diff --git a/README.md b/README.md
index 005a918..58c1a00 100644
--- a/README.md
+++ b/README.md
@@ -112,6 +112,10 @@ $ nix run nixpkgs#termsnap -- --columns 80 --lines 36 -- ls --color=always -l
 $ nix run nixpkgs#termsnap -- --interactive --out ./interactive-bash.svg -- bash
 ```
 
+The above takes Termsnap from the nixpkgs repository. To use the most up to
+date version on this repository's main branch, substitute `nixpkgs#termsnap` by
+`github:tomcur/termsnap`.
+
 ## A note on fonts
 
 The SVG generated by Termsnap makes assumptions about the metrics of the font
diff --git a/termsnap-lib/src/lib.rs b/termsnap-lib/src/lib.rs
index c6f6bf0..9c8c370 100644
--- a/termsnap-lib/src/lib.rs
+++ b/termsnap-lib/src/lib.rs
@@ -2,7 +2,7 @@
 //! SVG files.
 //!
 //! ```rust
-//! use termsnap_lib::{Term, VoidPtyWriter};
+//! use termsnap_lib::{FontMetrics, Term, VoidPtyWriter};
 //!
 //! // Create a new terminal emulator and process some bytes.
 //! let mut term = Term::new(24, 80, VoidPtyWriter);
@@ -20,7 +20,7 @@
 //! assert_eq!(&format!("{}", screen.get(0, 10).unwrap().fg), "#859900");
 //!
 //! // Render the screen to SVG.
-//! println!("{}", screen.to_svg(&[]));
+//! println!("{}", screen.to_svg(&[], FontMetrics::DEFAULT));
 //! ```
 
 #![forbid(unsafe_code)]
@@ -67,11 +67,13 @@ impl FontMetrics {
     /// or Menlo. If this is not accurate, it will be noticeable as overlap or gaps between box
     /// drawing characters.
     ///
-    /// ```
-    /// units_per_em: 1000
-    /// advance: 600.0
-    /// line_height: 1200.0
-    /// descent: 300.0
+    /// ```norun
+    /// FontMetrics {
+    ///     units_per_em: 1000,
+    ///     advance: 600.0,
+    ///     line_height: 1200.0,
+    ///     descent: 300.0,
+    /// }
     /// ```
     pub const DEFAULT: FontMetrics = FontMetrics {
         units_per_em: 1000,