{"ast_node_type":"variable","tokens":[{"end":78,"kind":"keyword","start":0,"text":"let"}]}
        let perf_revision = "a584462e145a0c04760fd9391daefb4f6bd13a99".into();
        let revision = cmd!(sh, "git rev-parse HEAD").read()?;
        Ok(Metrics { host, timestamp, revision, perf_revision, metrics: BTreeMap::new() })