diff --git a/src/amduatd.c b/src/amduatd.c
index be61cd5..86639bb 100644
--- a/src/amduatd.c
+++ b/src/amduatd.c
@@ -224,14 +224,18 @@ static const char k_amduatd_ui_html[] =
     "        </div>\n"
     "        <div class=\"row\" style=\"margin-top:10px;\">\n"
     "          <select id=\"mode\">\n"
-    "            <option value=\"text\">text (utf-8)</option>\n"
-    "            <option value=\"base64\">base64</option>\n"
-    "            <option value=\"hex\">hex</option>\n"
+    "            <option value=\"text\">bytes: text (utf-8)</option>\n"
+    "            <option value=\"base64\">bytes: base64</option>\n"
+    "            <option value=\"hex\">bytes: hex</option>\n"
+    "            <option value=\"pel_program\">PEL program: JSON</option>\n"
     "          </select>\n"
-    "          <input id=\"typeTag\" placeholder=\"X-Amduat-Type-Tag (optional, e.g. 0x00000101)\" />\n"
+    "          <input id=\"typeTag\" placeholder=\"X-Amduat-Type-Tag (optional)\" />\n"
     "          <input id=\"latestRef\" placeholder=\"latest_ref\" readonly />\n"
     "        </div>\n"
-    "        <textarea id=\"editor\" spellcheck=\"false\" placeholder=\"(concept bytes)\"></textarea>\n"
+    "        <textarea id=\"editor\" spellcheck=\"false\" placeholder=\"(bytes or PEL program authoring JSON)\"></textarea>\n"
+    "        <div class=\"row\" style=\"margin-top:10px;\">\n"
+    "          <button class=\"btn\" id=\"btnProgramTemplate\" type=\"button\">Insert identity program</button>\n"
+    "        </div>\n"
     "        <div class=\"row\" style=\"margin-top:10px;\">\n"
     "          <input id=\"publishRef\" placeholder=\"publish existing ref\" />\n"
     "          <button class=\"btn\" id=\"btnPublishRef\" type=\"button\">Publish ref</button>\n"
@@ -289,12 +293,22 @@ static const char k_amduatd_ui_html[] =
     "      el('latestRef').value = j.latest_ref || '';\n"
     "      el('programRef').value = name;\n"
     "      if(!j.latest_ref){ el('editor').value=''; out(text); return; }\n"
+    "      const mode = el('mode').value;\n"
     "      const infoResp = await fetch(`/v1/artifacts/${j.latest_ref}?format=info`);\n"
     "      if(infoResp.ok){ const info = JSON.parse(await infoResp.text()); el('typeTag').value = info.has_type_tag ? info.type_tag : ''; }\n"
+    "      if(mode === 'pel_program'){\n"
+    "        if(!el('editor').value.trim()){\n"
+    "          el('editor').value = JSON.stringify({\n"
+    "            nodes:[{id:1,op:{name:'pel.bytes.concat',version:1},inputs:[{external:{input_index:0}}],params_hex:''}],\n"
+    "            roots:[{node_id:1,output_index:0}]\n"
+    "          }, null, 2);\n"
+    "        }\n"
+    "        out(text);\n"
+    "        return;\n"
+    "      }\n"
     "      const aResp = await fetch(`/v1/artifacts/${j.latest_ref}`);\n"
     "      if(!aResp.ok){ out(await aResp.text()); return; }\n"
     "      const u8 = new Uint8Array(await aResp.arrayBuffer());\n"
-    "      const mode = el('mode').value;\n"
     "      if(mode==='hex') el('editor').value = toHex(u8);\n"
     "      else if(mode==='base64') el('editor').value = toB64(u8);\n"
     "      else el('editor').value = td.decode(u8);\n"
@@ -306,6 +320,19 @@ static const char k_amduatd_ui_html[] =
     "      if(!name){ out('missing concept name'); return; }\n"
     "      await ensureConcept(name);\n"
     "      const mode = el('mode').value;\n"
+    "      if(mode === 'pel_program'){\n"
+    "        const body = JSON.parse(el('editor').value || '{}');\n"
+    "        const mkResp = await fetch('/v1/pel/programs',{method:'POST',headers:{'Content-Type':'application/json'},body:JSON.stringify(body)});\n"
+    "        const mkText = await mkResp.text();\n"
+    "        if(!mkResp.ok){ out(mkText); return; }\n"
+    "        const mk = JSON.parse(mkText);\n"
+    "        const pref = mk.program_ref;\n"
+    "        const pubResp = await fetch(`/v1/concepts/${encodeURIComponent(name)}/publish`,{method:'POST',headers:{'Content-Type':'application/json'},body:JSON.stringify({ref:pref})});\n"
+    "        const pubText = await pubResp.text();\n"
+    "        out(pubText);\n"
+    "        if(pubResp.ok){ el('typeTag').value = '0x00000101'; await loadConcept(); }\n"
+    "        return;\n"
+    "      }\n"
     "      let u8;\n"
     "      if(mode==='hex') u8 = fromHex(el('editor').value);\n"
     "      else if(mode==='base64') u8 = fromB64(el('editor').value);\n"
@@ -326,7 +353,21 @@ static const char k_amduatd_ui_html[] =
     "    el('btnConceptCreate').addEventListener('click', async () => { try{ await ensureConcept(el('conceptName').value.trim()); out('{\"ok\":true}\\n'); }catch(e){ out(String(e)); } });\n"
     "    el('btnLoad').addEventListener('click', () => loadConcept().catch(e => out(String(e))));\n"
     "    el('btnSave').addEventListener('click', () => saveConcept().catch(e => out(String(e))));\n"
-    "    el('mode').addEventListener('change', () => loadConcept().catch(() => {}));\n"
+    "    el('mode').addEventListener('change', () => {\n"
+    "      if(el('mode').value === 'pel_program'){\n"
+    "        el('typeTag').value = '0x00000101';\n"
+    "      }\n"
+    "      loadConcept().catch(() => {});\n"
+    "    });\n"
+    "\n"
+    "    el('btnProgramTemplate').addEventListener('click', () => {\n"
+    "      el('mode').value = 'pel_program';\n"
+    "      el('typeTag').value = '0x00000101';\n"
+    "      el('editor').value = JSON.stringify({\n"
+    "        nodes:[{id:1,op:{name:'pel.bytes.concat',version:1},inputs:[{external:{input_index:0}}],params_hex:''}],\n"
+    "        roots:[{node_id:1,output_index:0}]\n"
+    "      }, null, 2);\n"
+    "    });\n"
     "\n"
     "    el('btnPublishRef').addEventListener('click', async () => {\n"
     "      try{\n"