diff --git a/.devcontainer/devcontainer.bashrc b/.devcontainer/devcontainer.bashrc
index 1bd9398..2812baa 100644
--- a/.devcontainer/devcontainer.bashrc
+++ b/.devcontainer/devcontainer.bashrc
@@ -4,6 +4,7 @@
 source /opt/conda/etc/profile.d/conda.sh
 conda activate prd
 source <(yardl completion bash)
+source <(just --completions bash)
 
 if [[ "${BASH_ENV:-}" == "$(readlink -f "${BASH_SOURCE[0]:-}")" ]]; then
     # We don't want subshells to unnecessarily source this again.
diff --git a/.devcontainer/devcontainer.json b/.devcontainer/devcontainer.json
index 6a0e73f..cc2ee7d 100644
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -109,6 +109,7 @@
         "ms-python.python",
         "ms-vscode.cmake-tools",
         "ms-vscode.cpptools",
+        "sclu1034.justfile",
         "timonwong.shellcheck",
         "twxs.cmake"
       ]
diff --git a/data/download-data.sh b/data/download-data.sh
index 83a7210..da5ea84 100755
--- a/data/download-data.sh
+++ b/data/download-data.sh
@@ -1,6 +1,10 @@
 #!/bin/bash
 
+set -euo pipefail
+
 # Check if azcopy is installed
+cd "$(dirname "$0")"
+
 if ! command -v azcopy &> /dev/null
 then
     wget -O azcopy.tar.gz https://aka.ms/downloadazcopy-v10-linux
diff --git a/environment.yml b/environment.yml
index c9bea3a..15cde55 100644
--- a/environment.yml
+++ b/environment.yml
@@ -5,13 +5,14 @@ channels:
 dependencies:
   - bash-completion>=2.11
   - cmake>=3.21.3
-  - fmt>=8.1.1
   - compilers
+  - fmt>=8.1.1
+  - gh=2.38.0
   - h5py>=3.7.0
   - hdf5>=1.12.1
   - howardhinnant_date>=3.0.1
   - ipykernel>=6.19.2
-  - gh=2.38.0
+  - just=1.16.0
   - ninja>=1.11.0
   - nlohmann_json>=3.11.2
   - numpy>=1.24.3
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..aa42d36
--- /dev/null
+++ b/justfile
@@ -0,0 +1,21 @@
+set shell := ['bash', '-ceuo', 'pipefail']
+
+default: build
+
+@download-test-data:
+    data/download-data.sh
+
+@ensure-build-dir:
+    mkdir -p cpp/build
+
+@generate:
+    cd PETSIRD/model; \
+    yardl generate
+
+@configure: generate ensure-build-dir
+    cd cpp/build; \
+    cmake -GNinja ..
+
+@build: configure
+    cd cpp/build; \
+    ninja