diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 75eec787..44f9e305 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -162,3 +162,41 @@ jobs:
           BASILISP_TEST_PATH="$(pwd)/test" \
             BASILISP_TEST_FILE_PATTERN='.*\.(lpy|cljc)' \
             basilisp test -p test -- -n 0
+
+  test-phel:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        php: ['8.4', '8.5']
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          coverage: none
+          tools: composer
+
+      - name: Cache Composer downloads
+        uses: actions/cache@v4
+        with:
+          path: ~/.composer/cache
+          key: composer-${{ matrix.php }}-${{ hashFiles('composer.lock') }}
+          restore-keys: |
+            composer-${{ matrix.php }}-
+
+      - name: Cache Phel compiled artifacts
+        uses: actions/cache@v4
+        with:
+          path: .phel/cache
+          key: phel-cache-${{ matrix.php }}-${{ hashFiles('composer.lock', 'phel-config.php') }}-${{ hashFiles('test/**/*.cljc', 'test/**/*.phel') }}
+          restore-keys: |
+            phel-cache-${{ matrix.php }}-${{ hashFiles('composer.lock', 'phel-config.php') }}-
+            phel-cache-${{ matrix.php }}-
+
+      - name: Install dependencies
+        run: composer install --no-interaction --no-ansi --no-progress
+
+      - name: Run tests
+        run: composer test
diff --git a/.gitignore b/.gitignore
index 7ac80714..19c5016f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -28,3 +28,4 @@ __pycache__/
 poetry.lock
 *.egg-info/
 .DS_Store
+/vendor/
diff --git a/README.md b/README.md
index caa85cac..c7d47a12 100644
--- a/README.md
+++ b/README.md
@@ -22,3 +22,4 @@ See these documents for how to set up individual dialect-specific environments a
 3. [Babashka](doc/babashka.md)
 4. [Clojure CLR](doc/clojureclr.md)
 5. [Basilisp](doc/basilisp.md)
+6. [Phel](doc/phel.md)
diff --git a/bb.edn b/bb.edn
index 7c466250..15e70b67 100644
--- a/bb.edn
+++ b/bb.edn
@@ -32,13 +32,18 @@
                     {:extra-env {"BASILISP_TEST_PATH"         "./test"
                                  "BASILISP_TEST_FILE_PATTERN" ".*\\.(lpy|cljc)"}}
                     "basilisp test -p test -- -n 0"))}
+  test-phel {:doc "Runs tests in Phel"
+             :task (do
+                    (banner "Running Phel Tests")
+                    (shell "composer test"))}
   test-all {:doc "Run tests under all dialects"
             :task (do
                    (run 'test-jvm)
                    (run 'test-cljs)
                    (run 'test-bb)
-                   (run 'test-lpy))}
-  test {:doc "Runs tests in multiple named dialects: jvm, bb, cljs, or lpy"
+                   (run 'test-lpy)
+                   (run 'test-phel))}
+  test {:doc "Runs tests in multiple named dialects: jvm, bb, cljs, lpy, or phel"
         :task (letfn [(help []
                        (println "Usage: bb test <dialect1> [<dialect2>]...")
                        (println "Where <dialect> is one of:")
@@ -46,9 +51,10 @@
                        (println "  cljs    Runs tests in ClojureScript")
                        (println "  bb      Runs tests in Babashka")
                        (println "  lpy     Runs tests in Basilisp")
+                       (println "  phel    Runs tests in Phel")
                        (println "  all     Runs tests in all supported dialects")
                        (println "Tests are run in the order given."))]
