title: Actix web example from introduction gives run-time error thread 'main' panicked at 'called `Option::unwrap()` on a `None` value'
body: <p>I am starting to use actix-web using the example from the getting started section of the actix web guide. When running the code I get a runtime error that appears to come from the actix framework.</p>
  
  <p>Versions:</p>
  
  <ul>
  <li>win10</li>
  <li>rustc 1.33.0 (2aa4c46cf 2019-02-28)</li>
  <li>actix-web 0.7.18 </li>
  </ul>
  
  <p>This is the code:</p>
  
  <pre><code>extern crate actix_web;
  use std::env;
  use actix_web::{server, App, HttpRequest};
  
  fn index(_req: &amp;HttpRequest) -&gt; &amp;'static str {
      "Hello World!"
  }
  
  fn main() {
      env::set_var("RUST_BACKTRACE","1");
  
      server::new(
          || App::new()
              .resource("/", |r| r.f(index)))
          .bind("127.0.0.1:8088")
          .unwrap()
          .run();
  }
  </code></pre>
  
  <p>It compiles ok, but I get the following backtrace, relevant lines in the backtrace appear to be line 11 where the panic seems to occur and line 73, which shows the call in my main function that ultimately leads to the panic.</p>
  
  <p>I double checked that port 8088 is available. What am I doing wrong?</p>
  
  <pre><code>   Compiling hello_cargo v0.1.0 (D:\users\Jan Debeuckelaer\projects\hello_cargo)
      Finished dev [unoptimized + debuginfo] target(s) in 7.97s
       Running `target\debug\hello_cargo.exe`
  thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', src\libcore\option.rs:345:21
  stack backtrace:
     0: std::sys::windows::backtrace::set_frames
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\sys\windows\backtrace\mod.rs:94
     1: std::sys::windows::backtrace::unwind_backtrace
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\sys\windows\backtrace\mod.rs:81
     2: std::sys_common::backtrace::_print
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\sys_common\backtrace.rs:70
     3: std::sys_common::backtrace::print
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\sys_common\backtrace.rs:58
     4: std::panicking::default_hook::{{closure}}
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:200
     5: std::panicking::default_hook
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:215
     6: std::panicking::rust_panic_with_hook
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:478
     7: std::panicking::continue_panic_fmt
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:385
     8: std::panicking::rust_begin_panic
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:312
     9: core::panicking::panic_fmt
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libcore\panicking.rs:85
    10: core::panicking::panic
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libcore\panicking.rs:49
    11: core::option::Option&lt;(mio::poll::Registration, mio::poll::SetReadiness)*&gt;::unwrap&lt;(mio::poll::Registration, mio::poll::SetReadiness)*&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libcore\macros.rs:10
    12: tokio_signal::windows::global_init
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-signal-0.2.8\src\windows.rs:165
    13: tokio_signal::windows::{{impl}}::new::{{closure}}
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-signal-0.2.8\src\windows.rs:118
    14: std::sync::once::{{impl}}::call_once::{{closure}}&lt;closure&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\sync\once.rs:220
    15: std::sync::once::Once::call_inner
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\sync\once.rs:387
    16: std::sync::once::Once::call_once&lt;closure&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\sync\once.rs:220
    17: tokio_signal::windows::Event::new
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-signal-0.2.8\src\windows.rs:117
    18: tokio_signal::windows::Event::ctrl_c_handle
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-signal-0.2.8\src\windows.rs:96
    19: tokio_signal::ctrl_c_handle::ctrl_c_imp::{{closure}}
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-signal-0.2.8\src\lib.rs:137
    20: futures::future::lazy::Lazy&lt;closure, futures::future::map::Map&lt;alloc::boxed::Box&lt;Future&gt;, closure&gt;&gt;::get&lt;closure,futures::future::map::Map&lt;alloc::boxed::Box&lt;Future&gt;, closure&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\lazy.rs:64
    21: futures::future::lazy::{{impl}}::poll&lt;closure,futures::future::map::Map&lt;alloc::boxed::Box&lt;Future&gt;, closure&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\lazy.rs:82
    22: futures::future::{{impl}}::poll&lt;Future&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\mod.rs:113
    23: futures::future::map_err::{{impl}}::poll&lt;(),alloc::boxed::Box&lt;Future&gt;,closure&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\map_err.rs:30
    24: actix::fut::{{impl}}::poll&lt;futures::future::map_err::MapErr&lt;alloc::boxed::Box&lt;Future&gt;, closure&gt;,actix::actors::signal::ProcessSignals&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\fut\mod.rs:389
    25: actix::fut::map::{{impl}}::poll&lt;(),actix::fut::FutureWrap&lt;futures::future::map_err::MapErr&lt;alloc::boxed::Box&lt;Future&gt;, closure&gt;, actix::actors::signal::ProcessSignals&gt;,closure&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\fut\map.rs:38
