Java Flight Recorder (JFR) captures an enormous amount of detail about what your application is doing — but raw JFR files are only as useful as the tools you have to explore them. Jeffrey is an open-source JFR analyzer that specializes in turning JFR events into interactive visualizations, and Jeffrey Microscope is its standalone, single-user deployment: a self-contained application that lets you import recordings and dig into flamegraphs, timeseries, and other views right in your browser. Getting started takes a minute: Standalone JAR – download the latest microscope.jar from the GitHub releases page and start it with java -jar microscope.jar (Java 25 or newer). Docker – skip the setup entirely with docker run -it --network host petrbouda/microscope. Sample recordings – if you want to explore the tool before profiling your own application, the petrbouda/microscope-examples image ships with sample recordings preloaded (docker run -it --network host petrbouda/microscope-examples).In this article, we'll use Jeffrey Microscope to analyze JFR flamegraphs and walk through how they help you find where your application actually spends its time.