How to understand stack trace from SwiftUI crash

I'm building a WatchOS standalone app and submitting the build to Testflight via Xcode. When a user using a Apple Watch Series 3 downloads and installs the app, it immediately crashes on launch. I'm not sure what the stack trace is trying to tell me.

I've already tried running this on an Xcode Simulator, it does not crash. I've also tried uploading a blank app to TestFlight: it installs and launches on series 3. So there's something up with my own code.

Here's the stack trace I'm trying to understand...

NopeIncident Identifier: D924845A-DA02-43FD-9765-0F15BE819899
Beta Identifier:     88C0BC78-6216-4227-89E4-8665CA343785
Hardware Model:      Watch3,2
Process:             Nope WatchKit Extension [848]
Path:                /private/var/containers/Bundle/Application/...
Identifier:          com.nope.Nope.App.watchkitapp.watchkitextension
Version:             31 (1.0.0)
AppVariant:          1:Watch3,2:6
Beta:                YES
Code Type:           ARM (Native)
Role:                Foreground
Parent Process:      launchd [1]
Coalition:           com.nope.Nope.App.watchkitapp.watchkitextension [599]


Date/Time:           2019-09-04 18:04:42.1890 -0700
Launch Time:         2019-09-04 18:04:24.0000 -0700
OS Version:          Watch OS 6.0 (17R5575a)
Release Type:        User
Baseband Version:    4.00.00
Report Version:      104

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note:  EXC_CORPSE_NOTIFY
Triggered by Thread:  0

Application Specific Information:
abort() called

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libsystem_kernel.dylib          0x1b032fc8 0x1b016000 + 118728
1   libsystem_pthread.dylib         0x1b0aa3e2 0x1b0a6000 + 17378
2   libsystem_c.dylib               0x1afbc3a4 0x1af62000 + 369572
3   libswiftCore.dylib              0x357c23da 0x35589000 + 2331610
4   libswiftCore.dylib              0x357cf8ea 0x35589000 + 2386154
5   libswiftCore.dylib              0x357ce50e 0x35589000 + 2381070
6   SwiftUI                         0x1dab61de 0x1d9ed000 + 823774
7   SwiftUI                         0x1daaa1fa 0x1d9ed000 + 774650
8   SwiftUI                         0x1daa36fe 0x1d9ed000 + 747262
9   Nope WatchKit Extension         0x000f236c 0xec000 + 25452
10  SwiftUI                         0x1db06c36 0x1d9ed000 + 1154102
11  SwiftUI                         0x1db06cd4 0x1d9ed000 + 1154260
12  SwiftUI                         0x1da8d39e 0x1d9ed000 + 656286
13  SwiftUI                         0x1da8d314 0x1d9ed000 + 656148
14  SwiftUI                         0x1da8d3f0 0x1d9ed000 + 656368
15  SwiftUI                         0x1db0172e 0x1d9ed000 + 1132334
16  SwiftUI                         0x1db0c512 0x1d9ed000 + 1176850
17  SwiftUI                         0x1db06c36 0x1d9ed000 + 1154102
18  SwiftUI                         0x1db06cd4 0x1d9ed000 + 1154260
19  SwiftUI                         0x1daf9320 0x1d9ed000 + 1098528
20  SwiftUI                         0x1db0d8f4 0x1d9ed000 + 1181940
21  SwiftUI                         0x1db0172e 0x1d9ed000 + 1132334
22  SwiftUI                         0x1db0c512 0x1d9ed000 + 1176850
23  SwiftUI                         0x1de631ca 0x1d9ed000 + 4678090
24  SwiftUI                         0x1de63a12 0x1d9ed000 + 4680210
25  SwiftUI                         0x1de636e4 0x1d9ed000 + 4679396
26  SwiftUI                         0x1de65ffc 0x1d9ed000 + 4689916
27  AttributeGraph                  0x1e026c5e 0x1e024000 + 11358
28  AttributeGraph                  0x1e026e7c 0x1e024000 + 11900
29  AttributeGraph                  0x1e02a5f8 0x1e024000 + 26104
30  SwiftUI                         0x1db8187c 0x1d9ed000 + 1656956
31  SwiftUI                         0x1db81bb4 0x1d9ed000 + 1657780
32  SwiftUI                         0x1db81944 0x1d9ed000 + 1657156
33  SwiftUI                         0x1dd52464 0x1d9ed000 + 3560548
34  SwiftUI                         0x1dd5224a 0x1d9ed000 + 3560010
35  SwiftUI                         0x1dd4faa8 0x1d9ed000 + 3549864
36  SwiftUI                         0x1dedc524 0x1d9ed000 + 5174564
37  SwiftUI                         0x1dedc54a 0x1d9ed000 + 5174602
38  UIKitCore                       0x327e7acc 0x31c7f000 + 11963084
39  QuartzCore                      0x1f8e7ea8 0x1f7ca000 + 1171112
40  QuartzCore                      0x1f8eba26 0x1f7ca000 + 1186342
41  QuartzCore                      0x1f8f6752 0x1f7ca000 + 1230674
42  QuartzCore                      0x1f86260e 0x1f7ca000 + 624142
43  QuartzCore                      0x1f883c6a 0x1f7ca000 + 760938
44  UIKitCore                       0x32453c58 0x31c7f000 + 8211544
45  CoreFoundation                  0x1b3609b2 0x1b2da000 + 551346
46  CoreFoundation                  0x1b360398 0x1b2da000 + 549784
47  CoreFoundation                  0x1b35c4fa 0x1b2da000 + 533754
48  CoreFoundation                  0x1b35be8a 0x1b2da000 + 532106
49  GraphicsServices                0x1e12ecd0 0x1e12c000 + 11472
50  UIKitCore                       0x3244047a 0x31c7f000 + 8131706
51  libxpc.dylib                    0x1b0f7dc0 0x1b0da000 + 122304
52  libxpc.dylib                    0x1b0e8c04 0x1b0da000 + 60420
53  libxpc.dylib                    0x1b0eab04 0x1b0da000 + 68356
54  Foundation                      0x1bbd8046 0x1bb9c000 + 245830
55  PlugInKit                       0x22c9c684 0x22c8a000 + 75396
56  WatchKit                        0x2a448720 0x2a37c000 + 837408
57  libdyld.dylib                   0x1af11e52 0x1af0e000 + 15954