    26: actix::fut::{{impl}}::poll&lt;ActorFuture&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\fut\mod.rs:313
    27: actix::contextimpl::{{impl}}::poll&lt;actix::actors::signal::ProcessSignals,actix::context::Context&lt;actix::actors::signal::ProcessSignals&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\contextimpl.rs:355
    28: actix::supervisor::{{impl}}::poll&lt;actix::actors::signal::ProcessSignals&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\supervisor.rs:147
    29: futures::future::{{impl}}::poll&lt;actix::supervisor::Supervisor&lt;actix::actors::signal::ProcessSignals&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\mod.rs:113
    30: futures::future::{{impl}}::poll&lt;Future&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\future\mod.rs:113
    31: futures::task_impl::{{impl}}::poll_future_notify::{{closure}}&lt;alloc::boxed::Box&lt;Future&gt;,tokio_current_thread::scheduler::Notify&lt;tokio_reactor::Handle&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\mod.rs:326
    32: futures::task_impl::{{impl}}::enter::{{closure}}&lt;alloc::boxed::Box&lt;Future&gt;,closure,core::result::Result&lt;futures::poll::Async&lt;()&gt;, ()&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\mod.rs:396
    33: futures::task_impl::std::set&lt;closure,core::result::Result&lt;futures::poll::Async&lt;()&gt;, ()&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\std\mod.rs:78
    34: futures::task_impl::Spawn&lt;alloc::boxed::Box&lt;Future&gt;&gt;::enter&lt;alloc::boxed::Box&lt;Future&gt;,closure,core::result::Result&lt;futures::poll::Async&lt;()&gt;, ()&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\mod.rs:396
    35: futures::task_impl::Spawn&lt;alloc::boxed::Box&lt;Future&gt;&gt;::poll_fn_notify&lt;alloc::boxed::Box&lt;Future&gt;,tokio_current_thread::scheduler::Notify&lt;tokio_reactor::Handle&gt;,closure,core::result::Result&lt;futures::poll::Async&lt;()&gt;, ()&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\mod.rs:288
    36: futures::task_impl::Spawn&lt;alloc::boxed::Box&lt;Future&gt;&gt;::poll_future_notify&lt;alloc::boxed::Box&lt;Future&gt;,tokio_current_thread::scheduler::Notify&lt;tokio_reactor::Handle&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\futures-0.1.25\src\task_impl\mod.rs:326
    37: tokio_current_thread::scheduler::Scheduled&lt;tokio_reactor::Handle&gt;::tick&lt;tokio_reactor::Handle&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\scheduler.rs:351
    38: tokio_current_thread::scheduler::{{impl}}::tick::{{closure}}&lt;tokio_reactor::Handle&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\scheduler.rs:330
    39: tokio_current_thread::{{impl}}::enter::{{closure}}::{{closure}}&lt;tokio_reactor::Handle,closure,bool&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:788
    40: tokio_current_thread::CurrentRunner::set_spawn&lt;closure,bool&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:825
    41: tokio_current_thread::{{impl}}::enter::{{closure}}&lt;tokio_reactor::Handle,closure,bool&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:788
    42: std::thread::local::LocalKey&lt;tokio_current_thread::CurrentRunner&gt;::try_with&lt;tokio_current_thread::CurrentRunner,closure,bool&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:299
    43: std::thread::local::LocalKey&lt;tokio_current_thread::CurrentRunner&gt;::with&lt;tokio_current_thread::CurrentRunner,closure,bool&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:245
    44: tokio_current_thread::Borrow&lt;tokio_reactor::Handle&gt;::enter&lt;tokio_reactor::Handle,closure,bool&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:786
    45: tokio_current_thread::scheduler::Scheduler&lt;tokio_reactor::Handle&gt;::tick&lt;tokio_reactor::Handle&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\scheduler.rs:330
    46: tokio_current_thread::Entered&lt;tokio_timer::timer::Timer&lt;tokio_reactor::Reactor, tokio_timer::clock::clock::Clock&gt;&gt;::tick&lt;tokio_timer::timer::Timer&lt;tokio_reactor::Reactor, tokio_timer::clock::clock::Clock&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:612
    47: tokio_current_thread::Entered&lt;tokio_timer::timer::Timer&lt;tokio_reactor::Reactor, tokio_timer::clock::clock::Clock&gt;&gt;::block_on&lt;tokio_timer::timer::Timer&lt;tokio_reactor::Reactor, tokio_timer::clock::clock::Clock&gt;,futures::sync::oneshot::Receiver&lt;i32&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-current-thread-0.1.6\src\lib.rs:502
    48: tokio::runtime::current_thread::runtime::{{impl}}::block_on::{{closure}}&lt;futures::sync::oneshot::Receiver&lt;i32&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:200
    49: tokio::runtime::current_thread::runtime::{{impl}}::enter::{{closure}}::{{closure}}::{{closure}}::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:241
    50: tokio_executor::global::with_default::{{closure}}&lt;tokio_current_thread::TaskExecutor,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-executor-0.1.7\src\global.rs:209
    51: std::thread::local::LocalKey&lt;core::cell::Cell&lt;tokio_executor::global::State&gt;&gt;::try_with&lt;core::cell::Cell&lt;tokio_executor::global::State&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:299
