diff --git a/svg-flatten/include/gerbolyze.hpp b/svg-flatten/include/gerbolyze.hpp
index 7c54337..2fb7605 100644
--- a/svg-flatten/include/gerbolyze.hpp
+++ b/svg-flatten/include/gerbolyze.hpp
@@ -355,7 +355,9 @@ namespace gerbolyze {
         virtual ~SimpleSVGOutput() {}
         virtual SimpleSVGOutput &operator<<(const Polygon &poly);
         virtual SimpleSVGOutput &operator<<(GerberPolarityToken pol);
+        virtual SimpleSVGOutput &operator<<(const ApertureToken &ap);
         virtual SimpleSVGOutput &operator<<(const FlashToken &tok);
+        virtual bool can_do_apertures() { return true; }
         virtual void header_impl(d2p origin, d2p size);
         virtual void footer_impl();
 
@@ -364,6 +366,7 @@ namespace gerbolyze {
         std::string m_dark_color;
         std::string m_clear_color;
         std::string m_current_color;
+        double m_stroke_width;
         d2p m_offset;
     };
 
diff --git a/svg-flatten/src/out_svg.cpp b/svg-flatten/src/out_svg.cpp
index 80a5bdd..5ec061c 100644
--- a/svg-flatten/src/out_svg.cpp
+++ b/svg-flatten/src/out_svg.cpp
@@ -32,7 +32,8 @@ SimpleSVGOutput::SimpleSVGOutput(ostream &out, bool only_polys, int digits_frac,
     m_digits_frac(digits_frac),
     m_dark_color(dark_color),
     m_clear_color(clear_color),
-    m_current_color(dark_color)
+    m_current_color(dark_color),
+    m_stroke_width(std::nan("0"))
 {
 }
 
@@ -57,21 +58,36 @@ SimpleSVGOutput &SimpleSVGOutput::operator<<(GerberPolarityToken pol) {
     return *this;
 }
 
+SimpleSVGOutput &SimpleSVGOutput::operator<<(const ApertureToken &ap) {
+    m_stroke_width = ap.m_has_aperture ? ap.m_size : std::nan("0");
+    return *this;
+}
+
 SimpleSVGOutput &SimpleSVGOutput::operator<<(const Polygon &poly) {
     //cerr << "svg: got poly of size " << poly.size() << endl;
-    if (poly.size() < 3) {
-        cerr << "Warning: " << poly.size() << "-element polygon passed to SimpleGerberOutput" << endl;
+    if (std::isnan(m_stroke_width) && poly.size() < 3) {
+        cerr << "Warning: " << poly.size() << "-element polygon passed to SimpleSVGOutput in fill mode" << endl;
         return *this;
     }
 
-    m_out << "<path fill=\"" << m_current_color << "\" d=\"";
+    if (std::isnan(m_stroke_width)) {
+        m_out << "<path fill=\"" << m_current_color << "\" d=\"";
+    } else {
+        m_out << "<path stroke=\"" << m_current_color << "\" stroke-width=\"" << m_stroke_width << "\" stroke-linejoin=\"round\" stroke-linecap=\"round\" d=\"";
+    }
+
     m_out << "M " << setprecision(m_digits_frac) << (poly[0][0] + m_offset[0])
           << " " << setprecision(m_digits_frac) << (poly[0][1] + m_offset[1]);
+
     for (size_t i=1; i<poly.size(); i++) {
         m_out << " L " << setprecision(m_digits_frac) << (poly[i][0] + m_offset[0])
               << " " << setprecision(m_digits_frac) << (poly[i][1] + m_offset[1]);
     }
-    m_out << " Z";
+
+    if (std::isnan(m_stroke_width)) {
+        m_out << " Z";
+    }
+
     m_out << "\"/>" << endl;
 
     return *this;
diff --git a/svg-flatten/testdata/svg/xform_uniformity_threshold.svg b/svg-flatten/testdata/svg/xform_uniformity_threshold.svg
index 4198241..90fb3c8 100644
--- a/svg-flatten/testdata/svg/xform_uniformity_threshold.svg
+++ b/svg-flatten/testdata/svg/xform_uniformity_threshold.svg
@@ -3,8 +3,8 @@
 
 <svg
    width="80mm"
-   height="160mm"
-   viewBox="0 0 80 160"
+   height="100mm"
+   viewBox="0 0 80 100"
    version="1.1"
    id="svg5"
    inkscape:version="1.2.2 (b0a8486541, 2022-12-01)"
@@ -25,7 +25,7 @@
      inkscape:document-units="mm"
      showgrid="false"
      inkscape:zoom="1.5760525"
-     inkscape:cx="161.79664"
+     inkscape:cx="162.74839"
      inkscape:cy="175.75557"
      inkscape:window-width="1920"
      inkscape:window-height="1011"
@@ -39,7 +39,7 @@
        x="31.361818"
        y="59.900364"
        width="249.94496"
-       height="98.71728"
+       height="98.717278"
        id="rect256" />
   </defs>
   <g