diff --git a/.travis.yml b/.travis.yml
index 5481a0d..5e5f392 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ os:
 - osx
 env:
   matrix:
+  - CONDA_ENV=3.8
   - CONDA_ENV=3.7
   - CONDA_ENV=3.6
 sudo: false
diff --git a/README.rst b/README.rst
index 0f2be1c..752c32b 100644
--- a/README.rst
+++ b/README.rst
@@ -1,6 +1,8 @@
 BMI for Python
 ==============
 
+Python bindings for the CSDMS `Basic Model Interface <https://bmi-spec.readthedocs.io>`_.
+
 Install
 -------
 
@@ -17,6 +19,13 @@ with conda from the *conda-forge* channel,
 
   $ conda install bmipy -c conda-forge
 
+To build and install *bmipy* from source,
+
+.. code-block:: bash
+
+  $ git clone https://github.com/csdms/bmi-python
+  $ cd bmi-python
+  $ pip install .
 
 Usage
 -----
@@ -30,3 +39,7 @@ Usage
 
       def initialize(self, config_file):
           # Your implementation goes here
+
+A complete sample implementation is given in the
+https://github.com/csdms/bmi-example-python
+repository.
diff --git a/bmipy/bmi.py b/bmipy/bmi.py
index d594a4f..c4841d6 100644
--- a/bmipy/bmi.py
+++ b/bmipy/bmi.py
@@ -41,6 +41,17 @@ def update(self) -> None:
         """
         ...
 
+    @abstractmethod
+    def update_until(self, time: float) -> None:
+        """Advance model state until the given time.
+
+        Parameters
+        ----------
+        time : float
+            A model time later than the current model time.
+        """
+        ...
+
     @abstractmethod
     def finalize(self) -> None:
         """Perform tear-down tasks for the model.
@@ -62,6 +73,28 @@ def get_component_name(self) -> str:
         """
         ...
 
+    @abstractmethod
+    def get_input_item_count(self) -> int:
+        """Count of a model's input variables.
+
+        Returns
+        -------
+        int
+          The number of input variables.
+        """
+        ...
+
+    @abstractmethod
+    def get_output_item_count(self) -> int:
+        """Count of a model's output variables.
+
+        Returns
+        -------
+        int
+          The number of output variables.
+        """
+        ...
+
     @abstractmethod
     def get_input_var_names(self) -> Tuple[str]:
         """List of a model's input variables.
@@ -621,6 +654,24 @@ def get_grid_edge_nodes(self, grid: int, edge_nodes: np.ndarray) -> np.ndarray:
         """
         ...
 
+    @abstractmethod
+    def get_grid_face_edges(self, grid: int, face_edges: np.ndarray) -> np.ndarray:
+        """Get the face-edge connectivity.
+
+        Parameters
+        ----------
+        grid : int
+            A grid identifier.
+        face_edges : ndarray of int
+            A numpy array to place the face-edge connectivity.
+
+        Returns
+        -------
+        ndarray of int
+            The input numpy array that holds the face-edge connectivity.
+        """
+        ...
+
     @abstractmethod
     def get_grid_face_nodes(self, grid: int, face_nodes: np.ndarray) -> np.ndarray:
         """Get the face-node connectivity.
diff --git a/setup.py b/setup.py
index 0513763..27df8a9 100644
--- a/setup.py
+++ b/setup.py
@@ -18,6 +18,7 @@
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: Implementation :: CPython",
         "Topic :: Scientific/Engineering :: Physics",
     ],
diff --git a/tests/test_bmipy.py b/tests/test_bmipy.py
index 9527458..d4bad78 100644
--- a/tests/test_bmipy.py
+++ b/tests/test_bmipy.py
@@ -61,6 +61,12 @@ def set_value_at_indices(self, var_name, src, indices):
     def get_component_name(self):
         pass
 
+    def get_input_item_count(self):
+        pass
+
+    def get_output_item_count(self):
+        pass
+
     def get_input_var_names(self):
         pass
 
@@ -106,6 +112,9 @@ def get_grid_face_count(self, grid):
     def get_grid_face_nodes(self, grid, face_nodes):
         pass
 
+    def get_grid_face_edges(self, grid, face_edges):
+        pass
+
     def get_grid_node_count(self, grid):
         pass