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README.md

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 # `histo`
 
-[![Build Status](https://travis-ci.org/fitzgen/histo.png?branch=master)](https://travis-ci.org/fitzgen/histo) [![histo on crates.io](https://img.shields.io/crates/v/histo.svg)](https://crates.io/crates/histo) [![histo on docs.rs](https://docs.rs/histo/badge.svg)](https://docs.rs/histo/)
+[![Rust](https://github.com/fitzgen/histo/actions/workflows/rust.yml/badge.svg)](https://github.com/fitzgen/histo/actions/workflows/rust.yml) [![histo on crates.io](https://img.shields.io/crates/v/histo.svg)](https://crates.io/crates/histo) [![histo on docs.rs](https://docs.rs/histo/badge.svg)](https://docs.rs/histo/)
 
 Histograms with a configurable number of buckets, and a terminal-friendly
 `Display`.