diff --git a/README.md b/README.md
index cc3b93f..054cc27 100644
--- a/README.md
+++ b/README.md
@@ -10,65 +10,17 @@ engineering point of view.
 
 Most cosplay schematics are created with Blender, CadQuery, and Inkscape.
 
-## Development
+## Build
 
-Install `uv`, and then execute
+To build the schematics for one set, install `uv`, and execute (for example, for
+`yasaka_kanako`)
 
 ``` sh
 uv sync
+uv run python3 nhf.touhou.yasaka_kanako
 ```
 
-To get a development environment, run
-``` sh
-uv venv
-```
+## Development
 
-Then, either follow the instruction to activate this venv, or install `direnv`
-and create the file
-
-``` sh
-# .envrc
-source .venv/bin/activate
-```
-
-Test the environment with `python3 -c "import nhf"`
-
-To visualize an object, create a file `visualize.py`, and run `cq-editor`:
-
-``` sh
-CQ-editor visualize.py
-```
-
-### Folder Structure
-
-- `nhf/parts/`: Ready-made parts
-- `nhf/$WORK/$CHARACTER`: Design for an individual character
-
-For each individual character, the `__init__.py` script stores the overall build
-entry point and the entry point for all unit tests.
-
-### Testing
-
-Run all tests with
-``` sh
-unittest-parallel
-```
-
-## Troubleshooting
-
-### Wayland
-
-If there is the error
-```
-X Error of failed request:  BadWindow (invalid Window parameter)
-  Major opcode of failed request:  3 (X_GetWindowAttributes)
-  Resource id in failed request:  0x3
-  Serial number of failed request:  28
-  Current serial number in output stream:  29
-```
-Export the environment variable
-
-``` sh
-export QT_QPA_PLATFORM=xcb
-```
+For developer instructions, see [development](./doc/development.md).
 
diff --git a/doc/development.md b/doc/development.md
new file mode 100644
index 0000000..69e17dc
--- /dev/null
+++ b/doc/development.md
@@ -0,0 +1,68 @@
+# Development
+
+Install `uv`, and then execute
+
+``` sh
+uv sync
+```
+
+## Environment
+
+To get a development environment, run
+``` sh
+uv venv
+```
+
+Then, either follow the instruction to activate this venv, or install `direnv`
+and create the file
+
+``` sh
+# .envrc
+source .venv/bin/activate
+```
+
+Test the environment with `python3 -c "import nhf"`
+
+To visualize an object, create a file `visualize.py`, and run `cq-editor`:
+
+``` sh
+CQ-editor visualize.py
+```
+
+## Folder Structure
+
+- `nhf/parts/`: Ready-made parts
+- `nhf/$WORK/$CHARACTER`: Design for an individual character
+
+For each individual character, the `__main__.py` script stores the overall build
+entry point and the entry point for all unit tests. Do not put build scripts in
+`__init__.py`
+
+### Testing
+
+Run all tests with
+``` sh
+unittest-parallel
+```
+
+## Troubleshooting
+
+### Wayland
+
+If there is the error
+```
+X Error of failed request:  BadWindow (invalid Window parameter)
+  Major opcode of failed request:  3 (X_GetWindowAttributes)
+  Resource id in failed request:  0x3
+  Serial number of failed request:  28
+  Current serial number in output stream:  29
+```
+Export the environment variable
+
+``` sh
+export QT_QPA_PLATFORM=xcb
+```
+
+
+
+