diff --git a/crates/cmd_prompt/src/commands/commands/mod.rs b/crates/cmd_prompt/src/commands/commands/mod.rs
index 2ec6ea4..b73f222 100644
--- a/crates/cmd_prompt/src/commands/commands/mod.rs
+++ b/crates/cmd_prompt/src/commands/commands/mod.rs
@@ -2,6 +2,7 @@ use crate::prelude::*;
 
 mod clear;
 mod echo;
+mod set;
 mod show;
 
 pub mod prelude {
@@ -9,5 +10,5 @@ pub mod prelude {
 }
 
 pub fn plugin(app: &mut App) {
-    app.add_plugins((show::plugin, echo::plugin, clear::plugin));
+    app.add_plugins((show::plugin, echo::plugin, clear::plugin, set::plugin));
 }
diff --git a/crates/cmd_prompt/src/commands/commands/set.rs b/crates/cmd_prompt/src/commands/commands/set.rs
new file mode 100644
index 0000000..8f97505
--- /dev/null
+++ b/crates/cmd_prompt/src/commands/commands/set.rs
@@ -0,0 +1,77 @@
+use crate::prelude::*;
+
+#[derive(clap::Parser, Clone, Debug)]
+#[command(name = "set")]
+pub struct SetCmd {
+    var: String,
+    val: String,
+}
+
+fn on_msg(
+    mut reader: MessageReader<CommandMsg<SetCmd>>,
+    mut assets: ResMut<Assets<ConsoleEnvVars>>,
+    handles: Query<&ConsoleAssetHandle<ConsoleEnvVars>>,
+) {
+    for msg in reader.read() {
+        if let Ok(handle) = handles.get(msg.console_id)
+            && let Some(env_vars) = assets.get_mut(handle.id())
+        {
+            env_vars.insert(msg.command.var.clone(), msg.command.val.clone());
+        } else {
+            warn!("Could not set env vars for console id {}", msg.console_id);
+        }
+    }
+}
+
+pub fn plugin(app: &mut App) {
+    app.add_console_command::<SetCmd>();
+    app.add_systems(PreUpdate, on_msg);
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::test_harness;
+    use q_test_harness::prelude::*;
+    #[test]
+    fn test_set_cmd() {
+        let mut app = App::new();
+        app.add_plugins(test_harness::plugin);
+        let console_id = app.world_mut().spawn(Console).id();
+
+        app.add_step(
+            0,
+            move |mut commands: Commands, mut step: ResMut<NextState<Step>>| {
+                commands.write_message(CommandMsg::<SetCmd> {
+                    console_id,
+                    command: SetCmd {
+                        var: "foo".into(),
+                        val: "bar".into(),
+                    },
+                });
+                step.set(Step(1));
+            },
+        );
+
+        app.add_step(
+            1,
+            move |mut commands: Commands,
+                  q: Query<&ConsoleAssetHandle<ConsoleEnvVars>>,
+                  assets: Res<Assets<ConsoleEnvVars>>| {
+                let ok = (|| {
+                    let handle = q.get(console_id).ok()?;
+                    let vars = assets.get(handle.id())?;
+                    let ok = vars.get(&"foo".to_string()) == Some(&"bar".to_string());
+                    ok.then_some(true)
+                })();
+                if ok.unwrap_or_default() {
+                    commands.write_message(AppExit::Success);
+                } else {
+                    commands.write_message(AppExit::error());
+                }
+            },
+        );
+
+        assert!(app.run().is_success());
+    }
+}