catalog.catalog_cypher_endpoints import (
+    CatalogCypherEndpoints,
+)
+from graphdatascience.session import AuraGraphDataScience
 from graphdatascience.version import __version__ as _gds_version
 
+CatalogEndpoints = CatalogArrowEndpoints | CatalogCypherEndpoints
+_GdsClient = GraphDataScience | AuraGraphDataScience
+
 
 def _parse_major(version: str) -> int:
     match = re.match(r"\s*(\d+)", version)
@@ -29,11 +41,52 @@ def _check_graph_type(G: Any) -> None:
         raise TypeError(f"`G` must be a GDS graph object ({accepted}), but got {type(G).__name__}")
 
 
-def _catalog(gds: Any) -> Any:
-    """Return the graph catalog endpoints for either client version."""
-    return gds.graph if IS_GDS_2 else gds.v2.graph
+def _catalog(gds: _GdsClient) -> CatalogEndpoints:
+    """Return the graph catalog endpoints for either client version.
+
+    In GDS v2 the catalog lives at ``gds.graph``; in v1 (1.22) the v2-compatible surface
+    is reached via ``gds.v2.graph``. The client is cast to ``Any`` for the attribute access
+    so the same code type-checks under either install (the two versions expose the catalog
+    under different attributes); the return type stays the shared concrete catalog union,
+    so callers are type-checked against whichever version is installed.
+    """
+    if IS_GDS_2:
+        return cast("CatalogEndpoints", cast(Any, gds).graph)
+    return cast("CatalogEndpoints", cast(Any, gds).v2.graph)
 
 
-def _degree_centrality(gds: Any) -> Any:
+def _degree_centrality(gds: _GdsClient) -> DegreeEndpoints:
     """Return the degree centrality endpoints for either client version."""
-    return gds.degree_centrality if IS_GDS_2 else gds.v2.degree_centrality
+    if IS_GDS_2:
+        return cast("DegreeEndpoints", cast(Any, gds).degree_centrality)
+    return cast("DegreeEndpoints", cast(Any, gds).v2.degree_centrality)
+
+
+def _project_native(
+    gds: _GdsClient, graph_name: str, node_labels: list[str], relationship_types: list[str]
+) -> ContextManager[Graph]:
+    """Native (label/type filter) projection for either client version.
+
+    In GDS v2 this is ``graph.project.native(...)`` (a property); in v1 it is the callable
+    ``graph.project(...)``. The dispatch differs, so the catalog is cast to ``Any`` here —
+    but the helper signature stays concrete, so wrong call-site arguments (e.g. passing
+    ``"*"`` instead of ``["*"]``) are still caught by mypy. The result is a context manager
+    yielding the projected graph in both versions.
+    """
+    if IS_GDS_2:
+        return cast(
+            "ContextManager[Graph]",
+            cast(Any, _catalog(gds)).project.native(graph_name, node_labels, relationship_types),
+        )
+    return cast("ContextManager[Graph]", cast(Any, _catalog(gds)).project(graph_name, node_labels, relationship_types))
+
+
+def _project_cypher(gds: _GdsClient, graph_name: str, query: str) -> ContextManager[Graph]:
+    """Cypher projection for either client version.
+
+    In GDS v2 this is ``graph.project.cypher(...)`` (a property); in v1 it is the callable
+    ``graph.project(name, query)``.
+    """
+    if IS_GDS_2:
+        return cast("ContextManager[Graph]", cast(Any, _catalog(gds)).project.cypher(graph_name, query))
+    return cast("ContextManager[Graph]", cast(Any, _catalog(gds)).project(graph_name, query))
diff --git a/python-wrapper/tests/neo4j_and_gds/test_gds.py b/python-wrapper/tests/neo4j_and_gds/test_gds.py
index dfbdeab..c3d7ae8 100644
--- a/python-wrapper/tests/neo4j_and_gds/test_gds.py
+++ b/python-wrapper/tests/neo4j_and_gds/test_gds.py
@@ -7,7 +7,7 @@
 from graphdatascience.session import AuraGraphDataScience
 
 from neo4j_viz import Node
-from neo4j_viz._gds_compat import _catalog
+from neo4j_viz._gds_compat import _catalog, _project_cypher, _project_native
 from neo4j_viz.gds import from_gds
 
 
@@ -26,9 +26,9 @@ def db_setup(gds: GraphDataScience | AuraGraphDataScience) -> Generator[None, No
 
 def project_graph(gds: GraphDataScience | AuraGraphDataScience) -> Any:
     if isinstance(gds, GraphDataScience):
-        return _catalog(gds).project("g2", "*", "*")
+        return _project_native(gds, "g2", ["*"], ["*"])
     elif isinstance(gds, AuraGraphDataScience):
-        return _catalog(gds).project("g2", "MATCH (n)–->(m) RETURN gds.graph.project.remote(n, m)")
+        return _project_cypher(gds, "g2", "MATCH (n)–->(m) RETURN gds.graph.project.remote(n, m)")
     raise Exception(f"Unsupported GDS type {type(gds)}")
 
 
diff --git a/scripts/checkstyle.sh b/scripts/checkstyle.sh
index 3bf374f..2cc5e5f 100755
--- a/scripts/checkstyle.sh
+++ b/scripts/checkstyle.sh
@@ -8,7 +8,10 @@ set -o pipefail
 
 uv run --project "${PY_PROJECT}" python -m ruff check .
 uv run --project "${PY_PROJECT}" python -m ruff format --check .
-uv run --project "${PY_PROJECT}" python -m mypy --config-file "${PY_PROJECT}/pyproject.toml" .
+# MYPY_TARGETS scopes mypy to a subset (e.g. `python-wrapper/src`) — used to type-check
+# the v1 GDS compat surface under a pinned graphdatascience without pulling in test
+# helpers that import v2-only modules.
+uv run --project "${PY_PROJECT}" python -m mypy --config-file "${PY_PROJECT}/pyproject.toml" "${MYPY_TARGETS:-.}"
 
 
 if [ "${SKIP_NOTEBOOKS:-false}" == "true" ]; then