+- **`GENERATOR`:**
+ The name of the generator program (default: `⛩️📰 书社`).
+
+- **`VERSION`:**
+ The current version of `GENERATOR` (default: derived from the current
+ git tag/branch/commit).
+
+- **`SRCREV`:**
+ The current version of the source files (default: derived from the
+ current git tag/branch/commit).
+