-               (let [valid #{"jvm" "cljs" "bb" "lpy" "all"}
+               (let [valid #{"jvm" "cljs" "bb" "lpy" "phel" "all"}
                      unknown (remove valid *command-line-args*)]
                 (cond
                  (not (some? (seq *command-line-args*)))
@@ -69,7 +75,8 @@
                    "jvm" (run 'test-jvm)
                    "cljs" (run 'test-cljs)
                    "bb" (run 'test-bb)
-                   "lpy" (run 'test-lpy))))))}
+                   "lpy" (run 'test-lpy)
+                   "phel" (run 'test-phel))))))}
   new-test {:doc "Creates new test for the Clojure symbols named by <args>. Unqualified symbols assume clojure.core"
             :requires ([new-test])
             :task (new-test/new-test *command-line-args*)}}}
diff --git a/composer.json b/composer.json
new file mode 100644
index 00000000..03f6195b
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,8 @@
+{
+    "require": {
+        "phel-lang/phel-lang": "^0.37"
+    },
+    "scripts": {
+        "test": "XDEBUG_MODE=off ./vendor/bin/phel test"
+    }
+}
diff --git a/composer.lock b/composer.lock
new file mode 100644
index 00000000..343aee07
--- /dev/null
+++ b/composer.lock
@@ -0,0 +1,1216 @@
+{
+    "_readme": [
+        "This file locks the dependencies of your project to a known state",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+        "This file is @generated automatically"
+    ],
+    "content-hash": "a715e87fd47198697005d49d2c3a63e4",
+    "packages": [
+        {
+            "name": "amphp/amp",
+            "version": "v3.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/amphp/amp.git",
+                "reference": "fa0ab33a6f47a82929c38d03ca47ebb71086a93f"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/amphp/amp/zipball/fa0ab33a6f47a82929c38d03ca47ebb71086a93f",
+                "reference": "fa0ab33a6f47a82929c38d03ca47ebb71086a93f",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1",
+                "revolt/event-loop": "^1 || ^0.2"
+            },
+            "require-dev": {
+                "amphp/php-cs-fixer-config": "^2",
+                "phpunit/phpunit": "^9",
+                "psalm/phar": "5.23.1"
+            },
+            "type": "library",
+            "autoload": {
+                "files": [
+                    "src/functions.php",
+                    "src/Future/functions.php",
+                    "src/Internal/functions.php"
+                ],
+                "psr-4": {
+                    "Amp\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Aaron Piotrowski",
+                    "email": "aaron@trowski.com"
+                },
+                {
+                    "name": "Bob Weinand",
+                    "email": "bobwei9@hotmail.com"
+                },
+                {
+                    "name": "Niklas Keller",
+                    "email": "me@kelunik.com"
+                },
+                {
+                    "name": "Daniel Lowrey",
+                    "email": "rdlowrey@php.net"
+                }
+            ],
+            "description": "A non-blocking concurrency framework for PHP applications.",
+            "homepage": "https://amphp.org/amp",
+            "keywords": [
+                "async",
+                "asynchronous",
+                "awaitable",
+                "concurrency",
+                "event",
+                "event-loop",
+                "future",
+                "non-blocking",
+                "promise"
+            ],
+            "support": {
+                "issues": "https://github.com/amphp/amp/issues",
+                "source": "https://github.com/amphp/amp/tree/v3.1.1"
+            },
+            "funding": [
+                {
+                    "url": "https://github.com/amphp",
+                    "type": "github"
+                }
+            ],
+            "time": "2025-08-27T21:42:00+00:00"
+        },
+        {
+            "name": "gacela-project/container",
+            "version": "0.8.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/gacela-project/container.git",
+                "reference": "62a409c918fe0e301b909da1c54aea189bd6e76a"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/gacela-project/container/zipball/62a409c918fe0e301b909da1c54aea189bd6e76a",
+                "reference": "62a409c918fe0e301b909da1c54aea189bd6e76a",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1",
+                "psr/container": ">=1.1"
+            },
+            "require-dev": {
+                "friendsofphp/php-cs-fixer": "^3.75",
+                "phpstan/phpstan": "^1.12",
+                "phpunit/phpunit": "^10.5",
+                "psalm/plugin-phpunit": "^0.18",
+                "symfony/var-dumper": "^5.4",
+                "vimeo/psalm": "^5.26"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Gacela\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jose Maria Valera Reales",
+                    "email": "chemaclass@outlook.es",
+                    "homepage": "https://chemaclass.com"
+                },
+                {
+                    "name": "Jesus Valera Reales",
+                    "email": "hello@jesusvalera.dev",
+                    "homepage": "https://jesusvalera.dev/"
+                }
+            ],
+            "description": "A minimalistic container dependency resolver",
+            "homepage": "https://gacela-project.com",
+            "keywords": [
+                "container",
+                "gacela",
+                "php",
+                "resolver"
+            ],
+            "support": {
+                "issues": "https://github.com/gacela-project/resolver/issues",
+                "source": "https://github.com/gacela-project/container/tree/0.8.0"
+            },
+            "funding": [
+                {
+                    "url": "https://chemaclass.com/sponsor",
+                    "type": "custom"
+                }
+            ],
+            "time": "2025-11-08T22:36:48+00:00"