Thread 1:
0   libsystem_pthread.dylib         0x1b0b00e8 0x1b0a6000 + 41192

Thread 2:
0   libsystem_pthread.dylib         0x1b0b00e8 0x1b0a6000 + 41192

Thread 3 name:  com.apple.uikit.eventfetch-thread
Thread 3:
0   libsystem_kernel.dylib          0x1b01b7f4 0x1b016000 + 22516
1   libsystem_kernel.dylib          0x1b01aeae 0x1b016000 + 20142
2   CoreFoundation                  0x1b360596 0x1b2da000 + 550294
3   CoreFoundation                  0x1b35c62e 0x1b2da000 + 534062
4   CoreFoundation                  0x1b35be8a 0x1b2da000 + 532106
5   Foundation                      0x1bba4150 0x1bb9c000 + 33104
6   Foundation                      0x1bba406c 0x1bb9c000 + 32876
7   UIKitCore                       0x324bc802 0x31c7f000 + 8640514
8   Foundation                      0x1bca6300 0x1bb9c000 + 1090304
9   libsystem_pthread.dylib         0x1b0a9548 0x1b0a6000 + 13640
10  libsystem_pthread.dylib         0x1b0b0114 0x1b0a6000 + 41236

Thread 4 name:  Dispatch queue: com.apple.root.utility-qos
Thread 4:
0   SwiftUI                         0x1dae2644 0x1d9ed000 + 1005124
1   libswiftCore.dylib              0x357dafea 0x35589000 + 2433002
2   libswiftCore.dylib              0x357dba3a 0x35589000 + 2435642
3   libswiftCore.dylib              0x357db8c2 0x35589000 + 2435266
4   AttributeGraph                  0x1e02bfb4 0x1e024000 + 32692
5   AttributeGraph                  0x1e02d21e 0x1e024000 + 37406
6   libdispatch.dylib               0x1aed6448 0x1aed2000 + 17480
7   libdispatch.dylib               0x1aee2b18 0x1aed2000 + 68376
8   libdispatch.dylib               0x1aee2f66 0x1aed2000 + 69478
9   libsystem_pthread.dylib         0x1b0aafa4 0x1b0a6000 + 20388
10  libsystem_pthread.dylib         0x1b0b00fc 0x1b0a6000 + 41212

Thread 0 crashed with ARM Thread State (32-bit):
    r0: 0x00000000    r1: 0x00000000      r2: 0x00000000      r3: 0x00000000
    r4: 0x00000006    r5: 0x00000507      r6: 0x0026f460      r7: 0x0026f3a8
    r8: 0x003ed8f0    r9: 0x00000000     r10: 0x0026f410     r11: 0x00000020
    ip: 0x00000148    sp: 0x0026f390      lr: 0x1b0aa3e3      pc: 0x1b032fc8
  cpsr: 0x40000010

....

Error Formulating Crash Report:
thread_get_state(...ARM_EXCEPTION_STATE64) returned 4: (os/kern) invalid argument

EOF

I suspect it's something with SwiftUI, but is there any way to tell what's going on?