diff --git a/Makefile b/Makefile
index bee2cda..ef82847 100644
--- a/Makefile
+++ b/Makefile
@@ -14,4 +14,7 @@ format:
 fmt: format
 
 build:
-	deno run --unstable --allow-read --allow-write utils/exec.js build
\ No newline at end of file
+	deno run --unstable --allow-read --allow-write utils/exec.js build
+
+event-sync:
+	deno run --unstable --allow-read --allow-write --allow-net utils/eventSync.js
diff --git a/data/23/events/utxo/_sync.js b/data/23/events/utxo/_sync.js
new file mode 100644
index 0000000..3c7012e
--- /dev/null
+++ b/data/23/events/utxo/_sync.js
@@ -0,0 +1,7 @@
+export async function data($) {
+  const bundle = await $.loadJSONUrl("https://spec.utxo.cz/23/bundle.json");
+  return {
+    speakers: bundle.spec.speakers,
+    tracks: bundle.spec.tracks,
+  };
+}
diff --git a/data/23/events/utxo/data.json b/data/23/events/utxo/data.json
new file mode 100644
index 0000000..3601fdd
--- /dev/null
+++ b/data/23/events/utxo/data.json
@@ -0,0 +1,110 @@
+{
+  "speakers": [
+    {
+      "id": "petr-lukac",
+      "name": "Petr Lukáč",
+      "twitter": "RuzovejSlon",
+      "bio": "Novinář, podcaster",
+      "orgs": "Podcast [Krypto Space](https://www.kryptospace.cz/)\n",
+      "tracks": [
+        "spolecnost"
+      ],
+      "country": "cz",
+      "photos": [
+        "web:png",
+        "twitter:jpg"
+      ]
+    },
+    {
+      "id": "tereza-starostova",
+      "name": "Tereza Starostová",
+      "twitter": "terkastarostova",
+      "orgs": "Spoluzakladatelka [Holky v Kryptu](https://holkyvkryptu.cz/), předsedkyně [UTXO Foundation](httsp://utxo.foundation)\n",
+      "tracks": [
+        "zaklady",
+        "spolecnost"
+      ],
+      "country": "cz",
+      "photos": [
+        "twitter:jpg"
+      ]
+    },
+    {
+      "id": "tree",
+      "name": "tree",
+      "twitter": "treecz",
+      "bio": "Libertarián, propagátor Web3 a DAOs",
+      "orgs": "Zakladatel [Gwei.cz](https://gwei.cz). Organizátor [ETHBrno](https://ethbrno.cz/), [UTXO.23](https://utxo.cz) a dalších akcí\n",
+      "country": "cz",
+      "tracks": [
+        "eth",
+        "defi",
+        "dao"
+      ],
+      "desc": "Founder of @gweicz | 🦄 #Ethereum #DeFi #DAO enthusiast 🦇🔊 | ✈️ #travel maniac | ⚡ riding #electricunicycle | 🇨🇿🇬🇧 lang | 🟡⚫ | 🇺🇦 Слава Україні!\n",
+      "photos": [
+        "twitter:jpg"
+      ]
+    }
+  ],
+  "tracks": [
+    {
+      "id": "zaklady",
+      "name": "Základy kryptoměn",
+      "shortname": "Základy",
+      "examples": "* principy otevřených projektů (blockchainů)\n* základy bezpečnosti a soukromí\n* peněženky - SW, HW\n* základy obchodování - DCA\n"
+    },
+    {
+      "id": "btc",
+      "name": "Bitcoin",
+      "examples": "* Bitcoin jako peníze\n* Lightning Network - adopce, implementace\n* Taproot\n* Bitcoin mining\n* smart-kontrakty na bitcoinu (RGB)\n"
+    },
+    {
+      "id": "eth",
+      "name": "Ethereum a smart-kontrakty obecně",
+      "shortname": "Ethereum",
+      "examples": "* Ethereum 2.0\n* Layer2 - rollupy\n* (EVM) Sidechainy\n* vývoj smart-kontraktů (solidity)\n* MEV - Miner Extractable Value\n"
+    },
+    {
+      "id": "defi",
+      "name": "Decentralizované finance (DeFi)",
+      "shortname": "DeFi",
+      "examples": "* stablecoiny\n* lending protokoly\n* DEX - decentralizované burzy\n* predikční trhy\n* futures/options kontrakty\n* tokenizace\n"
+    },
+    {
+      "id": "dao",
+      "name": "Decentralizované organizace (DAO)",
+      "shortname": "DAOs",
+      "examples": "* budoucnost organizací\n* showcase jednotlivých DAOs\n"
+    },
+    {
+      "id": "nft",
+      "name": "NFTs a Metaverse",
+      "shortname": "NFTs/Metaverse",
+      "examples": "* NFT umění\n* NFT collectibles\n* gaming\n* Metaverse\n"
+    },
+    {
+      "id": "alty",
+      "name": "Experimentální L1 blockchainy a další altcoiny",
+      "shortname": "Alternativní L1",
+      "examples": "* Polkadot\n* Cardano\n* Cosmos (Secret Network..)\n* Solana\n* NEAR\n* Monero\n* ...\n"
+    },
+    {
+      "id": "regulace",
+      "name": "Regulace a fiat rampy",
+      "shortname": "Regulace",
+      "examples": "* legislativa\n* směnárny a burzy\n* darování kryptoměn\n* insitucionální peníze v kryptoměnách\n"
+    },
+    {
+      "id": "spolecnost",
+      "name": "Krypto-společnost",
+      "shortname": "Společnost",
+      "examples": "* odluka peněz od státu\n* kryptoanarchismus, anarchokapitalismus, meritokracie\n* představení lokálních krypto-komunit\n* fenomén maximalismu\n"
+    },
+    {
+      "id": "other",
+      "name": "Ostatní",
+      "hidden": true
+    }
+  ]
+}
diff --git a/utils/engine.js b/utils/engine.js
index 4410452..4c84bc7 100644
--- a/utils/engine.js
+++ b/utils/engine.js
@@ -1,6 +1,7 @@
 import { emptyDir, exists } from "https://deno.land/std@0.119.0/fs/mod.ts";
 import { parse as tomlParse } from "https://deno.land/std@0.173.0/encoding/toml.ts";
 import { load as yamlLoad } from "https://deno.land/x/js_yaml_port@3.14.0/js-yaml.js";
+import * as syncTools from "./syncTools.js";
 