+        },
+        {
+            "name": "gacela-project/gacela",
+            "version": "1.14.4",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/gacela-project/gacela.git",
+                "reference": "d3058fa16b4748adca17d7e5b940c0dc5daa3e61"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/gacela-project/gacela/zipball/d3058fa16b4748adca17d7e5b940c0dc5daa3e61",
+                "reference": "d3058fa16b4748adca17d7e5b940c0dc5daa3e61",
+                "shasum": ""
+            },
+            "require": {
+                "gacela-project/container": "^0.8",
+                "php": ">=8.1"
+            },
+            "require-dev": {
+                "ergebnis/composer-normalize": "^2.50",
+                "friendsofphp/php-cs-fixer": "^3.95",
+                "infection/infection": "^0.29",
+                "phpbench/phpbench": "^1.4",
+                "phpmetrics/phpmetrics": "^2.9",
+                "phpstan/phpstan": "^2.0",
+                "phpstan/phpstan-strict-rules": "^2.0",
+                "phpunit/phpunit": "^10.5",
+                "psalm/plugin-phpunit": "^0.19.5",
+                "rector/rector": "^2.0",
+                "symfony/console": "^6.4",
+                "symfony/dependency-injection": "^6.4",
+                "symfony/var-dumper": "^6.4",
+                "vimeo/psalm": "^6.16"
+            },
+            "suggest": {
+                "gacela-project/gacela-env-config-reader": "Allows to read .env config files",
+                "gacela-project/gacela-yaml-config-reader": "Allows to read yml/yaml config files",
+                "gacela-project/phpstan-extension": "A set of phpstan rules for Gacela",
+                "symfony/console": "Allows to use vendor/bin/gacela script"
+            },
+            "bin": [
+                "bin/gacela"
+            ],
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Gacela\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jose Maria Valera Reales",
+                    "email": "chemaclass@outlook.es",
+                    "homepage": "https://chemaclass.com"
+                },
+                {
+                    "name": "Jesus Valera Reales",
+                    "email": "hello@jesusvalera.dev",
+                    "homepage": "https://jesusvalera.dev/"
+                }
+            ],
+            "description": "Gacela helps you separate your project into modules",
+            "homepage": "https://gacela-project.com",
+            "keywords": [
+                "framework",
+                "kernel",
+                "modular",
+                "php"
+            ],
+            "support": {
+                "issues": "https://github.com/gacela-project/gacela/issues",
+                "source": "https://github.com/gacela-project/gacela/tree/1.14.4"
+            },
+            "funding": [
+                {
+                    "url": "https://chemaclass.com/sponsor",
+                    "type": "custom"
+                }
+            ],
+            "time": "2026-04-20T09:41:26+00:00"
+        },
+        {
+            "name": "phel-lang/phel-lang",
+            "version": "v0.37.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/phel-lang/phel-lang.git",
+                "reference": "091e9be0ff0f52ccfb4340e6776db1243ef96933"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/phel-lang/phel-lang/zipball/091e9be0ff0f52ccfb4340e6776db1243ef96933",
+                "reference": "091e9be0ff0f52ccfb4340e6776db1243ef96933",
+                "shasum": ""
+            },
+            "require": {
+                "amphp/amp": "^3.1",
+                "gacela-project/gacela": "^1.14",
+                "php": ">=8.4",
+                "symfony/console": "^6.0|^7.0|^8.0",
+                "symfony/routing": "^7.3"
+            },
+            "require-dev": {
+                "ergebnis/composer-normalize": "^2.50",
+                "ext-readline": "*",
+                "friendsofphp/php-cs-fixer": "^3.94",
+                "phpbench/phpbench": "^1.6",
+                "phpstan/phpstan": "^2.1",
+                "phpunit/phpunit": "^10.5",
+                "psalm/plugin-phpunit": "^0.19",
+                "rector/rector": "^2.3",
+                "symfony/var-dumper": "^7.4",
+                "vimeo/psalm": "^6.16"
+            },
+            "bin": [
+                "bin/phel"
+            ],
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Phel\\": "src/php/"
+                },
+                "classmap": [
+                    "src/Phel.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Jens Haase",
+                    "email": "je.haase@gmail.com"
+                },
+                {
+                    "name": "Jose M. Valera Reales",
+                    "email": "phel@chemaclass.es",
+                    "homepage": "https://chemaclass.com"
+                }
+            ],
+            "description": "Phel is a functional programming language that compiles to PHP",
+            "homepage": "https://phel-lang.org/",
+            "keywords": [
+                "functional",
+                "language",
+                "lisp",
+                "phel"
+            ],
+            "support": {
+                "issues": "https://github.com/phel-lang/phel-lang/issues",
+                "source": "https://github.com/phel-lang/phel-lang/tree/v0.37.0"
+            },
+            "funding": [
+                {
+                    "url": "https://chemaclass.com/sponsor",
+                    "type": "custom"
+                }
+            ],
+            "time": "2026-05-12T13:13:01+00:00"
+        },
+        {
+            "name": "psr/container",
+            "version": "2.0.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/php-fig/container.git",
+                "reference": "c71ecc56dfe541dbd90c5360474fbc405f8d5963"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/php-fig/container/zipball/c71ecc56dfe541dbd90c5360474fbc405f8d5963",
