diff --git a/build.zig.zon b/build.zig.zon
index 3f1b09f..983ac74 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -13,8 +13,8 @@
             .hash = "websocket-0.1.10-ZPISdUowBQAXIl_X9VpZozIxBLVf_o5wYjOMMdobrXF5",
         },
         .zio = .{
-            .url = "https://tangled.org/zzstoatzz.io/zio/archive/385c825.tar.gz",
-            .hash = "zio-0.0.0-psl_OY50AgAwn7tuMS37El_wwvypd_c4IVq2AninAAFj",
+            .url = "https://tangled.org/zzstoatzz.io/zio/archive/880de37.tar.gz",
+            .hash = "zio-0.0.0-psl_OZ58AgBSlB6fxXZfwqRFlPcvrOGTeASVE7e2hVh5",
         },
         .pg = .{
             .url = "https://tangled.org/zzstoatzz.io/pg.zig/archive/c5a5607.tar.gz",
diff --git a/src/main.zig b/src/main.zig
index 32d9f83..34bf5aa 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -187,6 +187,8 @@ const MetricsServer = struct {
                     \\zio_dns_spill{{kind="queued"}} {d}
                     \\zio_dns_spill{{kind="workers"}} {d}
                     \\zio_dns_spill{{kind="idle"}} {d}
+                    \\# HELP zio_fiber_starts live fibers by the function they run (leak finder)
+                    \\# TYPE zio_fiber_starts gauge
                     \\
                 , .{
                     d.sched.switches,       d.sched.live,          d.sched.ready,
@@ -194,11 +196,20 @@ const MetricsServer = struct {
                     d.sched.inject_pending, d.sched.free_list,     d.poller_registrations,
                     d.dns_queued,           d.dns_workers,         d.dns_idle,
                 }) catch "";
-                if (base_body.len + extra.len <= metrics_buf.len) {
-                    @memcpy(metrics_buf[base_body.len..][0..extra.len], extra);
-                    break :blk metrics_buf[0 .. base_body.len + extra.len];
+                var total = base_body.len;
+                if (total + extra.len <= metrics_buf.len) {
+                    @memcpy(metrics_buf[total..][0..extra.len], extra);
+                    total += extra.len;
                 }
-                break :blk base_body;
+                var starts_buf: [512]u8 = undefined;
+                for (d.starts) |sc| {
+                    if (sc.fn_addr == 0) continue;
+                    const line = std.fmt.bufPrint(&starts_buf, "zio_fiber_starts{{fn=\"0x{x}\"}} {d}\n", .{ sc.fn_addr, sc.count }) catch continue;
+                    if (total + line.len > metrics_buf.len) break;
+                    @memcpy(metrics_buf[total..][0..line.len], line);
+                    total += line.len;
+                }
+                break :blk metrics_buf[0..total];
             } else base_body;
 
             request.respond(body, .{ .status = .ok, .keep_alive = false, .extra_headers = &.{