diff --git a/README.md b/README.md
index 6bdba8f..49574fc 100644
--- a/README.md
+++ b/README.md
@@ -184,6 +184,13 @@ Overwriting the current list of excluded file patterns is possible with this mes
 
 ### TerminalEventHandler
 
+By default callbacks on terminal history are invoked *as soon as* a command starts to execute in the terminal (they do not wait for the started command to finish, the callback may even run in paralell with the command).
+
+If you want to wait for them and invoke your callbacks *after* the command has finished, please set the `TFW_DELAY_HISTAPPEND` envvar to `1`.
+Practically this can be done by appending an `export` to the user's `.bashrc` file from your `Dockerfile`, like so:
+
+`RUN echo "export TFW_DELAY_HISTAPPEND=1" >> /home/${AVATAO_USER}/.bashrc`
+
 Writing to the terminal:
 ```
 {