Convert Gemtext to HTML
Perl 5 (-p), 132 bytes

s,^((#)|(\*)|=&gt; (\S+)|) *(.*?) *$,$t=$2?h1:$3?li:$4?a:p;&quot;&lt;$t&quot;.($4&amp;&amp;qq( href=&quot;$4&quot;)).&quot;&gt;&quot;.($5=~s~[&lt;&gt;&quot;&amp;]~&quot;&amp;#&quot;.(ord$&amp;).&quot;;&quot;~ger).&quot;&lt;/$t&gt;&quot;,e

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Another 132 bytes
s-^([#*]|=&gt; (\S+)|) *(.*?) *$-&quot;&lt;&quot;.($t=(p,a,li,h1)[ord($1)%4]).($2&amp;&amp;qq( href=&quot;$2&quot;)).&quot;&gt;&quot;.($3=~s~[&lt;&gt;&quot;&amp;]~&quot;&amp;#&quot;.(ord$&amp;).&quot;;&quot;~ger).&quot;&lt;/$t&gt;&quot;-e