diff --git a/prometheus_grafana_loki/readme.md b/prometheus_grafana_loki/readme.md
index a9cccef..5ae90c2 100644
--- a/prometheus_grafana_loki/readme.md
+++ b/prometheus_grafana_loki/readme.md
@@ -335,6 +335,7 @@ Links
 
 * [Stackoverflow - Prometheus instant vector vs range vector](https://stackoverflow.com/questions/68223824/prometheus-instant-vector-vs-range-vector)
 * [The Anatomy of a PromQL Query](https://promlabs.com/blog/2020/06/18/the-anatomy-of-a-promql-query/)
+* [Why are Prometheus queries hard?](https://fiberplane.com/blog/why-are-prometheus-queries-hard)
 * [Prometheus Cheat Sheet - Basics \(Metrics, Labels, Time Series, Scraping\)](https://iximiuz.com/en/posts/prometheus-metrics-labels-time-series/)
 * [Learning Prometheus and PromQL - Learning Series](https://iximiuz.com/en/series/learning-prometheus-and-promql/)
 * [The official](https://prometheus.io/docs/prometheus/latest/querying/basics/)