The build failure was due to the dblurt package link.

Thanks to jacob, I can replace gitlab repo to npm package like this
https://www.npmjs.com/package/dblurt

before

package.json

dependencies: {
      "dblurt": "gitlab:blurt/openblurt/dblurt",
}

after

package.json

dependencies: {
    "dblurt": "0.1.2",
}

Then, install depedencies by yarn.

$ yarn

---

Deprecated

I tried to build the letsblurt app today but it failed.

I don't know the reason. but I succeeded to build the app by following procedure:

1. delete node_modules

2. remove dblurt dependency in package.json

"dblurt": "gitlab:blurt/openblurt/dblurt",

3. install dependencies using yarn

$ yarn

4. try install again this using npm

$ npm install

5. add dblurt dependency in package.json

    "dblurt": "gitlab:blurt/openblurt/dblurt",

6. install dependencies using npm

$ npm install

I know the gitlab:blurt is only supported in npm. but I don't know why npm installing caused errors which are not relevant such as firebase/auth errror.

Update

I can do simply the following:

$ npm install --force

---

Another build issue:
https://stackoverflow.com/questions/60919046/how-to-fix-build-gradle

java.nio.file.NoSuchFileException: /Users/etainclub/devel-src/letsblurt/letsblurt/android/app/build/intermediates/external_file_lib_dex_archives/debug/out
    at sun.nio.fs.UnixException.translateToIOException(UnixException.java:86)

So I did the following:

$ rm -rf android/.gradle android/.idea

For android, it works!

https://stackoverflow.com/questions/39876829/apk-failing-to-install-on-android-n-with-install-failed-invalid-apk-error

ios works too!