Here's the import crash:

0   ???                           	               0x0 ???
1   libpython3.13.dylib           	       0x103b950d8 state_fini + 228
2   libpython3.13.dylib           	       0x103b92828 _sre_SRE_Pattern_match + 712
3   libpython3.13.dylib           	       0x1038a3cd0 method_vectorcall_FASTCALL_KEYWORDS_METHOD + 188
4   libpython3.13.dylib           	       0x1038938c8 PyObject_VectorcallMethod + 168
5   libpython3.13.dylib           	       0x1039f242c check_matched + 112
6   libpython3.13.dylib           	       0x1039eebb8 warn_explicit + 1368
7   libpython3.13.dylib           	       0x1039f120c do_warn + 176
8   libpython3.13.dylib           	       0x1039ee158 PyErr_WarnFormat + 108
9   libpython3.13.dylib           	       0x10395549c _PyType_FromMetaclass_impl + 3940
10  _sentencepiece.cpython-313-darwin.so	       0x12a79e4a4 SwigPyPacked_TypeOnce() + 104
11  _sentencepiece.cpython-313-darwin.so	       0x12a77e738 PyInit__sentencepiece + 1244
12  libpython3.13.dylib           	       0x103ab0c38 _PyImport_RunModInitFunc + 100
13  libpython3.13.dylib           	       0x103aac6e0 import_run_extension + 192
14  libpython3.13.dylib           	       0x103aaf490 _imp_create_dynamic + 536
15  libpython3.13.dylib           	       0x103916d54 cfunction_vectorcall_FASTCALL + 280
16  libpython3.13.dylib           	       0x103a46eb0 _PyEval_EvalFrameDefault + 13948
-------- RECURSION LEVEL 9
17  libpython3.13.dylib           	       0x103893dc4 object_vacall + 428
18  libpython3.13.dylib           	       0x103893ac4 PyObject_CallMethodObjArgs + 124
19  libpython3.13.dylib           	       0x103aaa164 PyImport_ImportModuleLevelObject + 3048
20  libpython3.13.dylib           	       0x103a3b90c builtin___import__ + 316
21  libpython3.13.dylib           	       0x103916e68 cfunction_vectorcall_FASTCALL_KEYWORDS + 148
22  libpython3.13.dylib           	       0x103a46eb0 _PyEval_EvalFrameDefault + 13948
-------- RECURSION LEVEL 8

ninja: error: 'stdlib/public/core/SwiftMacros', needed by 'stdlib/public/core/OSX/arm64/Swift.o', missing and no known rule to make it

🤨

/nix/var/nix/builds/nix-build-swift-6.2.1.drv-0/b/swift/stdlib/toolchain/Compatibility56/include/Concurrency/VoucherShims.h:73:3: error: 'os_release' is only available on macOS 10.10 or newer >

nix/var/nix/builds/nix-build-swift-6.2.1.drv-0/b/swift/stdlib/public/core/SwiftNativeNSArray.swift:420:3: error: missing return in instance method expected to return 'R'
  }
  ^
/nix/var/nix/builds/nix-build-swift-6.2.1.drv-0/b/swift/stdlib/public/core/SwiftNativeNSArray.swift:474:3: error: missing return in instance method expected to return 'R'
  }
  ^

I applied a similar patch and got further.

swift> 1.       Swift version 6.2.1 (swift-6.2.1-RELEASE)
swift> 2.       Compiling with effective version 5.10
swift> 3.       While evaluating request ExecuteSILPipelineRequest(Run pipelines { PrepareOptimizationPasses, EarlyModulePasses, HighLevel,Function+EarlyLoopOpt, HighLevel,Module+StackPromote, MidLevel,Function, ClosureSpecialize, LowLevel,Function, LateLoopOpt, SIL Debug Info Generator } on SIL for _Concurrency)
swift> 4.       While running pass #509344 SILFunctionTransform "CodeSinking" on SILFunction "@$ss6_DequeV8_StorageV13_growCapacity2to8linearlyS2i_SbtFyt_Tg5".
swift>  for '_growCapacity(to:linearly:)' (at /nix/var/nix/builds/nix-build-swift-6.2.1.drv-0/b/swift/stdlib/public/Concurrency/Deque/Deque+Storage.swift:134:12)
swift> Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
swift> 0  libLLVM.dylib            0x000000011bcc085c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 72
swift> 1  libLLVM.dylib            0x000000011bcbe5a0 llvm::sys::RunSignalHandlers() + 108
swift> 2  libLLVM.dylib            0x000000011bcc0f38 SignalHandler(int, __siginfo*, void*) + 324
swift> 3  libsystem_platform.dylib 0x000000019e9cb744 _sigtramp + 56
swift> 4  swift-frontend           0x00000001089b130c (anonymous namespace)::CodeSinkingPass::sinkInstruction(swift::SILInstruction*) + 496
swift> 5  swift-frontend           0x00000001089b130c (anonymous namespace)::CodeSinkingPass::sinkInstruction(swift::SILInstruction*) + 496
swift> 6  swift-frontend           0x00000001089b1048 (anonymous namespace)::CodeSinkingPass::run() + 264
swift> 7  swift-frontend           0x00000001088a03b4 swift::SILPassManager::runFunctionPasses(unsigned int, unsigned int) + 6224
swift> 8  swift-frontend           0x000000010889db44 swift::SILPassManager::executePassPipelinePlan(swift::SILPassPipelinePlan const&) + 11880
swift> 9  swift-frontend           0x00000001088b880c swift::SimpleRequest<swift::ExecuteSILPipelineRequest, std::__1::tuple<> (swift::SILPipelineExecutionDescriptor), (swift::RequestFlags)1>::evaluateRequest(swift::ExecuteSILPipelineRequest const&, swift::Evaluator&) + 64
swift> 10 swift-frontend           0x00000001088a1638 swift::executePassPipelinePlan(swift::SILModule*, swift::SILPassPipelinePlan const&, bool, swift::irgen::IRGenModule*) + 380
swift> 11 swift-frontend           0x00000001088a4efc swift::runSILOptimizationPasses(swift::SILModule&) + 384
swift> 12 swift-frontend           0x0000000107f68c28 swift::CompilerInstance::performSILProcessing(swift::SILModule*) + 2540
swift> 13 swift-frontend           0x0000000107e10f94 performCompileStepsPostSILGen(swift::CompilerInstance&, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>>, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, swift::PrimarySpecificPaths const&, int&, swift::FrontendObserver*) + 1252
swift> 14 swift-frontend           0x0000000107e1020c swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 2336
swift> 15 swift-frontend           0x0000000107e23d90 performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 7868
swift> 16 swift-frontend           0x0000000107e2110c swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 6440
swift> 17 swift-frontend           0x0000000107da37dc swift::mainEntry(int, char const**) + 5564
swift> 18 dyld                     0x000000019e5f9d54 start + 7184
swift> <unknown>:0: error: unable to execute command: Segmentation fault: 11
swift> <unknown>:0: error: compile command failed due to signal 11 (use -v to see invocation)