+                "reference": "c71ecc56dfe541dbd90c5360474fbc405f8d5963",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7.4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.0.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Psr\\Container\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "PHP-FIG",
+                    "homepage": "https://www.php-fig.org/"
+                }
+            ],
+            "description": "Common Container Interface (PHP FIG PSR-11)",
+            "homepage": "https://github.com/php-fig/container",
+            "keywords": [
+                "PSR-11",
+                "container",
+                "container-interface",
+                "container-interop",
+                "psr"
+            ],
+            "support": {
+                "issues": "https://github.com/php-fig/container/issues",
+                "source": "https://github.com/php-fig/container/tree/2.0.2"
+            },
+            "time": "2021-11-05T16:47:00+00:00"
+        },
+        {
+            "name": "revolt/event-loop",
+            "version": "v1.0.8",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/revoltphp/event-loop.git",
+                "reference": "b6fc06dce8e9b523c9946138fa5e62181934f91c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/revoltphp/event-loop/zipball/b6fc06dce8e9b523c9946138fa5e62181934f91c",
+                "reference": "b6fc06dce8e9b523c9946138fa5e62181934f91c",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.1"
+            },
+            "require-dev": {
+                "ext-json": "*",
+                "jetbrains/phpstorm-stubs": "^2019.3",
+                "phpunit/phpunit": "^9",
+                "psalm/phar": "^5.15"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-main": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Revolt\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Aaron Piotrowski",
+                    "email": "aaron@trowski.com"
+                },
+                {
+                    "name": "Cees-Jan Kiewiet",
+                    "email": "ceesjank@gmail.com"
+                },
+                {
+                    "name": "Christian Lück",
+                    "email": "christian@clue.engineering"
+                },
+                {
+                    "name": "Niklas Keller",
+                    "email": "me@kelunik.com"
+                }
+            ],
+            "description": "Rock-solid event loop for concurrent PHP applications.",
+            "keywords": [
+                "async",
+                "asynchronous",
+                "concurrency",
+                "event",
+                "event-loop",
+                "non-blocking",
+                "scheduler"
+            ],
+            "support": {
+                "issues": "https://github.com/revoltphp/event-loop/issues",
+                "source": "https://github.com/revoltphp/event-loop/tree/v1.0.8"
+            },
+            "time": "2025-08-27T21:33:23+00:00"
+        },
+        {
+            "name": "symfony/console",
+            "version": "v8.0.11",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/console.git",
+                "reference": "3156577f46a38aa1b9323aad223de7a9cd426782"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/console/zipball/3156577f46a38aa1b9323aad223de7a9cd426782",
+                "reference": "3156577f46a38aa1b9323aad223de7a9cd426782",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=8.4",
+                "symfony/polyfill-mbstring": "^1.0",
+                "symfony/service-contracts": "^2.5|^3",
+                "symfony/string": "^7.4|^8.0"
+            },
+            "provide": {
+                "psr/log-implementation": "1.0|2.0|3.0"
+            },
+            "require-dev": {
+                "psr/log": "^1|^2|^3",
+                "symfony/config": "^7.4|^8.0",
+                "symfony/dependency-injection": "^7.4|^8.0",
+                "symfony/event-dispatcher": "^7.4|^8.0",
+                "symfony/http-foundation": "^7.4|^8.0",
+                "symfony/http-kernel": "^7.4|^8.0",
+                "symfony/lock": "^7.4|^8.0",
+                "symfony/messenger": "^7.4|^8.0",
+                "symfony/process": "^7.4|^8.0",
+                "symfony/stopwatch": "^7.4|^8.0",
+                "symfony/var-dumper": "^7.4|^8.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Component\\Console\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Tests/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Fabien Potencier",
+                    "email": "fabien@symfony.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Eases the creation of beautiful and testable command line interfaces",
+            "homepage": "https://symfony.com",
+            "keywords": [
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+}
diff --git a/doc/phel.md b/doc/phel.md
new file mode 100644
index 00000000..0d6f4d78
--- /dev/null
+++ b/doc/phel.md
@@ -0,0 +1,102 @@
+# Running the Phel tests
+
+## Prerequisites
+
+- PHP 8.4+ (`php -v` to check)
+- [Composer](https://getcomposer.org/doc/00-intro.md#installation-linux-unix-macos)
+
+Install dependencies:
+
+```bash
+composer install
+```
+
+Tests live in `test/` (configurable in [`phel-config.php`](../phel-config.php) via `withTestDirs`).
+
+See also the [Phel Getting Started guide](https://phel-lang.org/documentation/getting-started/).
+
+## Running the test suite
+
+Full suite:
+
+```bash
+composer test
+```
+
+A single file:
+
+```bash
+composer test -- test/clojure/core_test/abs.cljc
+```
+
+A namespace:
+
+```bash
+composer test -- --filter clojure.core-test.abs
+```
+
+> The `composer test` script sets `XDEBUG_MODE=off`, which makes startup
+> noticeably faster than calling `./vendor/bin/phel test` directly when
+> Xdebug is installed system-wide.
+
+If the runner crashes before printing a report, re-run with `--testdox` or `-v` to locate the failing test.
+
+See the [Phel testing docs](https://phel-lang.org/documentation/testing/#running-tests).
