diff --git a/Runtime-Layout.md b/Runtime-Layout.md
new file mode 100644
index 0000000..eea409d
--- /dev/null
+++ b/Runtime-Layout.md
@@ -0,0 +1,72 @@
+# Runtime Layout
+
+## Persistent Data
+
+Recommended persistent root:
+
+```text
+/srv/romexis-data
+```
+
+Typical directories:
+
+```text
+/srv/romexis-data/romexis_images
+/srv/romexis-data/romexis_ergodata
+/srv/romexis-data/romexis_cache
+/srv/romexis-data/firebird
+```
+
+---
+
+## Romexis Container Paths
+
+```text
+/opt/romexis
+/opt/romexis/server
+/opt/romexis/sconfig
+/opt/romexis/programdata
+
+/data/romexis_images
+/data/romexis_ergodata
+/data/romexis_cache
+```
+
+---
+
+## Database Paths
+
+### MSSQL
+
+```text
+/var/opt/mssql
+/var/opt/mssql/backup
+```
+
+### Firebird
+
+```text
+/firebird/data/romexis.fdb
+```
+
+---
+
+## Restart State File
+
+Used by migration restore coordination:
+
+```text
+/data/romexis_images/.romexis_restart_state
+```
+
+---
+
+## Runtime Scripts
+
+```text
+/entrypoint.sh
+/opt/init-romexis-db.sh
+/opt/init-romexis-mssql-db.sh
+/opt/init-romexis-firebird-db.sh
+/opt/fix-keystore-alias.sh
+```