diff --git a/.github/workflows/ci-2.x.yml b/.github/workflows/ci-2.x.yml
new file mode 100644
index 0000000..6339b60
--- /dev/null
+++ b/.github/workflows/ci-2.x.yml
@@ -0,0 +1,129 @@
+# Primary CI checks for Rollbar-PHP-Laravel.
+# We're checking that logging within Laravel passes through the Rollbar Laravel
+# integration when that integration is properly installed. We make this check
+# for all supported combinations of Laravel, Rollbar, and PHP. We are not
+# checking that messages are properly sent to Rollbar: that's handled by
+# rollbar-php.
+#
+# Test with act:
+#   brew install act
+#   act -P ubuntu-latest=shivammathur/node:latest
+#
+# @see https://github.com/nektos/act/issues/329
+name: Rollbar-PHP-Laravel CI, version 2.x
+
+# Fire this action on pushes to 2.x legacy branches (the official one, as well
+# as development branches within it -- hence the wildcard), and also tags for
+# the legacy lineage. Also, run every day at 02:42 GMT to catch failures from
+# transitive dependencies.
+
+on:
+  push:
+    branches:
+      - next/2.x/**
+    tags:
+      - v2.*
+  pull_request:
+    branches:
+      - next/2.x/**
+  schedule:
+    - cron: '42 2 * * *'
+
+jobs:
+  # Check that this runs on all combinations of Laravel we claim to support.
+  laravel-tests:
+    strategy:
+      matrix:
+        os: [ubuntu]
+        php: [7.4, 7.3, 7.2, 7.1, 7.0]
+        laravel: [^5.5]
+    env:
+      ROLLBAR_TOKEN: "ad865e76e7fb496fab096ac07b1dbabb"
+    name: Laravel ${{ matrix.laravel }} on PHP ${{ matrix.php }} (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}-latest
+    steps:
+      - name: Checkout the code
+        uses: actions/checkout@v2
+
+      - name: Install PHP and composer environment
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: curl
+
+      - name: Create Laravel test app
+        run: composer create-project laravel/laravel rollbar-test-app ${{ matrix.laravel }}
+
+      - name: Install that code using Composer rigged to look in the parent directory
+        working-directory: rollbar-test-app
+        run: |
+          composer config repositories.local '{"type":"path", "url":".."}'
+          composer require rollbar/rollbar-laravel
+          echo "ROLLBAR_TOKEN=${ROLLBAR_TOKEN}" >> .env
+          echo "GITHUB_RUN_ID=${GITHUB_RUN_ID}" >> .env
+          chmod 400 .env
+
+      - name: Configure Laravel to use Rollbar and configure Rollbar to invoke logging callback
+        working-directory: rollbar-test-app
+        run: |
+          > config/logging.php echo '<?php return array (
+              "default" => "rollbar",
+              "channels" => array (
+                "rollbar" => array (
+                  "driver" => "monolog",
+                  "handler" => \Rollbar\Laravel\MonologHandler::class,
+                  "access_token" => env("ROLLBAR_TOKEN"),
+                  "level" => "debug",
+                  // use the check_ignore filter to capture log messages for verification
+                  "check_ignore" => "check_ignore",
+                )
+              )
+            );
+          '
+          touch app/helpers.php
+          > tmp-composer.json jq '.autoload += { "files": [ "app/helpers.php" ] }' composer.json
+          mv tmp-composer.json composer.json
+          composer dump-autoload
+
+      - name: Define logging callback that invokes when Laravel logs through Rollbar
+        working-directory: rollbar-test-app
+        run: |
+          > app/helpers.php echo '<?php
+            function temp_file() {
+              return env("RUNNER_TEMP") . DIRECTORY_SEPARATOR . env("GITHUB_RUN_ID") . ".tmp.txt";
+            }
+            function check_ignore($isUncaught, $toLog, $payload) {
+              // write log message to a file for inspection
+              $ok = file_put_contents(temp_file(), (string)$toLog);
+              // return indication that the log should be dropped
+              return true;
+            }
+          '
+
+      - name: Define Laravel tests to exercise and verify logging
+        working-directory: rollbar-test-app
+        run: |
+          > tests/Feature/LoggingTest.php echo '<?php
+            namespace Tests\Feature;
+            class LoggingTest extends \Tests\TestCase {
+              public function test_log_call_invokes_rollbar_check_ignore()
+              {
+                // generate a random valued log message to check it is passed through the
+                // Laravel logging mechanism into Rollbar
+                $value = sprintf("%s-%s", env("GITHUB_RUN_ID"), rand());
+
+                \Log::error($value);
+
+                // check that we have our random value written into our local file
+                $this->assertFileExists(temp_file(),
+                  "Rollbar check_ignore handler not invoked, suggesting an issue integrating Rollbar into Laravel.");
+                $this->assertSame($value, file_get_contents(temp_file()),
+                  "check_ignore file did not contain expected value, suggesting file left by another process.");
+              }
+            }
+          '
+
+      - name: Invoke the Laravel test suite
+        working-directory: rollbar-test-app
+        run: |
+          ./vendor/bin/phpunit
diff --git a/.github/workflows/ci-4.x.yml b/.github/workflows/ci-4.x.yml
new file mode 100644
index 0000000..d8235c3
--- /dev/null
+++ b/.github/workflows/ci-4.x.yml
@@ -0,0 +1,129 @@
+# Primary CI checks for Rollbar-PHP-Laravel.
+# We're checking that logging within Laravel passes through the Rollbar Laravel
+# integration when that integration is properly installed. We make this check
+# for all supported combinations of Laravel, Rollbar, and PHP. We are not
+# checking that messages are properly sent to Rollbar: that's handled by
+# rollbar-php.
+#
+# Test with act:
+#   brew install act
+#   act -P ubuntu-latest=shivammathur/node:latest
+#
+# @see https://github.com/nektos/act/issues/329
+name: Rollbar-PHP-Laravel CI, version 4.x
+
+# Fire this action on pushes to 4.x legacy branches (the official one, as well
+# as development branches within it -- hence the wildcard), and also tags for
+# the legacy lineage. Also, run every day at 02:42 GMT to catch failures from
+# transitive dependencies.
+
+on:
+  push:
+    branches:
+      - next/4.x/**
+    tags:
+      - v4.*
+  pull_request:
+    branches:
+      - next/4.x/**
+  schedule:
+    - cron: '42 2 * * *'
+
+jobs:
+  # Check that this runs on all combinations of Laravel we claim to support.
+  laravel-tests:
+    strategy:
+      matrix:
+        os: [ubuntu]
+        php: [7.4, 7.3, 7.2, 7.1]
+        laravel: [^5.8, ^5.7, ^5.6]
+    env:
+      ROLLBAR_TOKEN: "ad865e76e7fb496fab096ac07b1dbabb"
+    name: Laravel ${{ matrix.laravel }} on PHP ${{ matrix.php }} (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}-latest
+    steps:
+      - name: Checkout the code
+        uses: actions/checkout@v2
+
+      - name: Install PHP and composer environment
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: curl
+
+      - name: Create Laravel test app
+        run: composer create-project laravel/laravel rollbar-test-app ${{ matrix.laravel }}
+
+      - name: Install that code using Composer rigged to look in the parent directory
+        working-directory: rollbar-test-app
+        run: |
+          composer config repositories.local '{"type":"path", "url":".."}'
+          composer require rollbar/rollbar-laravel
+          echo "ROLLBAR_TOKEN=${ROLLBAR_TOKEN}" >> .env
+          echo "GITHUB_RUN_ID=${GITHUB_RUN_ID}" >> .env
+          chmod 400 .env
+
+      - name: Configure Laravel to use Rollbar and configure Rollbar to invoke logging callback
+        working-directory: rollbar-test-app
+        run: |
+          > config/logging.php echo '<?php return array (
+              "default" => "rollbar",
+              "channels" => array (
+                "rollbar" => array (
+                  "driver" => "monolog",
+                  "handler" => \Rollbar\Laravel\MonologHandler::class,
+                  "access_token" => env("ROLLBAR_TOKEN"),
+                  "level" => "debug",
+                  // use the check_ignore filter to capture log messages for verification
+                  "check_ignore" => "check_ignore",
+                )
+              )
+            );
+          '
+          touch app/helpers.php
+          > tmp-composer.json jq '.autoload += { "files": [ "app/helpers.php" ] }' composer.json
+          mv tmp-composer.json composer.json
+          composer dump-autoload
+
+      - name: Define logging callback that invokes when Laravel logs through Rollbar
+        working-directory: rollbar-test-app
+        run: |
+          > app/helpers.php echo '<?php
+            function temp_file() {
+              return env("RUNNER_TEMP") . DIRECTORY_SEPARATOR . env("GITHUB_RUN_ID") . ".tmp.txt";
+            }
+            function check_ignore($isUncaught, $toLog, $payload) {
+              // write log message to a file for inspection
+              $ok = file_put_contents(temp_file(), (string)$toLog);
+              // return indication that the log should be dropped
+              return true;
+            }
+          '
+
+      - name: Define Laravel tests to exercise and verify logging
+        working-directory: rollbar-test-app
+        run: |
+          > tests/Feature/LoggingTest.php echo '<?php
+            namespace Tests\Feature;
+            class LoggingTest extends \Tests\TestCase {
+              public function test_log_call_invokes_rollbar_check_ignore()
+              {
+                // generate a random valued log message to check it is passed through the
+                // Laravel logging mechanism into Rollbar
+                $value = sprintf("%s-%s", env("GITHUB_RUN_ID"), rand());
+
+                \Log::error($value);
+
+                // check that we have our random value written into our local file
+                $this->assertFileExists(temp_file(),
+                  "Rollbar check_ignore handler not invoked, suggesting an issue integrating Rollbar into Laravel.");
+                $this->assertSame($value, file_get_contents(temp_file()),
+                  "check_ignore file did not contain expected value, suggesting file left by another process.");
+              }
+            }
+          '
+
+      - name: Invoke the Laravel test suite
+        working-directory: rollbar-test-app
+        run: |
+          ./vendor/bin/phpunit
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4affb99..c10ea76 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,37 +1,45 @@
 # Primary CI checks for Rollbar-PHP-Laravel.
+# We're checking that logging within Laravel passes through the Rollbar Laravel
+# integration when that integration is properly installed. We make this check
+# for all supported combinations of Laravel, Rollbar, and PHP. We are not
+# checking that messages are properly sent to Rollbar: that's handled by
+# rollbar-php.
 #
 # Test with act:
 #   brew install act
 #   act -P ubuntu-latest=shivammathur/node:latest
 #
 # @see https://github.com/nektos/act/issues/329
-name: Rollbar-PHP-Laravel CI
+name: Rollbar-PHP-Laravel CI, master
 
 # Fire this action on pushes to main branch (master) as well as other branches
-# or pull requests. Also, run every day at 02:42 GMT -- this catches failures
-# from dependencies that update indepdently.
+# or pull requests, excluding those in the next/ lineage. Also, run every day
+# at 02:42 GMT -- this catches failures from transitive dependencies.
 on:
   push:
+    branches-ignore:
+      - next/**
   pull_request:
+    branches-ignore:
+      - next/**
   schedule:
     - cron: '42 2 * * *'
 
 jobs:
-  # Check that this runs on PHP on all versions we claim to support, on both
-  # UNIX-like and Windows environments, and that use both the lowest possible
-  # compatible version as well as the most-recent stable version. This will
-  # fail-fast by default, so we include our edgiest versions (currently 7.4)
-  # first as they're most likely to fail.
-  # @seealso https://freek.dev/1546
-  # @seealso https://www.dereuromark.de/2019/01/04/test-composer-dependencies-with-prefer-lowest/
-  php-tests:
+  # Check that this runs on all combinations of Laravel we claim to support.
+  laravel-tests:
     strategy:
       matrix:
-        php: [7.3, 7.2]
-        dependency: [stable]
         os: [ubuntu]
-
-    name: PHP ${{ matrix.php }} on ${{ matrix.os }}, ${{ matrix.dependency }} dependencies preferred
+        php: [7.4, 7.3, 7.2]
+        laravel: [^8, ^7, ^6]
+        exclude:
+          # Laravel 8 requires php 7.3+, so exclude all PHP versions prior to 7.3
+          - laravel: ^8
+            php: 7.2
+    env:
+      ROLLBAR_TOKEN: "ad865e76e7fb496fab096ac07b1dbabb"
+    name: Laravel ${{ matrix.laravel }} on PHP ${{ matrix.php }} (${{ matrix.os }})
     runs-on: ${{ matrix.os }}-latest
     steps:
       - name: Checkout the code
@@ -42,29 +50,80 @@ jobs:
         with:
           php-version: ${{ matrix.php }}
           extensions: curl
-          ini-values: ${{ matrix.ini }}
-          coverage: xdebug
 
-      - name: Get composer cache directory
-        id: composer-cache
-        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+      - name: Create Laravel test app
+        run: composer create-project laravel/laravel rollbar-test-app ${{ matrix.laravel }}
 
-      - name: Cache dependencies
-        uses: actions/cache@v2
-        with:
-          path: ${{ steps.composer-cache.outputs.dir }}
-          key: ${{ matrix.os }}-composer-${{ hashFiles('**/composer.json') }}-${{ matrix.dependency }}-
-          restore-keys: ${{ matrix.os }}-composer-${{ matrix.dependency }}-
+      - name: Install that code using Composer rigged to look in the parent directory
+        working-directory: rollbar-test-app
+        run: |
+          composer config repositories.local '{"type":"path", "url":".."}'
+          composer require rollbar/rollbar-laravel
+          echo "ROLLBAR_TOKEN=${ROLLBAR_TOKEN}" >> .env
+          echo "GITHUB_RUN_ID=${GITHUB_RUN_ID}" >> .env
+          chmod 400 .env
+
+      - name: Configure Laravel to use Rollbar and configure Rollbar to invoke logging callback
+        working-directory: rollbar-test-app
+        run: |
+          > config/logging.php echo '<?php return array (
+              "default" => "rollbar",
+              "channels" => array (
+                "rollbar" => array (
+                  "driver" => "monolog",
+                  "handler" => \Rollbar\Laravel\MonologHandler::class,
+                  "access_token" => env("ROLLBAR_TOKEN"),
+                  "level" => "debug",
+                  // use the check_ignore filter to capture log messages for verification
+                  "check_ignore" => "check_ignore",
+                )
+              )
+            );
+          '
+          touch app/helpers.php
+          > tmp-composer.json jq '.autoload += { "files": [ "app/helpers.php" ] }' composer.json
+          mv tmp-composer.json composer.json
+          composer dump-autoload
+
+      - name: Define logging callback that invokes when Laravel logs through Rollbar
+        working-directory: rollbar-test-app
+        run: |
+          > app/helpers.php echo '<?php
+            function temp_file() {
+              return env("RUNNER_TEMP") . DIRECTORY_SEPARATOR . env("GITHUB_RUN_ID") . ".tmp.txt";
+            }
+            function check_ignore($isUncaught, $toLog, $payload) {
+              // write log message to a file for inspection
+              $ok = file_put_contents(temp_file(), (string)$toLog);
+              // return indication that the log should be dropped
+              return true;
+            }
+          '
 
-      - name: Install dependencies
-        run: composer update --prefer-${{ matrix.dependency }} --prefer-dist --no-interaction
+      - name: Define Laravel tests to exercise and verify logging
+        working-directory: rollbar-test-app
+        run: |
+          > tests/Feature/LoggingTest.php echo '<?php
+            namespace Tests\Feature;
+            class LoggingTest extends \Tests\TestCase {
+              public function test_log_call_invokes_rollbar_check_ignore()
+              {
+                // generate a random valued log message to check it is passed through the
+                // Laravel logging mechanism into Rollbar
+                $value = sprintf("%s-%s", env("GITHUB_RUN_ID"), rand());
 
-      - name: Make logs directory
-        run: mkdir -p build/logs
+                \Log::error($value);
 
-      - name: Execute tests
-        run: composer test
+                // check that we have our random value written into our local file
+                $this->assertFileExists(temp_file(),
+                  "Rollbar check_ignore handler not invoked, suggesting an issue integrating Rollbar into Laravel.");
+                $this->assertSame($value, file_get_contents(temp_file()),
+                  "check_ignore file did not contain expected value, suggesting file left by another process.");
+              }
+            }
+          '
 
-      - name: Report results
-        if: success()
-        run: ./vendor/bin/php-coveralls -v || true
+      - name: Invoke the Laravel test suite
+        working-directory: rollbar-test-app
+        run: |
+          ./vendor/bin/phpunit