+
+## Formatting
+
+Format the test sources (uses `withFormatDirs` from `phel-config.php`):
+
+```bash
+./vendor/bin/phel format
+```
+
+## Updating the Phel version
+
+`composer.json` currently pins a stable release:
+
+```json
+{
+    "require": {
+        "phel-lang/phel-lang": "^0.37"
+    }
+}
+```
+
+Pull the latest matching release:
+
+```bash
+composer update phel-lang/phel-lang
+```
+
+To track development HEAD instead, switch to `dev-main` and allow dev stability:
+
+```json
+{
+    "require": {
+        "phel-lang/phel-lang": "dev-main"
+    },
+    "minimum-stability": "dev",
+    "prefer-stable": true
+}
+```
+
+Pin to a specific commit (useful for bisecting upstream regressions):
+
+```bash
+composer require "phel-lang/phel-lang:dev-main#<commit-hash>"
+```
+
+## Reader conditionals
+
+The shared `.cljc` tests select the Phel branch via `:phel`:
+
+```clojure
+#?(:clj  (Integer/MAX_VALUE)
+   :cljs js/Number.MAX_SAFE_INTEGER
+   :phel php/PHP_INT_MAX)
+```
+
+Phel exposes PHP globals under the `php/` namespace and core types under `Phel.Lang.*`
+(e.g. `Phel.Lang.ExInfoException`, `Phel.Lang.Collections.Map.PersistentMapInterface`).
+See [writing-tests.md](writing-tests.md) for cross-dialect conventions.
diff --git a/doc/writing-tests.md b/doc/writing-tests.md
index 6e457479..7bf92d69 100644
--- a/doc/writing-tests.md
+++ b/doc/writing-tests.md
@@ -26,6 +26,7 @@ If possible, install them all and run the tests against each dialect before subm
 3. [Babashka](babashka.md)
 4. [Clojure CLR](clojureclr.md)
 5. [Basilisp](basilisp.md)
+6. [Phel](phel.md)
 
 ## How to Write a New Test
 
@@ -109,11 +110,12 @@ $ bb test-jvm        # run tests under Clojure JVM
 $ bb test-cljs       # run tests under ClojureScript on Node.js
 $ bb test-bb         # run tests under Babashka
 $ bb test-lpy        # run tests under Basilisp
+$ bb test-phel       # run tests under Phel
 ```
 
-Ideally, you should run all three of these *before* submitting a PR.
+Ideally, you should run all of these *before* submitting a PR.
 This helps prevent the PR from failing during CI testing.
-The Clojure Test Suite CI testing runs the tests in Clojure, ClojureScript, Babashka, and ClojureCLR environments.
+The Clojure Test Suite CI testing runs the tests in Clojure, ClojureScript, Babashka, ClojureCLR, Basilisp, and Phel environments.
 
 ### Create commits
 
diff --git a/phel-config.php b/phel-config.php
new file mode 100644
index 00000000..d4c97a06
--- /dev/null
+++ b/phel-config.php
@@ -0,0 +1,7 @@
+<?php
+// Reference: https://phel-lang.org/documentation/configuration/
+return Phel\Config\PhelConfig::forProject()
+    ->withSrcDirs([])
+    ->withTestDirs(['test'])
+    ->withFormatDirs(['test'])
+    ->withWarnDeprecations();
diff --git a/test/clojure/core_test/aclone.cljc b/test/clojure/core_test/aclone.cljc
index 48cd7fc2..9ef100d4 100644
--- a/test/clojure/core_test/aclone.cljc
+++ b/test/clojure/core_test/aclone.cljc
@@ -13,8 +13,12 @@
       (is (= 3 (alength a')))
       (is (every? identity (map #(= (aget a %) (aget a' %)) (range 3))))
       (is (zero? (alength b')))
-      (is (not (identical? a a')))
-      (is (not (identical? b b')))
+      ;; Phel PHP arrays are value types without reference-identity concept
+      ;; https://github.com/phel-lang/phel-lang/issues/1735
+      #?@(:phel []
+          :default
+          [(is (not (identical? a a')))
+           (is (not (identical? b b')))])
       (aset a 1 11)
       (is (= 11 (aget a 1)))
       (is (= 2 (aget a' 1)))
diff --git a/test/clojure/core_test/add_watch.cljc b/test/clojure/core_test/add_watch.cljc
index 073f9261..6e929f17 100644
--- a/test/clojure/core_test/add_watch.cljc
+++ b/test/clojure/core_test/add_watch.cljc
@@ -20,7 +20,8 @@
                                           (catch #?(:cljs :default
                                                     :clj clojure.lang.ExceptionInfo
                                                     :cljr clojure.lang.ExceptionInfo
-                                                    :lpy basilisp.lang.exception/ExceptionInfo) e
+                                                    :lpy basilisp.lang.exception/ExceptionInfo
+                                                    :phel Phel.Lang.ExInfoException) e
                                             (let [data (ex-data e)]
                                               (vswap! state conj data)))))]
                         (do-update a)
@@ -73,6 +74,7 @@
                          {:key :e :ref r :old 14 :new 15 :tester :err})))))
 
     #?@(:cljs []
+        :phel []
         :default
         [(def testvar-a 0)
          (def testvar-b 10)
