diff --git a/schema/index.yaml b/schema/index.yaml
index 2dcb917..32b4921 100644
--- a/schema/index.yaml
+++ b/schema/index.yaml
@@ -75,6 +75,8 @@ $defs:
           "^[\\w]+":
             type: string
             format: uri
+      speakers:
+        type: array
   person:
     type: object
     additionalProperties: false
diff --git a/src/events/index.yaml b/src/events/index.yaml
index ec7abbc..da66219 100644
--- a/src/events/index.yaml
+++ b/src/events/index.yaml
@@ -13,6 +13,26 @@
   links:
     web: https://prague.web3privacy.info/
     git: https://github.com/web3privacy/w3ps1
+  speakers:
+    - ameen-soleimani
+    - guy-zyskind
+    - max-hampshire
+    - antoni-zolciak
+    - rachel-rose-oleary
+    - alex-kampa
+    - oliver-gale
+    - mario-havel
+    - costanza-gallo 
+    - manu-alzuru
+    - nick-almond
+    - juraj-bednar
+    - dcbuilder
+    - alona-shevchenko
+    - tibor-csoka
+    - merula
+    - serinko
+    - steffen-kux
+    - althea
 
 - id: w3ps2
   type: summit
diff --git a/src/index.yaml b/src/index.yaml
index 100bec2..3be9a8b 100644
--- a/src/index.yaml
+++ b/src/index.yaml
@@ -18,9 +18,11 @@ core-team:
   - name: Coinmandeer
 projects:
   $load: projects
-events:
-  $load: events
 people:
   $load: people
   $opts:
-    loader: person
\ No newline at end of file
+    loader: person
+events:
+  $load: events
+  $opts:
+    loader: events
\ No newline at end of file
diff --git a/utils/engine.js b/utils/engine.js
index 1d5432a..e4dcbab 100644
--- a/utils/engine.js
+++ b/utils/engine.js
@@ -26,13 +26,25 @@ export class Engine {
     this.rendered = await this.render(this.index);
   }
 
-  async loadDir(src, opts = {}) {
+  async loadDir(src, opts = {}, full = {}) {
     const out = {};
     const dir = join(SRC_DIR, src);
     console.log(`reading dir=${dir}`);
 
     if (await exists(join(dir, "index.yaml"))) {
-      const out = readYamlFile(join(dir, "index.yaml"));
+      const out = await readYamlFile(join(dir, "index.yaml"));
+      if (opts.loader === "events") {
+        // check speaker connection
+        for (const ev of out) {
+          if (ev.speakers) {
+            for (const spId of ev.speakers) {
+              if (!full.people.find((p) => p.id === spId)) {
+                throw new Error(`Speaker not exists: ${spId} (event ${ev.id})`);
+              }
+            }
+          }
+        }
+      }
       return out;
     }
 
@@ -50,7 +62,7 @@ export class Engine {
       if (!ext && !fn.startsWith("_")) {
         const obj = Object.assign(
           { id: fn },
-          await this.loadDir(join(src, fn)),
+          await this.loadDir(join(src, fn), opts, full),
         );
         arr.push(obj);
       }
@@ -78,7 +90,7 @@ export class Engine {
     for (const key of Object.keys(src)) {
       const val = src[key];
       if (typeof val === "object" && val.$load) {
-        out[key] = await this.loadDir(val.$load, val.$opts);
+        out[key] = await this.loadDir(val.$load, val.$opts, out);
         continue;
       }