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+# gencert
+
+A thing that generates certificates. Since https://letsencrypt.org/ is
+also a thing, you should probably use that instead. Still, gencert can
+be useful to do PKI on things that only live on your LAN.
+
+## Examples
+
+```shell
+# Generate a self-signed certificate.
+# This generates ~/out/my-ca.crt and ~/out/my-ca.key.
+$ gencert             \
+    -c US             \
+    -o example.com    \
+    -cn 'My CA'       \
+    -d $((100 * 24))h \
+    -out ~/out/my-ca
+
+# Generate a normal certificate.
+# This reads ~/out/my-ca.crt and ~/out/my-ca.key, and generates
+# ~/out/my-site.crt and ~/my-site.key.
+$ gencert                \
+    -ca ~/out/my-ca      \
+    -c US                \
+    -o example.com       \
+    -cn 'My Server'      \
+    -d $((10 * 24))h     \
+    -dns www.example.com \
+    -out ~/out/my-site
+```