diff --git a/default-recommendations/comment-preservation-test.rkt b/default-recommendations/comment-preservation-test.rkt
new file mode 100644
index 00000000..c692eb15
--- /dev/null
+++ b/default-recommendations/comment-preservation-test.rkt
@@ -0,0 +1,104 @@
+#lang resyntax/test
+
+
+require: resyntax/default-recommendations let-replacement
+
+
+header:
+- #lang racket/base
+
+
+test: "expression comments are preserved between let bindings"
+------------------------------
+(define (foo)
+  (let ([x 1]
+        #;(debug-binding [z 0])
+        [y 2])
+    (+ x y)))
+==============================
+(define (foo)
+  (define x 1)
+  #;(debug-binding [z 0])
+  (define y 2)
+  (+ x y))
+------------------------------
+
+
+test: "expression comments with atoms are preserved between let bindings"
+------------------------------
+(define (foo)
+  (let ([x 1]
+        #;unused-binding
+        [y 2])
+    (+ x y)))
+==============================
+(define (foo)
+  (define x 1)
+  #;unused-binding
+  (define y 2)
+  (+ x y))
+------------------------------
+
+
+test: "block comments are preserved between let bindings"
+------------------------------
+(define (foo)
+  (let ([x 1]
+        #| The second
+           binding |#
+        [y 2])
+    (+ x y)))
+==============================
+(define (foo)
+  (define x 1)
+  #| The second
+           binding |#
+  (define y 2)
+  (+ x y))
+------------------------------
+
+
+test: "expression comments with nested sexps are preserved"
+------------------------------
+(define (foo)
+  (let ([x 1]
+        #;(commented-binding
+           [y 3]
+           [z 4])
+        [a 2])
+    (+ x a)))
+==============================
+(define (foo)
+  (define x 1)
+  #;(commented-binding [y 3] [z 4])
+  (define a 2)
+  (+ x a))
+------------------------------
+
+
+test: "expression comments in let body are preserved"
+------------------------------
+(define (foo)
+  (let ([x 1])
+    #;(debug-stmt)
+    (+ x 1)))
+==============================
+(define (foo)
+  (define x 1)
+  #;(debug-stmt)
+  (+ x 1))
+------------------------------
+
+
+test: "block comments in let body are preserved"
+------------------------------
+(define (foo)
+  (let ([x 1])
+    #| computation |#
+    (+ x 1)))
+==============================
+(define (foo)
+  (define x 1)
+  #| computation |#
+  (+ x 1))
+------------------------------
diff --git a/main.rkt b/main.rkt
index bcf381b1..a9db4ebb 100644
--- a/main.rkt
+++ b/main.rkt
@@ -54,7 +54,6 @@
          resyntax/base
          resyntax/default-recommendations
          resyntax/private/analysis
-         resyntax/private/comment-reader
          resyntax/private/git
          resyntax/private/limiting
          resyntax/private/line-replacement
@@ -170,7 +169,7 @@
                                 #:suite [suite default-recommendations]
                                 #:lines [lines (range-set (unbounded-range #:comparator natural<=>))]
                                 #:timeout-ms [timeout-ms 10000])
-  (define comments (with-input-from-source source read-comment-locations))
+  (define comments (source-comment-locations source))
   (define source-lang (source-read-language source))
   (guard source-lang #:else
     (log-resyntax-warning "skipping ~a because its #lang could not be determined"
@@ -235,7 +234,7 @@
 (define/guard (reysntax-analyze-for-properties-only source
                                                     #:suite [suite default-recommendations]
                                                     #:timeout-ms [timeout-ms 10000])
-  (define comments (with-input-from-source source read-comment-locations))
+  (define comments (source-comment-locations source))
   (define full-source (source->string source))
   (guard (string-prefix? full-source "#lang racket") #:else
     (log-resyntax-warning "skipping ~a because it does not start with #lang racket"
diff --git a/private/comment-reader.rkt b/private/comment-reader.rkt
deleted file mode 100644
index 49b7f95a..00000000
--- a/private/comment-reader.rkt
+++ /dev/null
@@ -1,129 +0,0 @@
-#lang racket/base
-
-
-(require racket/contract/base)
-
-
-(provide
- (contract-out
-  [read-comment-locations (->* () (input-port?) range-set?)]))
-
-
-(require br-parser-tools/lex
-         racket/sequence
-         rebellion/base/comparator
-         rebellion/base/range
-         rebellion/collection/list
-         rebellion/collection/range-set
-         rebellion/streaming/reducer
-         rebellion/streaming/transducer
-         resyntax/private/syntax-traversal
-         (prefix-in : br-parser-tools/lex-sre))
-
-
-(module+ test
-  (require rackunit
-           (submod "..")))
-
-
-;@----------------------------------------------------------------------------------------------------
-
-
-(define (read-comment-locations [in (current-input-port)])
-  (port-count-lines! in)
-  (define (next!)
-    (comment-lexer in))
-  (transduce (in-producer next! eof)
-             (mapping srcloc-token-srcloc)
-             (mapping srcloc-range)
-             #:into (into-range-set natural<=>)))
-
-
-(define (srcloc-range srcloc)
-  (define start (sub1 (srcloc-position srcloc)))
-  (define end (+ start (srcloc-span srcloc)))
-  (closed-open-range start end #:comparator natural<=>))
-
-
-(define-tokens racket-tokens (LINE-COMMENT BLOCK-COMMENT))
-
-
-(define-lex-abbrev racket-line-comment
-  (concatenation ";" (complement (:: any-string "\n" any-string)) "\n"))
-
-
-(define (build-racket-line-comment lexeme)
-  (token-LINE-COMMENT (string->immutable-string lexeme)))
-
-
-;; Technically not correct because block comments can be nested.
-(define-lex-abbrev racket-block-comment
-  (concatenation "#|" (complement (:: any-string (:or "#|" "#|") any-string)) "|#"))
-
-
-(define (build-racket-block-comment lexeme)
-  (token-BLOCK-COMMENT (string->immutable-string lexeme)))
-
-
-;; This lexer should also read string literals and discard them, so that comment-starting characters
-;; inside string literals are ignored.
-(define comment-lexer
-  (lexer-srcloc
-   [racket-line-comment (build-racket-line-comment lexeme)]
-   [racket-block-comment (build-racket-block-comment lexeme)]
-   [any-char (return-without-srcloc (comment-lexer input-port))]))
-
-
-(module+ test
-  (test-case "comment-lexer"
-
-    (define (natural-range start end)
-      (closed-open-range start end #:comparator natural<=>))
-
-    (define (read-comments-for-test test-program)
-      (read-comment-locations (open-input-string test-program 'test-program)))
-
-    (test-case "line comments"
-      (define input "; This is a comment\n")
-      (define expected (range-set (natural-range 0 20)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "double semicolon line comments"
-      (define input ";; This is a comment\n")
-      (define expected (range-set (natural-range 0 21)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "line comments after expressions"
-      (define input "(void) ; This is a comment\n")
-      (define expected (range-set (natural-range 7 27)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "line comments above expressions"
-      (define input "; This is a comment\n(void)\n")
-      (define expected (range-set (natural-range 0 20)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "line comments with non-ASCII characters"
-      (define input "; λλλλλ\n")
-      (define expected (range-set (natural-range 0 8)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "block comments"
-      (define input "#|\nThis is a block comment\n|#\n")
-      (define expected (range-set (natural-range 0 29)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "block comments below expressions"
-      (define input "(void)\n#|\nThis is a block comment\n|#\n")
-      (define expected (range-set (natural-range 7 36)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "block comments above expressions"
-      (define input "#|\nThis is a block comment\n|#\n(void)\n")
-      (define expected (range-set (natural-range 0 29)))
-      (check-equal? (read-comments-for-test input) expected))
-
-    (test-case "multiple line comments"
-      (define input "; Line 1\n; Line 2\n; Line 3\n")
-      (define expected (range-set (natural-range 0 27)))
-      (check-equal? (read-comments-for-test input) expected))))
diff --git a/private/source.rkt b/private/source.rkt
index 1f7ddd47..b68c4907 100644
--- a/private/source.rkt
+++ b/private/source.rkt
@@ -18,6 +18,7 @@
   [source-expand (-> source? syntax?)]
   [source-can-expand? (-> source? boolean?)]
   [source-text-of (-> source? syntax? immutable-string?)]
+  [source-comment-locations (-> source? immutable-range-set?)]
   [file-source? (-> any/c boolean?)]
   [file-source (-> path-string? file-source?)]
   [file-source-path (-> file-source? path?)]
@@ -38,7 +39,13 @@
          rebellion/base/immutable-string
          resyntax/private/syntax-neighbors
          syntax/modread
-         syntax/parse)
+         rebellion/base/comparator
+         rebellion/base/range
+         rebellion/collection/range-set
+         rebellion/collection/vector/builder
+         rebellion/streaming/transducer
+         syntax-color/lexer-contract
+         syntax-color/module-lexer)
 
