Add clearer JBang wrapper example

README.md

@@ -295,6 +295,9 @@ echo "JPAXAJPAXAJPAXA" >> stubs/stub-linux-arm_32
 
 See the `examples/` directory for sample applications.
 
+- [`examples/jbang-wrap`](./examples/jbang-wrap): package a JBang wrapper and ship a single executable
+- [`examples/simple-java`](./examples/simple-java): package a small Java application
+
 ## Limitations
 
 - first run pays extraction cost

examples/jbang-wrap/README.md

@@ -1,23 +1,57 @@
-# Simple JBang Example
+# JBang wrapper example
 
-This example shows how to package jbang wrapper to run
-anything jbang is capable of running.
+This example shows how to package a JBang wrapper with `jpaxa` so you can ship a single executable that can run a JBang app on the target machine.
 
-## Steps
+## What it demonstrates
 
-1. Compile the Java application:
-   ```bash
-   javac Hello.java
-   ```
+- wrapping an app directory that already contains the JBang wrapper scripts
+- using `{{jpaxa}}` to locate the extracted wrapper at runtime
+- producing a single self-extracting executable instead of asking users to unpack files manually
 
-2. Package it with jpaxa:
-   ```bash
-   jpaxa . -- "{{app}}/jbang" "env@jbangdev"
-   ```
+## Prepare the wrapper
 
-3. Run the packaged executable:
-   ```bash
-   ./jbang-wrap additional args
-   ```
+From this directory, create the JBang wrapper files:
 
-Note: On Windows, use `hello.exe` as the output name.
+```bash
+jbang wrapper install -d .
+```
+
+That gives you files such as `jbang`, `jbang.cmd`, and `jbang.ps1` inside this example directory.
+
+## Build the executable
+
+### macOS / Linux
+
+```bash
+jpaxa \
+  --input . \
+  --output jbang-wrap \
+  -- "{{jpaxa}}/jbang" "env@jbangdev"
+```
+
+### Windows
+
+```bash
+jpaxa \
+  --input . \
+  --output jbang-wrap.exe \
+  -- "{{jpaxa}}/jbang.cmd" "env@jbangdev"
+```
+
+## Run it
+
+```bash
+./jbang-wrap
+```
+
+You should see the output from `env@jbangdev`, executed through the extracted JBang wrapper bundled in the executable.
+
+## Why this example matters
+
+This is one of the nicest `jpaxa` use cases:
+
+- author a tool with JBang
+- bundle the wrapper once
+- ship a single file to users
+
+No installer, no manual unzip step, and no need to explain the internal file layout to the user.