diff --git a/R/zzz.R b/R/zzz.R
index 0f43fac..35d8b98 100644
--- a/R/zzz.R
+++ b/R/zzz.R
@@ -2,3 +2,12 @@
 #' @importFrom stats setNames
 NULL
 
+.onAttach <- function(libname, pkgname) {
+    if (!torch::torch_is_installed()) {
+        packageStartupMessage(
+            "torch backend (Lantern) is not installed.\n",
+            "Run torch::install_torch() to complete setup."
+        )
+    }
+}
+
diff --git a/README.md b/README.md
index 43c15db..d549af6 100644
--- a/README.md
+++ b/README.md
@@ -6,12 +6,22 @@ Native R torch implementation of OpenAI Whisper for speech-to-text transcription
 
 ```r
 install.packages("whisper")
+torch::install_torch()  # one-time: downloads the C++ backend
 ```
 
 Or install the development version from GitHub:
 
 ```r
 remotes::install_github("cornball-ai/whisper")
+torch::install_torch()
+```
+
+`{whisper}` uses `{torch}` for inference. After installing the R package, `install_torch()` downloads the compiled C++ libraries (Lantern). You only need to run it once.
+
+**littler/r2u users:** If `install_torch()` fails with a permissions error, torch was installed to the system library. Use sudo for the one-time Lantern download:
+
+```bash
+sudo r -e 'torch::install_torch()'
 ```
 
 ## Quick Start