@@ -145,6 +147,7 @@
 
     #?(:cljs nil
        :lpy nil
+       :phel nil
        :default
        (testing "watch ref"
          (let [state (volatile! [])
@@ -217,6 +220,7 @@
 
     #?@(:cljs []
         :lpy []
+        :phel []
         :default
         [(testing "watch agent"
            (let [state (volatile! [])
diff --git a/test/clojure/core_test/ancestors.cljc b/test/clojure/core_test/ancestors.cljc
index d644e5c8..9d30695c 100644
--- a/test/clojure/core_test/ancestors.cljc
+++ b/test/clojure/core_test/ancestors.cljc
@@ -5,8 +5,8 @@
 (when-var-exists ancestors
 
   ; Some classes for testing ancestors by type inheritance
-  (def AncestorT #?(:cljs js/Object :lpy python/object :default Object))
-  (def ChildT #?(:cljs :default :lpy basilisp.lang.set/PersistentSet :default clojure.lang.PersistentHashSet))
+  (def AncestorT #?(:cljs js/Object :lpy python/object :phel ArrayIterator :default Object))
+  (def ChildT #?(:cljs :default :lpy basilisp.lang.set/PersistentSet :phel RecursiveArrayIterator :default clojure.lang.PersistentHashSet))
 
   ; Some custom types for testing ancestors by type inheritance
   (defprotocol TestAncestorsProtocol)
@@ -73,14 +73,15 @@
 
       (testing "returns ancestors by type inheritance when tag is a class"
         #?(:cljs "cljs doesn't report ancestors by type inheritance yet (CLJS-3464)"
+           :phel (is (contains? (ancestors ChildT) AncestorT))
            :clj  (is (contains? (ancestors ChildT) AncestorT))))
 
       #?(:bb      "bb doesn't report ancestors by type inheritance for custom types"
          :cljs    "cljs doesn't report ancestors by type inheritance yet (CLJS-3464)"
          :default (testing "returns ancestors by type inheritance when tag is a custom type"
-                    (is (contains? (ancestors TestAncestorsType) #?(:lpy (:interface TestAncestorsProtocol) :default clojure.core_test.ancestors.TestAncestorsProtocol)))
-                    (is (contains? (ancestors TestAncestorsRecord) #?(:lpy (:interface TestAncestorsProtocol) :default clojure.core_test.ancestors.TestAncestorsProtocol)))
-                    (is (contains? (ancestors TestAncestorsRecord) #?(:lpy basilisp.lang.interfaces/IAssociative :default clojure.lang.Associative)))
+                    (is (contains? (ancestors TestAncestorsType) #?(:lpy (:interface TestAncestorsProtocol) :phel TestAncestorsProtocol :default clojure.core_test.ancestors.TestAncestorsProtocol)))
+                    (is (contains? (ancestors TestAncestorsRecord) #?(:lpy (:interface TestAncestorsProtocol) :phel TestAncestorsProtocol :default clojure.core_test.ancestors.TestAncestorsProtocol)))
+                    (is (contains? (ancestors TestAncestorsRecord) #?(:lpy basilisp.lang.interfaces/IAssociative :phel Phel.Lang.Collections.Map.PersistentMapInterface :default clojure.lang.Associative)))
                     (is (nil? (ancestors TestAncestorsProtocol)))))
 
       (testing "does not throw on invalid tag"
@@ -142,8 +143,8 @@
          :cljs    "cljs doesn't report ancestors by type inheritance yet (CLJS-3464)"
          :default (testing "returns ancestors by type inheritance when tag is a custom type, whether the tag is in h or not"
                     (are [h tag] (let [actual-ancestors (ancestors h tag)]
-                                   (and (contains? actual-ancestors #?(:lpy (:interface TestAncestorsProtocol) :default clojure.core_test.ancestors.TestAncestorsProtocol))
-                                        (contains? actual-ancestors #?(:lpy basilisp.lang.interfaces/IAssociative :default clojure.lang.Associative))))
+                                   (and (contains? actual-ancestors #?(:lpy (:interface TestAncestorsProtocol) :phel TestAncestorsProtocol :default clojure.core_test.ancestors.TestAncestorsProtocol))
+                                        (contains? actual-ancestors #?(:lpy basilisp.lang.interfaces/IAssociative :phel Phel.Lang.Collections.Map.PersistentMapInterface :default clojure.lang.Associative))))
                                  ; tag in h
                                  datatypes TestAncestorsRecord
                                  ; tag not in h
diff --git a/test/clojure/core_test/associative_qmark.cljc b/test/clojure/core_test/associative_qmark.cljc
index 3cd01f1f..fc15745e 100644
--- a/test/clojure/core_test/associative_qmark.cljc
+++ b/test/clojure/core_test/associative_qmark.cljc
@@ -19,8 +19,12 @@
       false #{}
       false #{:a :b}
       false "ab"
-      false (seq "ab")                  ; seq
-      false (to-array [1 2 3])
+
+      #?@(:phel [true (seq "ab") ; PHP arrays are associative
+                 true (to-array [1 2 3])]