    52: std::thread::local::LocalKey&lt;core::cell::Cell&lt;tokio_executor::global::State&gt;&gt;::with&lt;core::cell::Cell&lt;tokio_executor::global::State&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:245
    53: tokio_executor::global::with_default&lt;tokio_current_thread::TaskExecutor,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-executor-0.1.7\src\global.rs:178
    54: tokio::runtime::current_thread::runtime::{{impl}}::enter::{{closure}}::{{closure}}::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:239
    55: tokio_timer::timer::handle::with_default::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-timer-0.2.10\src\timer\handle.rs:94
    56: std::thread::local::LocalKey&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_timer::timer::handle::HandlePriv&gt;&gt;&gt;::try_with&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_timer::timer::handle::HandlePriv&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:299
    57: std::thread::local::LocalKey&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_timer::timer::handle::HandlePriv&gt;&gt;&gt;::with&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_timer::timer::handle::HandlePriv&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:245
    58: tokio_timer::timer::handle::with_default&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-timer-0.2.10\src\timer\handle.rs:81
    59: tokio::runtime::current_thread::runtime::{{impl}}::enter::{{closure}}::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:232
    60: tokio_timer::clock::clock::with_default::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-timer-0.2.10\src\clock\clock.rs:141
    61: std::thread::local::LocalKey&lt;core::cell::Cell&lt;core::option::Option&lt;const tokio_timer::clock::clock::Clock*&gt;&gt;&gt;::try_with&lt;core::cell::Cell&lt;core::option::Option&lt;const tokio_timer::clock::clock::Clock*&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:299
    62: std::thread::local::LocalKey&lt;core::cell::Cell&lt;core::option::Option&lt;const tokio_timer::clock::clock::Clock*&gt;&gt;&gt;::with&lt;core::cell::Cell&lt;core::option::Option&lt;const tokio_timer::clock::clock::Clock*&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:245
    63: tokio_timer::clock::clock::with_default&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-timer-0.2.10\src\clock\clock.rs:124
    64: tokio::runtime::current_thread::runtime::{{impl}}::enter::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:231
    65: tokio_reactor::with_default::{{closure}}&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-reactor-0.1.9\src\lib.rs:237
    66: std::thread::local::LocalKey&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_reactor::HandlePriv&gt;&gt;&gt;::try_with&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_reactor::HandlePriv&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:299
    67: std::thread::local::LocalKey&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_reactor::HandlePriv&gt;&gt;&gt;::with&lt;core::cell::RefCell&lt;core::option::Option&lt;tokio_reactor::HandlePriv&gt;&gt;,closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\thread\local.rs:245
    68: tokio_reactor::with_default&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-reactor-0.1.9\src\lib.rs:217
    69: tokio::runtime::current_thread::runtime::Runtime::enter&lt;closure,core::result::Result&lt;i32, futures::sync::oneshot::Canceled&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:230
    70: tokio::runtime::current_thread::runtime::Runtime::block_on&lt;futures::sync::oneshot::Receiver&lt;i32&gt;&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\tokio-0.1.18\src\runtime\current_thread\runtime.rs:198
    71: actix::system::SystemRunner::run
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-0.7.9\src\system.rs:174
    72: actix_web::server::http::HttpServer&lt;actix_web::application::App&lt;()&gt;, closure&gt;::run&lt;actix_web::application::App&lt;()&gt;,closure&gt;
               at C:\Users\Jan Debeuckelaer\.cargo\registry\src\github.com-1ecc6299db9ec823\actix-web-0.7.18\src\server\http.rs:539
    73: hello_cargo::main
               at .\src\main.rs:12
    74: std::rt::lang_start::{{closure}}&lt;()&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\rt.rs:64
    75: std::rt::lang_start_internal::{{closure}}
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\rt.rs:49
    76: std::panicking::try::do_call&lt;closure,i32&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:297
    77: panic_unwind::__rust_maybe_catch_panic
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libpanic_unwind\lib.rs:92
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panicking.rs:276
    79: std::panic::catch_unwind
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\panic.rs:388
    80: std::rt::lang_start_internal
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\/src\libstd\rt.rs:48
    81: std::rt::lang_start&lt;()&gt;
               at /rustc/2aa4c46cfdd726e97360c2734835aa3515e8c858\src\libstd\rt.rs:64
    83: invoke_main
               at d:\agent\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78
    84: __scrt_common_main_seh
               at d:\agent\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288
    85: BaseThreadInitThunk
    86: RtlUserThreadStart
  Panic in Arbiter thread, shutting down system.
  </code></pre>