diff --git a/doc/d-utils.md b/doc/d-utils.md
index c187ea9..8a6cc2e 100644
--- a/doc/d-utils.md
+++ b/doc/d-utils.md
@@ -124,3 +124,62 @@ Returns a dictionary with the following keys:
 Returns annotated source with information about originating commits
 for each line.
 
+
+## util-io [module]
+
+    (import util-io)
+
+Module implementing advanced I/O.
+
+### read-lines/no-bom [procedure]
+
+    (read-lines/no-bom ip)
+
+
+* ```port``` - an input port
+
+Reads lines using ```read-lines``` and if the first line contains
+UTF-8 BOM, removes it.
+
+
+### get-process-output-lines [procedure]
+
+    (get-process-output-lines cmd
+                              . args)
+
+
+* ```cmd``` - a string with the command
+* ```args``` - list of arguments to pass to process
+
+Returns a list of strings representing all the lines produced by
+running the command given.
+
+
+### get-process-exit+output-lines [procedure]
+
+    (get-process-exit+output-lines cmd
+                                   . args)
+
+
+* ```cmd``` - a string with the command
+* ```args``` - list of arguments to pass to process
+
+Returns two values - an exit code and a list of strings representing
+all the lines produced by running the command given.
+
+
+### process-send/recv [procedure]
+
+    (process-send/recv cmd
+                       args
+                       . lines)
+
+
+* ```cmd``` - a string with command
+* ```args``` - list of arguments
+* ```lines``` - lines to feed to stdin of the process
+
+Executes given command ```cmd``` with given argument list ```args```
+writing all ```lines``` to its standard input and then reads all the
+process output.
+
diff --git a/doc/utils.md b/doc/utils.md
index 1fbf891..3c461a1 100644
--- a/doc/utils.md
+++ b/doc/utils.md
@@ -139,45 +139,6 @@ Converts given number to a string with two-digit fractional
 part. Should the fractional part be 0, it is replaced with the string
 "--".
 
-### IO
-
-    (import util-io)
-
-Module implementing advanced I/O.
-
-    (read-lines/no-bom port)
-
-* ```port``` - an input port
-
-Reads lines using ```read-lines``` and if the first line contains
-UTF-8 BOM, removes it.
-
-    (get-process-output-lines cmd . args)
-
-* ```cmd``` - a string with the command
-* ```args``` - list of arguments to pass to process
-
-Returns a list of strings representing all the lines produced by
-running the command given.
-
-    (get-process-exit+output-lines cmd . args)
-
-* ```cmd``` - a string with the command
-* ```args``` - list of arguments to pass to process
-
-Returns two values - an exit code and a list of strings representing
-all the lines produced by running the command given.
-
-    (process-send/recv cmd args . lines)
-
-* ```cmd``` - a string with command
-* ```args``` - list of arguments
-* ```lines``` - lines to feed to stdin of the process
-
-Executes given command ```cmd``` with given argument list ```args```
-writing all ```lines``` to its standard input and then reads all the
-process output.
-
 ### List
 
     (import util-list)
diff --git a/src/Makefile b/src/Makefile
index b23cf8d..76fd2f2 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -59,10 +59,11 @@ HACKERBASE-OBJS=hackerbase.o testing.o listing.o cal-month.o		\
 	 export-web-static.o util-dir.o dokuwiki.o racket-kwargs.o
 
 GENDOC-SOURCES=gendoc.scm duck-extract.import.scm			\
-	util-time.import.scm util-csv.import.scm util-git.import.scm
+	util-time.import.scm util-csv.import.scm util-git.import.scm	\
+	util-io.import.scm
 
 GENDOC-OBJS=gendoc.o duck-extract.o util-time.o util-csv.o util-io.o	\
-	progress.o testing.o util-proc.o util-git.o
+	progress.o testing.o util-proc.o util-git.o util-io.o
 
 .PHONY: imports
 imports: $(HACKERBASE-DEPS)
@@ -285,7 +286,7 @@ UTIL-TAG-SOURCES=util-tag.scm testing.import.scm
 util-tag.o: util-tag.import.scm
 util-tag.import.scm: $(UTIL-TAG-SOURCES)
 
-UTIL-IO-SOURCES=util-io.scm
+UTIL-IO-SOURCES=util-io.scm duck.import.scm
 
 util-io.o: util-io.import.scm
 util-io.import.scm: $(UTIL-IO-SOURCES)
diff --git a/src/gendoc.scm b/src/gendoc.scm
index fdd8a3e..b51ed77 100644
--- a/src/gendoc.scm
+++ b/src/gendoc.scm
@@ -22,4 +22,5 @@
 	  "These are various utility modules for other HackerBase libraries."
 	  util-time
 	  util-csv
-	  util-git)
+	  util-git
+	  util-io)
diff --git a/src/util-io.scm b/src/util-io.scm
index 2f44643..64c3b0e 100644
--- a/src/util-io.scm
+++ b/src/util-io.scm
@@ -25,8 +25,11 @@
 
 (declare (unit util-io))
 
-(module
+(import duck)
+
+(module*
  util-io
+ #:doc ("Module implementing advanced I/O.")
  (
   read-lines/no-bom
   get-process-output-lines
@@ -51,7 +54,13 @@
 
  ;; Reads lines from given input port, discarding BOM at the beginning
  ;; of the first line if there is any.
- (define (read-lines/no-bom ip)
+ (define/doc (read-lines/no-bom ip)
+   ("
+* ```port``` - an input port
+
+Reads lines using ```read-lines``` and if the first line contains
+UTF-8 BOM, removes it.
+")
    (let ((lines (read-lines ip)))
      (if (null? lines)
 	 lines
@@ -60,7 +69,14 @@
 
  ;; Very simple shell command wrapper that returns lines produced by
  ;; given command.
- (define (get-process-output-lines cmd . args)
+ (define/doc (get-process-output-lines cmd . args)
+   ("
+* ```cmd``` - a string with the command
+* ```args``` - list of arguments to pass to process
+
+Returns a list of strings representing all the lines produced by
+running the command given.
+")
    (let-values (((stdout stdin pid stderr)
 		 (process* cmd
 			   (map (lambda (x)
@@ -73,7 +89,14 @@
 
  ;; Very simple shell command wrapper that returns lines produced by
  ;; given command.
- (define (get-process-exit+output-lines cmd . args)
+ (define/doc (get-process-exit+output-lines cmd . args)
+   ("
+* ```cmd``` - a string with the command
+* ```args``` - list of arguments to pass to process
+
+Returns two values - an exit code and a list of strings representing
+all the lines produced by running the command given.
+")
    (let-values (((stdout stdin pid stderr)
 		 (process* cmd
 			   (map (lambda (x)
@@ -86,7 +109,16 @@
 
  ;; Invokes given command with given arguments, gives it all input
  ;; lines and returns the output lines.
- (define (process-send/recv cmd args . lines)
+ (define/doc (process-send/recv cmd args . lines)
+   ("
+* ```cmd``` - a string with command
+* ```args``` - list of arguments
+* ```lines``` - lines to feed to stdin of the process
+
+Executes given command ```cmd``` with given argument list ```args```
+writing all ```lines``` to its standard input and then reads all the
+process output.
+")
    (let-values (((stdout stdin pid stderr) (process* cmd args)))
      (let loop ((lines lines))
        (when (not (null? lines))