 
 (module+ test
@@ -179,3 +186,45 @@
   (define start (sub1 (syntax-position stx)))
   (define end (+ start (syntax-span stx)))
   (string->immutable-string (substring (source->string code) start end)))
+
+
+(define (source-comment-locations src)
+  (transduce (source-tokens src)
+             (filtering lexical-token-comment?)
+             (mapping lexical-token-location)
+             #:into (into-range-set natural<=>)))
+
+
+(struct lexical-token (text start end type delimiter-kind attributes) #:transparent)
+
+
+(define (source-tokens src)
+  (with-input-from-source src
+    (λ ()
+      (define tokens (make-vector-builder))
+      (let loop ([offset 0] [mode #false])
+        (define-values (text raw-attributes delimiter-kind start end _ new-mode)
+          (module-lexer* (current-input-port) offset mode))
+        (unless (eof-object? text)
+          (define type
+            (if (symbol? raw-attributes)
+                raw-attributes
+                (hash-ref raw-attributes 'type)))
+          (define attributes
+            (if (symbol? raw-attributes)
+                (hasheq)
+                (hash-remove raw-attributes 'type)))
+          (vector-builder-add tokens (lexical-token text (sub1 start) (sub1 end) type delimiter-kind attributes))
+          (loop (sub1 end) (if (dont-stop? new-mode) (dont-stop-val new-mode) new-mode))))
+      (build-vector tokens))))
+
+
+(define (lexical-token-comment? token)
+  (define type (lexical-token-type token))
+  (or (equal? type 'comment)
+      (equal? type 'sexp-comment)
+      (hash-ref (lexical-token-attributes token) 'comment? #false)))
+
+
+(define (lexical-token-location token)
+  (closed-open-range (lexical-token-start token) (lexical-token-end token) #:comparator natural<=>))
diff --git a/test/private/rackunit.rkt b/test/private/rackunit.rkt
index 17a9f096..424d4f49 100644
--- a/test/private/rackunit.rkt
+++ b/test/private/rackunit.rkt
@@ -128,7 +128,7 @@
 
 (define current-line-mask (make-parameter (range-set (unbounded-range #:comparator natural<=>))))
 
-(define current-analyzer-timeout-millis (make-parameter 100))
+(define current-analyzer-timeout-millis (make-parameter 1000))
 
 
 (define (range-bound-add bound amount)