1 files changed, 45 insertions, 0 deletions

diff --git a/src/bitflashd.cpp b/src/bitflashd.cpp
new file mode 100644
index 0000000..d4ced77
--- /dev/null
+++ b/src/bitflashd.cpp
@@ -0,0 +1,45 @@
+// Copyright (c) 2026 Bitflash developers
+// Distributed under the MIT/X11 software license.
+//
+// bitflashd -- the headless Bitflash rendezvous relay (the "meeting node").
+// Runs on a machine with a public IP (a cheap VPS) and lets nodes behind CGNAT
+// reach each other: both sides connect OUT to this relay, which pairs them by
+// `.btf` pubkey and forwards ciphertext (it holds no keys and reads nothing).
+//
+// Build on the VPS (Linux):
+//   g++ -std=gnu++14 -O2 -pthread bitflashd.cpp btfrv.cpp -o bitflashd
+// Run:
+//   ./bitflashd 8434        # or any port you open in the firewall
+//
+// Cross-builds unchanged on Windows (for local testing):
+//   g++ -std=gnu++14 -O2 -pthread bitflashd.cpp btfrv.cpp -lws2_32 -o bitflashd.exe
+
+#include "btfrv.h"
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+int main(int argc, char* argv[])
+{
+    unsigned short port = 8434;
+    if (argc >= 2)
+        port = (unsigned short)atoi(argv[1]);
+
+    printf("bitflashd -- Bitflash rendezvous relay\n");
+    printf("listening on 0.0.0.0:%u (open this port in your firewall)\n", port);
+    fflush(stdout);
+
+    if (!btf::RvInit())
+    {
+        fprintf(stderr, "bitflashd: socket init failed\n");
+        return 1;
+    }
+
+    // Blocks forever, forwarding between paired peers.
+    if (!btf::RvRelayRun(port))
+    {
+        fprintf(stderr, "bitflashd: could not bind/listen on port %u\n", port);
+        return 1;
+    }
+    return 0;
+}