@@ -614,17 +614,47 @@
 			return htmlSpan(v.spans, b, s)
 		end
 
 		function span_renderers.link(sp,b,s)
+			local dest_o, _, dest_s = b.origin:ref(sp.ref)
 			local href
-			if b.origin.doc.sections[sp.ref] then
-				href = '#' .. getSafeID(sp)
+			if dest_o == nil then
+				-- link is to the section itself
+				href = '#' .. getSafeID(dest_s)
 			else
-				if sp.addr then href = sp.addr else
-					local r = b.origin:ref(sp.ref)
-					if type(r) == 'table' then
-						href = '#' .. getSafeID(r)
-					else href = r end
+-- 				if sp.addr then href = sp.addr else
+				if type(dest_o) == 'table' then
+					href = '#' .. getSafeID(dest_o)
+				else -- URI in reference
+					local uri = ss.uri(dest_o)
+					if uri.class[1] == 'file'
+					or uri.class[1] == 'asset' then
+						if uri.namespace == 'localhost' then
+							-- emit an actual file url
+							href = 'file://' .. uri:construct('path','frag')
+						elseif uri.namespace == nil then
+							-- this is gonna be tricky. first we establish the location
+							-- of the CWD/asset base relative to the output file (if any;
+							-- assume equivalent otherwise) then express the difference
+							-- as a directory prefix.
+							-- jk tho for now we just emit the path+frag sadlol TODO
+							href = uri:construct('path','frag')
+						else
+							b.origin:fail('file: URI namespace must be empty or “localhost” for HTML links; others are not meaningful (offending URI: “%s”)', dest_o)
+						end
+					elseif uri:canfetch() == 'http' then
+						local sc = 'http'
+						if uri.class[1] == 'https' or uri.class[2] == 'tls' then
+							sc = 'https'
+						end
+						if uri.namespace == nil and uri.auth == nil and uri.svc == nil then
+							-- omit the scheme so we can use a relative path
+							href = uri:construct('path','query','frag')
+						else
+							uri.class = {sc}
+							href = tostring(uri)
+						end
+					else href = tostring(uri) end
 				end
 			end
 			return tag('a',{href=href},next(sp.spans) and htmlSpan(sp.spans,b,s) or href)
 		end