Weak linking static library in Xcode

I’m trying to achieve weak linking with static libraries. I’ve read those two articles, "Static Library on iOS" and "How Jesse Pinkman cracked Dynamic Library on iOS", which are really helpful.

However, I’m in a situation that I cannot achieve what I want. I’ve developed two frameworks, let’s call them Main and Feature, they can be installed both as pods and swift packages.

Main doesn’t have a dependency on Feature, nor Feature on Main, but if both Main and Feature are present on the podfile of the developer, then Main can use Feature’s functionality. This is achieved by adding the Framework’s path on the Main’s framework search paths in its podspec.

Main.podspec

# This works when use_frameworks! is added in the podfile.
s.pod_target_xcconfig = {
    "FRAMEWORK_SEARCH_PATHS" => [
      "$(inherited)",
      "${PODS_CONFIGURATION_BUILD_DIR}/Feature",
    ],
}

This way, Main can use Feature’s functionality the following way

#if canImport(Feature)
print("SUCCESS!!!")
let feat = Feature()
feat.test()
#else
print(“Failed to import Feature“)
#endif

The problem starts when the integrating developer doesn’t include use_frameworks! In his podfile (e.g. React Native). Main and Feature are then built as static libraries, it compiles but it never gets inside the SUCCESS block.

After reading the above articles, I believe that the correct approach would be something like the following

Main.podspec

s.pod_target_xcconfig = {
    "LIBRARY_SEARCH_PATHS" => [
      "$(inherited)",
      "${PODS_CONFIGURATION_BUILD_DIR}/Feature",
    ],
    "SWIFT_INCLUDE_PATHS" => [
        "$(inherited)",
        "${PODS_CONFIGURATION_BUILD_DIR}/Feature",
    ],
  }

And maybe also add

  Main.podspec

  s.pod_target_xcconfig = {
   …
    'OTHER_LDFLAGS' => [
        "$(inherited)",
        '-ObjC',
        '-weak_library -l"Feature"'
    ],
    …
  }

I’ve tried the above with both Defines module = YES/NO on the Feature‘s side.

Feature.podspec

s.pod_target_xcconfig = {
    'DEFINES_MODULE' => 'YES'
}

However, none of the above worked. Does anyone have any idea of what I might be doing wrong, or point me in some direction?