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README.md

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-[Grafana](https://grafana.com) [![Circle CI](https://circleci.com/gh/grafana/grafana.svg?style=svg)](https://circleci.com/gh/grafana/grafana)
+[Grafana](https://grafana.com) [![Circle CI](https://circleci.com/gh/grafana/grafana.svg?style=svg)](https://circleci.com/gh/grafana/grafana) [![Go Report Card](https://goreportcard.com/badge/github.com/grafana/grafana)](https://goreportcard.com/report/github.com/grafana/grafana)
 ================
 [Website](https://grafana.com) |
 [Twitter](https://twitter.com/grafana) |