diff --git a/crates/fbuild-config/src/board/types.rs b/crates/fbuild-config/src/board/types.rs
index 8ff560a8..fdaf416a 100644
--- a/crates/fbuild-config/src/board/types.rs
+++ b/crates/fbuild-config/src/board/types.rs
@@ -30,7 +30,11 @@ pub(super) const EMULATOR_TOOL_NAMES: &[&str] =
     &["simavr", "qemu", "renode", "ovpsim", "verilator"];
 
 /// Board configuration loaded from boards.txt or built-in defaults.
-#[derive(Debug, Clone, Serialize, Deserialize)]
+///
+/// `Default` exists for struct-update test construction
+/// (`BoardConfig { mcu: ..., ..Default::default() }`); a defaulted
+/// config is not a usable board definition.
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
 pub struct BoardConfig {
     pub name: String,
     pub mcu: String,
diff --git a/crates/fbuild-deploy/src/probe_rs.rs b/crates/fbuild-deploy/src/probe_rs.rs
index 46b63a43..481cb675 100644
--- a/crates/fbuild-deploy/src/probe_rs.rs
+++ b/crates/fbuild-deploy/src/probe_rs.rs
@@ -1,7 +1,7 @@
 //! probe-rs SWD flash path (FastLED/fbuild#935, #936).
 //!
 //! The FastLED fork of `probe-rs` — sources maintained on the `tools`
-//! branch of [`FastLED/framework-arduino-lpc8xx`], cross-compiled by
+//! branch of `FastLED/framework-arduino-lpc8xx`, cross-compiled by
 //! `.github/workflows/fastled-release-cross.yml` — carries three
 //! patches on top of upstream that together allow it to talk to the
 //! LPC-Link2 v1.0.7 CMSIS-DAP firmware that ships on the LPC845-BRK: