One of fastlane's file (Fastfile) for my project

Fastfile

fastlane_version "2.81.0"

default_platform :ios

platform :ios do

  before_all do
    ENV["GITHUB_API_TOKEN="] ||= "YOUR GITHUB TOKEN"
    ENV["SLACK_URL"] ||= "YOU SLACK URI"
    ENV["CRASHLYTICS_API_TOKEN"] ||= "YOUR CRASHLYTICS_API_TOKEN"
    ENV["CRASHLYTICS_BUILD_SECRET"] ||= "YOUR CRASHLYTICS_BUILD_SECRET"
  end

  desc "Runs all the tests"
  lane :test do
    cocoapods
    carthage(verbose: true, platform: "iOS", use_binaries: false)
    scan
  end

  desc "Build App - Test [NO BUMPING VERSION]"
  lane :only_build_test_no_bump do
    config = "Test"
    cocoapods
    carthage(verbose: true, platform: "iOS", use_binaries: false)

    gym(
      scheme: "dtac One",
      configuration: config,
      output_name: "iosapp-#{config}.ipa",
      export_method: "ad-hoc"
    )
  end

  desc "Build App - Test [BUMP VERSION]"
  lane :build_test do
    increment_build_number
    only_build_test_no_bump
    crashlyticsBetaUpload(configuration: "Test")
    my_commit_version_bump
  end

  desc "Commit - the build number and push to git remote"
  lane :my_commit_version_bump do
    commit_version_bump(
      message: "📦 Build Number Bump to #{get_build_number}",
      xcodeproj: "iosapp.xcodeproj"
    )
    push_to_git_remote
  end

  desc "Upload - test app to crashlytics beta"
  lane :crashlyticsBetaUpload do |options|
    config = options[:configuration]
    config ||= "Test"

    commit = last_git_commit
    commit_message = commit[:message]

    git_commit_notes = changelog_from_git_commits(
      between: [last_git_tag, 'HEAD'],
      pretty: '• %s', 
      merge_commit_filtering: 'exclude_merges'
    )

    crashlytics(
      notes: git_commit_notes,
      ipa_path: "./build/iosapp-#{config}.ipa",
      groups: "atom",
      notifications: true
    )

    clean_build_artifacts
    rocket

    slack(
      payload: {
        'Lane' => "#{config}",
        'App Version' => "#{get_version_number} (#{get_build_number})",
        'Note' => git_commit_notes
      },
      default_payloads: [:git_branch, :git_author]
    )
  end

  desc "Deploy a new version to the Testflight"
  lane :build_testflight do
    ensure_git_status_clean

    cocoapods
    # carthage(verbose: true, platform: "iOS", use_binaries: false)s

    gym(
      scheme: "dtac One",
      configuration: "Release",
      output_name: "iosapp-Release.ipa",
      export_method: "app-store",
      include_bitcode: true
    )

    pilot(
      username: "phai@live.com",
      ipa: "./build/#{output_name}",
      skip_waiting_for_build_processing: true,
    )

    rocket

    git_commit_notes = changelog_from_git_commits(
      between: [last_git_tag, 'HEAD'],
      pretty: '• %s',
      merge_commit_filtering: 'exclude_merges'
    )

    set_github_release(
      repository_name: "PH9/iOSRTR",
      api_token: ENV["GITHUB_API_TOKEN"],
      name: "#{get_version_number} (#{get_build_number})",
      tag_name: "store/#{get_version_number}-#{get_build_number}",
      description: git_commit_notes,
      upload_assets: [
        lane_context[SharedValues::XCODEBUILD_ARCHIVE],
        lane_context[SharedValues::IPA_OUTPUT_PATH],
        lane_context[SharedValues::DSYM_OUTPUT_PATH]
      ],
      is_draft: false
    )

    # NO NEED TO UPLOAD SYMBOLS TO CRASHLYTICS ANYMORE AFTER ENABLING BITCODE
    # YOU SHOOLD `refresh_dsym` INSTEAD AFTER ITUNES CONNECT FINISH ITS PROCESS.
    # upload_symbols_to_crashlytics

    clean_build_artifacts
  end

  desc "Retry Upload release app - to itunes connect"
  lane :pilot_only do
    pilot(
      username: "phai@live.com",
      ipa: "./build/iosapp-Release.ipa",
      skip_waiting_for_build_processing: true,
    )

    rocket
  end

  desc "Download - only latest dsym from itunes connect and upload to crasglytics"
  lane :refresh_dsym do
    download_dsyms(version: 'latest')
    upload_symbols_to_crashlytics
    clean_build_artifacts
  end

  desc "Download - all dsyms from itunes connect and upload to crasglytics"
  lane :refresh_dsyms do
    download_dsyms
    upload_symbols_to_crashlytics
    clean_build_artifacts
  end

  desc "Download and refresh and profile"
  lane :sync_cert do
    match(type: "development", app_identifier: "com.github.ph9.iosapp.debug")
    match(type: "adhoc",       app_identifier: "com.github.ph9.iosapp.test")
    match(type: "appstore",    app_identifier: "com.github.ph9.iosapp", force_for_new_devices: false)
  end

  error do |lane, exception|
    slack(
      message: exception.message,
      success: false
    )
  end
end