diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index e789bbf09..59549cb70 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -20,7 +20,7 @@ repos:
         args: ["--verbose"]
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.11.11
+    rev: v0.11.13
     hooks:
       - id: ruff
         args: ["--fix", "--output-format=full"]
@@ -34,7 +34,7 @@ repos:
         files: ^docs/.*\.ipynb$
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.15.0
+    rev: v1.16.0
     hooks:
       - id: mypy
         args: [--ignore-missing-imports]
diff --git a/pixi.lock b/pixi.lock
index e4bdafec9..7b321ce9f 100644
--- a/pixi.lock
+++ b/pixi.lock
@@ -10595,7 +10595,7 @@ packages:
 - pypi: .
   name: pyfixest
   version: 0.29.0
-  sha256: 31543d41ff2468cfd50b45714058aff8a99ee2a92986ce71f79b03942bc50f33
+  sha256: 0bb19c6b3039ba36d1b8976ed88a3baefaa037dcbf6a31dc3ed5c067ead41e4d
   requires_dist:
   - scipy>=1.6
   - formulaic>=1.1.0
diff --git a/pyfixest/did/saturated_twfe.py b/pyfixest/did/saturated_twfe.py
index a5b9194a9..018631d93 100644
--- a/pyfixest/did/saturated_twfe.py
+++ b/pyfixest/did/saturated_twfe.py
@@ -454,7 +454,7 @@ def compute_period_weights(
     if include_grid:
         all_periods = sorted(df[period].unique())
         grid = pd.MultiIndex.from_product(
-            [ever_treated, all_periods], names=[cohort, period]
+            [list(ever_treated), all_periods], names=[cohort, period]
         ).to_frame(index=False)
         out = grid.merge(out, on=[cohort, period], how="left")
         out["weight"] = out["weight"].fillna(0.0)
diff --git a/pyfixest/estimation/feols_.py b/pyfixest/estimation/feols_.py
index 6ba90fbc7..f9ea19a44 100644
--- a/pyfixest/estimation/feols_.py
+++ b/pyfixest/estimation/feols_.py
@@ -222,6 +222,18 @@ class Feols:
         the _model_name_plot attribute will be modified.
     _quantile: Optional[float]
         The quantile used for quantile regression. None if not a quantile regression.
+
+    # special for did
+    _res_cohort_eventtime_dict: Optional[dict[str, Any]]
+    _yname: Optional[str]
+    _gname: Optional[str]
+    _tname: Optional[str]
+    _idname: Optional[str]
+    _att: Optional[Any]
+    test_treatment_heterogeneity: Callable[..., Any]
+    aggregate: Callable[..., Any]
+    iplot_aggregate: Callable[..., Any]
+
     """
 
     def __init__(
@@ -356,6 +368,14 @@ def __init__(
         # special for poisson
         self.deviance = None
 
+        # special for did
+        self._res_cohort_eventtime_dict: Optional[dict[str, Any]] = None
+        self._yname: Optional[str] = None
+        self._gname: Optional[str] = None
+        self._tname: Optional[str] = None
+        self._idname: Optional[str] = None
+        self._att: Optional[bool] = None
+
         # set functions inherited from other modules
         _module = import_module("pyfixest.report")
         _tmp = _module.coefplot
@@ -368,6 +388,16 @@ def __init__(
         self.summary = functools.partial(_tmp, models=[self])
         self.summary.__doc__ = _tmp.__doc__
 
+        # DiD methods - assign placeholder functions
+        def _not_implemented_did(*args, **kwargs):
+            raise NotImplementedError(
+                "This method is only available for DiD models, not for vanilla 'feols'."
+            )
+
+        self.test_treatment_heterogeneity = _not_implemented_did
+        self.aggregate = _not_implemented_did
+        self.iplot_aggregate = _not_implemented_did
+
     def prepare_model_matrix(self):
         "Prepare model matrices for estimation."
         mm_dict = model_matrix_fixest(
diff --git a/pyfixest/estimation/fepois_.py b/pyfixest/estimation/fepois_.py
index 03ed6f214..84383d2a7 100644
--- a/pyfixest/estimation/fepois_.py
+++ b/pyfixest/estimation/fepois_.py
@@ -572,7 +572,7 @@ def _check_for_separation_fe(
     """
     separation_na: set[int] = set()
     if fe is not None and not (Y > 0).all(axis=0).all():
-        Y_help = (Y > 0).astype(int).squeeze()
+        Y_help = (Y.iloc[:, 0] > 0).astype(int)
 
         # loop over all elements of fe
         for x in fe.columns:
diff --git a/pyproject.toml b/pyproject.toml
index ceb05ea2e..42e1b6634 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -225,7 +225,6 @@ docstring-code-format = true
 docstring-code-line-length = 88
 
 [tool.mypy]
-plugins = "numpy.typing.mypy_plugin"
 
 [[tool.mypy.overrides]]
 module = [