self.project_roots = roots;

    async fn update_project_roots(&mut self) -> Result<()> {
        let roots = self.find_project_roots().await?;
        trace!(roots = ?roots);

        let to_remove: Vec<_> = self
            .roots
            .iter()
            .filter(|p| !self.roots.contains(*p))
            .cloned()
            .collect();

        let to_add: Vec<_> = roots
            .iter()
            .filter(|p| !self.project_roots.contains(*p))
            .cloned()
            .collect();

        for path in to_add.iter() {
            self.scan_project(path).await?;
        }

        match self.watcher.as_mut() {
            Some(watcher) => {
                for path in to_remove {
                    watcher.unwatch(path.join("out"))?;
                }
                for path in to_add {
                    watcher.watch(path.join("out"), RecursiveMode::Recursive)?;
                }
            }

            None => {
                warn!("forge watcher not initialized");
            }
        }

        Ok(())