sit crashes after requesting user info

gistfile1.txt

export RUST_BACKTRACE=1 ; target/debug/sit web                  
SIT needs your authorship identity to be configured

What is your name? fix
What is your e-mail address? fix@deeprecursion.com
thread 'main' panicked at 'can't open config file for writing: Os { code: 2, kind: NotFound, message: "No such file or directory" }', libcore/result.rs:1009:5
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::print
             at libstd/sys_common/backtrace.rs:71
             at libstd/sys_common/backtrace.rs:59
   2: std::panicking::default_hook::{{closure}}
             at libstd/panicking.rs:211
   3: std::panicking::default_hook
             at libstd/panicking.rs:227
   4: <std::panicking::begin_panic::PanicPayload<A> as core::panic::BoxMeUp>::get
             at libstd/panicking.rs:477
   5: std::panicking::continue_panic_fmt
             at libstd/panicking.rs:391
   6: std::panicking::try::do_call
             at libstd/panicking.rs:326
   7: core::ptr::drop_in_place
             at libcore/panicking.rs:77
   8: core::ptr::swap_nonoverlapping_bytes
             at /private/tmp/rust-20181109-36555-1v9zmop/rustc-1.30.1-src/src/libcore/macros.rs:26
   9: <core::result::Result<T, E>>::expect
             at /private/tmp/rust-20181109-36555-1v9zmop/rustc-1.30.1-src/src/libcore/result.rs:835
  10: sit::authorship::derive_authorship
             at sit/src/authorship.rs:37
  11: sit::command_web::command
             at sit/src/command_web.rs:10
  12: sit::main_with_result::do_matches
             at sit/src/main.rs:576
  13: sit::main_with_result
             at sit/src/main.rs:498
  14: sit::main
             at sit/src/main.rs:128
  15: std::rt::lang_start::{{closure}}
             at /private/tmp/rust-20181109-36555-1v9zmop/rustc-1.30.1-src/src/libstd/rt.rs:74
  16: std::panicking::try::do_call
             at libstd/rt.rs:59
             at libstd/panicking.rs:310
  17: macho_symbol_search
             at libpanic_unwind/lib.rs:103
  18: std::sys_common::bytestring::debug_fmt_bytestring
             at libstd/panicking.rs:289
             at libstd/panic.rs:392
             at libstd/rt.rs:58
  19: std::rt::lang_start
             at /private/tmp/rust-20181109-36555-1v9zmop/rustc-1.30.1-src/src/libstd/rt.rs:74
  20: sit::main_with_result