diff --git a/src/config.ts b/src/config.ts
index f6489639883fe201eb3abbd16e198d3bfcfb0ac8..c401e7c3643cac1864501d685efa7b18528646f9 100644
--- a/src/config.ts
+++ b/src/config.ts
@@ -15,6 +15,9 @@ const Conf = {
   get publishRelays(): string[] {
     return deduplicate([Conf.nostrRelay, ...parseRelays(Deno.env.get('RELAY_PUBLISHERS'))]);
   },
+  get nip42key(): string | undefined {
+    return Deno.env.get('NIP42_KEY');
+  },
   get poolRelays(): string[] {
     return parseRelays(Deno.env.get('RELAY_POOL'));
   },
diff --git a/src/deps.ts b/src/deps.ts
index 4298c0ccd174e52176719326fd7c686aff9148a7..5b708d04ca3e469e16a83b42be328397922d978c 100644
--- a/src/deps.ts
+++ b/src/deps.ts
@@ -19,7 +19,16 @@ export {
   type HTMLDocument,
   type Node,
 } from 'https://deno.land/x/deno_dom@v0.1.45/deno-dom-native.ts';
-export { type Filter, getEventHash, matchFilter, nip19, nip21, nip27, validateEvent } from 'npm:nostr-tools@^2.3.1';
+export {
+  type Filter,
+  getEventHash,
+  matchFilter,
+  nip19,
+  nip21,
+  nip27,
+  nip42,
+  validateEvent,
+} from 'npm:nostr-tools@^2.3.1';
 export { finalizeEvent, generateSecretKey, getPublicKey, verifyEvent } from 'npm:nostr-tools@^2.3.1/wasm';
 export { z } from 'https://deno.land/x/zod@v3.22.4/mod.ts';
 export { default as linkify } from 'npm:linkifyjs@^4.1.3';
diff --git a/src/nostr/relay.ts b/src/nostr/relay.ts
index c3cfa8ce1477555426d9815af2631f448eed3dc7..1255f29369f35a9e8cf4f75f148ad24f88e88fca 100644
--- a/src/nostr/relay.ts
+++ b/src/nostr/relay.ts
@@ -1,7 +1,9 @@
 import { Conf } from '@/config.ts';
-import { RelayPool } from '@/deps.ts';
+import { nip42, RelayPool } from '@/deps.ts';
+import { finalizeEvent } from '@/deps.ts';
 
 import { nostrDate } from '../utils/parse.ts';
+import { decodeString } from 'https://deno.land/std@0.99.0/encoding/hex.ts';
 
 import handleEvent from './handler.ts';
 
@@ -10,6 +12,16 @@ const pool = new RelayPool(Conf.publishRelays, {
   skipVerification: true,
 });
 
+if (Conf.nip42key) {
+  pool.onauth((relay: any, challenge: string) => {
+    console.debug('NIP42 AUTH', relay.url);
+    const auth = nip42.makeAuthEvent(relay.url, challenge);
+    const signed_event = finalizeEvent(auth, decodeString(Conf.nip42key!));
+    relay.auth(signed_event);
+    // TODO: wait for OK reply or error
+  });
+}
+
 pool.subscribe(
   [{ kinds: [0, 1, 3, 5, 6, 7, 9735], since: nostrDate() }],
   Conf.publishRelays,