+          :default
+          [false (seq "ab")                  ; seq
+           false (to-array [1 2 3])])
       false :a
       false 'a
       false 1
diff --git a/test/clojure/core_test/char_qmark.cljc b/test/clojure/core_test/char_qmark.cljc
index 999578d2..1b1ae558 100644
--- a/test/clojure/core_test/char_qmark.cljc
+++ b/test/clojure/core_test/char_qmark.cljc
@@ -44,6 +44,9 @@
           [true "0"
            true "1"]
           :lpy
+          [true "0"
+           true "1"]
+          :phel
           [true "0"
            true "1"]
           :default
diff --git a/test/clojure/core_test/dec.cljc b/test/clojure/core_test/dec.cljc
index 438c338f..669eda28 100644
--- a/test/clojure/core_test/dec.cljc
+++ b/test/clojure/core_test/dec.cljc
@@ -27,6 +27,7 @@
       #?(:clj (is (p/thrown? (dec Long/MIN_VALUE)))
          :cljr (is (p/thrown? (dec Int64/MinValue)))
          :cljs (is (= (dec js/Number.MIN_SAFE_INTEGER) (- js/Number.MIN_SAFE_INTEGER 2)))
+         :phel (is (= (dec php/PHP_INT_MIN) (dec php/PHP_INT_MIN)))
          :lpy []  ; Python integers cannot underflow
          :jank (is (p/thrown? (dec min-int)))
          :default (is false "TODO underflow")))
diff --git a/test/clojure/core_test/derive.cljc b/test/clojure/core_test/derive.cljc
index b39d2b54..a112204c 100644
--- a/test/clojure/core_test/derive.cljc
+++ b/test/clojure/core_test/derive.cljc
@@ -13,7 +13,7 @@
                           success)
                         ::rect ::shape
                         'n/a 'n/b
-                        #?(:cljs js/String :lpy python/str :default String) ::object))
+                        #?(:cljs js/String :lpy python/str :phel stdClass :default String) ::object))
 
     (testing "derive h tag parent"
       (are [expected h tag parent] (= expected (derive h tag parent))
@@ -32,9 +32,9 @@
                                     :descendants {'n/b #{'n/a}}
                                     :parents     {'n/a #{'n/b}}} (make-hierarchy) 'n/a 'n/b
 
-                                   {:ancestors   {#?(:cljs js/String :lpy python/str :default String) #{::object}}
-                                    :descendants {::object #{#?(:cljs js/String :lpy python/str :default String)}}
-                                    :parents     {#?(:cljs js/String :lpy python/str :default String) #{::object}}} (make-hierarchy) #?(:cljs js/String :lpy python/str :default String) ::object
+                                   {:ancestors   {#?(:cljs js/String :lpy python/str :phel stdClass :default String) #{::object}}
+                                    :descendants {::object #{#?(:cljs js/String :lpy python/str :phel stdClass :default String)}}
+                                    :parents     {#?(:cljs js/String :lpy python/str :phel stdClass :default String) #{::object}}} (make-hierarchy) #?(:cljs js/String :lpy python/str :phel stdClass :default String) ::object
 
                                    {:ancestors   {::rect #{::shape}, ::square #{::rect ::shape}}
                                     :descendants {::rect #{::square}, ::shape #{::rect ::square}}
@@ -74,11 +74,11 @@
                                       ::a :b
                                       'a 'b
                                       'n/a 'b
-                                      #?(:cljs js/String :lpy python/str :default String) :b)))
+                                      #?(:cljs js/String :lpy python/str :phel stdClass :default String) :b)))
 
       (testing "more invalid parents"
         (are [tag parent] (p/thrown? (derive tag parent))
-                          ::tag #?(:cljs js/String :lpy python/str :default String)
+                          ::tag #?(:cljs js/String :lpy python/str :phel stdClass :default String)
                           ::tag 42
                           ::tag "parent"))
 
diff --git a/test/clojure/core_test/double_qmark.cljc b/test/clojure/core_test/double_qmark.cljc
index 54252d9d..ad5a6281 100644
--- a/test/clojure/core_test/double_qmark.cljc
+++ b/test/clojure/core_test/double_qmark.cljc
@@ -32,6 +32,10 @@
               true (float 1.0)
               true (float -1.0)]
              :lpy
+             [true (float 0.0)
+              true (float 1.0)
+              true (float -1.0)]
+             :phel
              [true (float 0.0)
               true (float 1.0)
               true (float -1.0)]
diff --git a/test/clojure/core_test/eq.cljc b/test/clojure/core_test/eq.cljc
index dcde3ebb..3bbf3024 100644
--- a/test/clojure/core_test/eq.cljc
+++ b/test/clojure/core_test/eq.cljc
@@ -83,6 +83,7 @@
   (testing "regex"
     ;; Basilisp regex patterns compare equal and identical?
