diff --git a/.env b/.env
deleted file mode 100644
index bb1c148..0000000
--- a/.env
+++ /dev/null
@@ -1 +0,0 @@
-MODEL=
diff --git a/.gitignore b/.gitignore
deleted file mode 100644
index f633594..0000000
--- a/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-/models
diff --git a/Dockerfile b/Dockerfile
index bff352c..c30f27b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -17,7 +17,7 @@ RUN apt-get install -y \
   openmpi-bin libopenmpi-dev
 
 # Add python user.
-RUN groupadd --force "${GID}"
+RUN groupadd --force -g "${GID}" python
 RUN useradd --create-home --no-log-init -u "${UID}" -g "${GID}" python
 
 # Create build directory
diff --git a/README.md b/README.md
index 80d5448..8b4314e 100644
--- a/README.md
+++ b/README.md
@@ -1,15 +1,15 @@
 # 🌏️ ExoPlaSim Docker
 
-## Environment Variables
+## Instructions
+1. Create an ExoPlaSim model.
+2. Replace the example model in the `build` directory with your own model (keeping the filename `model.py`).
+3. Run the docker container (eg. `docker compose run -it --rm exoplasim`).
+
+## Optional Environment Variables
 
 **UID:** UID of host/guest user.
 
 **GID:** GID of host/guest user.
 
-**MODEL:** Path to model (required).
+**BUILD_DIR:** Path to build directory.
 
-## Instructions
-1. Create an ExoPlaSim model
-2. Save it somewhere with the filename `model.py`
-3. Edit the `.env` file and add the directory containing `model.py` after `MODEL=`
-4. Run the docker container (eg. `docker compose run -it --rm exoplasim`)
\ No newline at end of file
diff --git a/build/model.py b/build/model.py
new file mode 100644
index 0000000..fbce8c0
--- /dev/null
+++ b/build/model.py
@@ -0,0 +1,15 @@
+import exoplasim as exo
+
+toi700d = exo.Model(workdir="toi700d_run",modelname="TOI-700d",
+                    ncpus=8,resolution="T21",outputtype=".nc")
+
+toi700d.configure(startemp=3480.0, flux=1167.0,                           # Stellar parameters
+                  eccentricity=0.,obliquity=0.,fixedorbit=True,           # Orbital parameters
+                  synchronous=True,rotationperiod=37.426,                 # Rotation
+                  radius=1.19,gravity=11.9,aquaplanet=True,               # Bulk properties
+                  pN2=1.47*(1-360e-6),pCO2=1.47*360e-6,ozone=False,       # Atmosphere
+                  timestep=30.0,snapshots=720,physicsfilter="gp|exp|sp")  # Model dynamics
+
+toi700d.exportcfg()
+
+toi700d.run(years=10,crashifbroken=True)
diff --git a/compose.yaml b/compose.yaml
index 07601a3..1471273 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -10,4 +10,4 @@ services:
         UID: "${UID:-1001}"
         GID: "${GID:-1001}"
     volumes:
-      - "${MODEL:?error}:/build"
+      - "${BUILD_DIR:-./build}:/build"