 let _silentMode = false;
 
@@ -13,7 +14,7 @@ export class DeConfEngine {
     this.githubUrl = this.options.githubUrl ||
       "https://github.com/utxo-foundation/prague-blockchain-week/tree/main/data";
 
-    if (options.silentMode) {
+    if (options.silent) {
       _silentMode = true;
     }
   }
@@ -108,18 +109,36 @@ class DeConf_Event {
   constructor(id) {
     this.id = id;
     this.data = null;
+    this.dir = null;
   }
 
   async load(dir) {
+    this.dir = dir.join("/");
     const efIndex = await _tomlLoad([...dir, "index.toml"].join("/"));
-    const event = {
+    const data = {
       index: { id: this.id, ...efIndex },
     };
-    this.data = event;
+    const syncDataFn = [...dir, "data.json"].join("/");
+    if (await exists(syncDataFn)) {
+      data.sync = await _jsonLoad(syncDataFn);
+    }
+    this.data = data;
+  }
+
+  async sync() {
+    const syncFile = [this.dir, "_sync.js"].join("/");
+    if (!await exists(syncFile)) return null;
+    if (!_silentMode) console.log(`syncing ${this.id} ..`);
+    const module = await import("../" + syncFile);
+    // data
+    if (module.data) {
+      const data = await module.data(syncTools);
+      await _jsonWrite([this.dir, "data.json"].join("/"), data);
+    }
   }
 
   toJSON() {
-    return Object.assign({ id: this.id }, this.data.index);
+    return Object.assign({ id: this.id }, this.data.index, this.data.sync);
   }
 }
 
@@ -139,3 +158,6 @@ async function _jsonWrite(fn, data) {
   }
   return true;
 }
+async function _jsonLoad(fn) {
+  return JSON.parse(await Deno.readTextFile(fn));
+}
diff --git a/utils/eventSync.js b/utils/eventSync.js
new file mode 100644
index 0000000..b4a510e
--- /dev/null
+++ b/utils/eventSync.js
@@ -0,0 +1,12 @@
+import { DeConfEngine } from "./engine.js";
+
+const dc = new DeConfEngine();
+await dc.init();
+
+// pick last entry (eq. "23")
+const entry = dc.entries[dc.entries.length - 1];
+console.log(`entry=${entry.id}`);
+
+for (const event of entry.data.events) {
+  await event.sync();
+}
diff --git a/utils/syncTools.js b/utils/syncTools.js
new file mode 100644
index 0000000..001828e
--- /dev/null
+++ b/utils/syncTools.js
@@ -0,0 +1,5 @@
+export async function loadJSONUrl(url) {
+  const resp = await fetch(url);
+  const data = await resp.json();
+  return data;
+}