diff --git a/core/core-editor.el b/core/core-editor.el
index 41d64ffe6..d1f9a78b7 100644
--- a/core/core-editor.el
+++ b/core/core-editor.el
@@ -426,11 +426,20 @@ files, so we replace calls to `pp' with the much faster `prin1'."
         undo-tree-history-directory-alist
         `(("." . ,(concat doom-cache-dir "undo-tree-hist/"))))
 
+  ;; Compress undo-tree history files with zstd, if available. File size isn't
+  ;; the (only) concern here: the file IO barrier is slow for Emacs to cross;
+  ;; reading a tiny file and piping it in-memory through zstd is *slightly*
+  ;; faster than Emacs reading the entire undo-tree file from the get go (on
+  ;; SSDs). Whether or not that's true in practice, we still enjoy zstd's ~80%
+  ;; file savings (these files add up over time and zstd is so incredibly fast).
   (when (executable-find "zstd")
     (defadvice! doom--undo-tree-make-history-save-file-name-a (file)
       :filter-return #'undo-tree-make-history-save-file-name
       (concat file ".zst")))
 
+  ;; Strip text properties from undo-tree data to stave off bloat. File size
+  ;; isn't the concern here; undo cache files bloat easily, which can cause
+  ;; freezing, crashes, GC-induced stuttering or delays when opening files.
   (defadvice! doom--undo-tree-strip-text-properties-a (&rest _)
     :before #'undo-list-transfer-to-tree
     (dolist (item buffer-undo-list)