diff -ur a/include/gemmi/json.hpp b/include/gemmi/json.hpp
--- a/include/gemmi/json.hpp
+++ b/include/gemmi/json.hpp
@@ -38,6 +38,7 @@
 
 inline std::string as_cif_value(const sajson::value& val) {
   switch (val.get_type()) {
+    case sajson::TYPE_INTEGER:
     case sajson::TYPE_DOUBLE:
       return val.as_string();
     case sajson::TYPE_NULL:
le id='header'>
<tr>
<td class='logo' rowspan='2'><a href='/'><img src='https://git.koszko.org/cgit-static/cgit.png' alt='cgit logo'/></a></td>
<td class='main'><a href='/'>index</a> : <a href='/guix/'>guix</a></td><td class='form'><form method='get'>
<input type='hidden' name='id' value='71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'/><select name='h' onchange='this.form.submit();'>
<option value='koszko' selected='selected'>koszko</option>
<option value='koszko-scripts'>koszko-scripts</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>Wojtek's customized Guix</td><td class='sub right'></td></tr></table>
<table class='tabs'><tr><td>
<a href='/guix/about/'>about</a><a href='/guix/'>summary</a><a href='/guix/refs/?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>refs</a><a class='active' href='/guix/log/gnu/packages/scanner.scm'>log</a><a href='/guix/tree/gnu/packages/scanner.scm?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>tree</a><a href='/guix/commit/gnu/packages/scanner.scm?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>commit</a><a href='/guix/diff/gnu/packages/scanner.scm?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/packages/scanner.scm'>
<input type='hidden' name='id' value='71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>root</a>/<a href='/guix/log/gnu?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>gnu</a>/<a href='/guix/log/gnu/packages?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>packages</a>/<a href='/guix/log/gnu/packages/scanner.scm?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f'>scanner.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/scanner.scm?id=71e1d0a4373f6cc5cd99e1400fb87d64d97c370f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-08-18 02:00:00 +0200'>2024-08-18</span></td><td><a href='/guix/commit/gnu/packages/scanner.scm?id=c65098345739ccaccb293a5d7976fecc6b3d7beb'>gnu: xsane: Fix cross-compilation.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2024-08-18 02:00:00 +0200'>2024-08-18</span></td><td><a href='/guix/commit/gnu/packages/scanner.scm?id=e12c377ed15ab99a8830e3437aa560d411ec3202'>gnu: xsane: Update package style.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2024-06-24 08:51:37 -0400'>2024-06-24</span></td><td><a href='/guix/commit/gnu/packages/scanner.scm?id=7d0a6d3e740b77b1fe58e71970eb0cea91afbc29'>gnu: sane-backends: Update to 1.3.1.</a><span class='msg-avail'>...</span></td><td>Andy Tai</td></tr>
<tr><td><span title='2024-02-16 13:40:19 +0100'>2024-02-16</span></td><td><a href='/guix/commit/gnu/packages/scanner.scm?id=8fee233246c75aff0a1daa420604d7c60ae434f5'>gnu: sane-backends-minimal: Update to 1.2.1.</a><span class='msg-avail'>...</span></td><td>John Fremlin</td></tr>