diff --git a/README.md b/README.md
index 71d23d3..f4f0e0e 100644
--- a/README.md
+++ b/README.md
@@ -45,6 +45,16 @@ root = "~/documents/finances"
 A leading `~` is expanded and relative paths are made absolute. `money config`
 prints the resolved root and which of the four rules chose it.
 
+## Install
+
+```
+go install ./cmd/money
+```
+
+Give it the package path, not `cmd/money/main.go`. Naming the file puts the go
+tool in file mode: it names the binary after the source file (`main`) and
+compiles only the files listed, which breaks the moment the package has two.
+
 ## Usage
 
 ```