     #?(:lpy (is (eq #"my regex" #"my regex"))
+       :phel (is (eq #"my regex" #"my regex"))
        ;; Value-equal regex are NOT eq, only identical?
        :default (is (not (eq #"my regex" #"my regex"))))
     (is (let [r #"my regex"
diff --git a/test/clojure/core_test/float.cljc b/test/clojure/core_test/float.cljc
index 6b9696ba..a3a5a359 100644
--- a/test/clojure/core_test/float.cljc
+++ b/test/clojure/core_test/float.cljc
@@ -26,6 +26,7 @@
       ;; so float returns the same value here.
       #?@(:cljs [r/min-double r/min-double]
           :lpy [r/min-double r/min-double]
+          :phel [r/min-double r/min-double]
           :default [(float 0.0) r/min-double]))
     (is (NaN? (float ##NaN)))
 
diff --git a/test/clojure/core_test/inc.cljc b/test/clojure/core_test/inc.cljc
index cebc368e..6252cb79 100644
--- a/test/clojure/core_test/inc.cljc
+++ b/test/clojure/core_test/inc.cljc
@@ -28,6 +28,8 @@
       #?(:clj (is (p/thrown? (inc Long/MAX_VALUE)))
          :cljr (is (p/thrown? (inc Int64/MaxValue)))
          :cljs (is (= (inc js/Number.MAX_SAFE_INTEGER) (+ 2 js/Number.MAX_SAFE_INTEGER)))
+         ;; Phel integers avoid overflow by being promoted to BigInteger
+         :phel (is (not (= (inc php/PHP_INT_MAX) (+ 2 php/PHP_INT_MAX))))
          :lpy nil  ; Python integers cannot overflow
          :jank (is (p/thrown? (inc max-int)))
          :default (is false "overflow untested")))
diff --git a/test/clojure/core_test/int_qmark.cljc b/test/clojure/core_test/int_qmark.cljc
index dfd308da..435c14f5 100644
--- a/test/clojure/core_test/int_qmark.cljc
+++ b/test/clojure/core_test/int_qmark.cljc
@@ -4,50 +4,85 @@
             [clojure.core-test.portability #?(:cljs :refer-macros :default :refer) [when-var-exists]]))
 
 (when-var-exists int?
- (deftest test-int?
-   (are [expected x] (= expected (int? x))
-     true  0
-     true  1
-     true  -1
-     true  r/max-int
-     true  r/min-int
-     #?@(:cljs [true] :default [false]) 0.0
-     #?@(:cljs [true] :default [false]) 1.0
-     #?@(:cljs [true] :default [false]) -1.0
-     false 0.1
-     false 1.1
-     false -1.1
-     false r/max-double
-     false r/min-double
-     false ##Inf
-     false ##-Inf
-     false ##NaN
-     #?@(:cljs [true] :lpy [true] :default [false]) 0N
-     #?@(:cljs [true] :lpy [true] :default [false]) 1N
-     #?@(:cljs [true] :lpy [true] :default [false]) -1N
-     #?@(:cljs []
-         :default
-         [true  0/2
-          false 1/2
-          false -1/2])
-     #?@(:cljs [true] :default [false]) 0.0M
-     #?@(:cljs [true] :default [false]) 1.0M
-     #?@(:cljs [true] :default [false]) -1.0M
-     false nil
-     false true
-     false false
-     false "a string"
-     false "0"
-     false "1"
-     false "-1"
-     false {:a :map}
-     false #{:a-set}
-     false [:a :vector]
-     false '(:a :list)
-     false \0
-     false \1
-     false :a-keyword
-     false :0
-     false :1
-     false :-1
-     false 'a-sym)))
+  (deftest test-int?
+    (are [expected x] (= expected (int? x))
+      true  0
+      true  1
+      true  -1
+      true  r/max-int
+      true  r/min-int
+      false 0.1
+      false 1.1
+      false -1.1
+      false r/max-double
+      false r/min-double
+      false ##Inf
+      false ##-Inf
+      false ##NaN
+      false nil
+      false true
+      false false
+      false "a string"
+      false "0"
+      false "1"
+      false "-1"
+      false {:a :map}
+      false #{:a-set}
+      false [:a :vector]
+      false '(:a :list)
+      false \0
+      false \1
+      false :a-keyword
+      false :0
+      false :1
+      false :-1
+      false 'a-sym
+      #?@(:cljs
+          [true 0.0
+           true 1.0
+           true -1.0
+           true 0N
+           true 1N
+           true -1N
+           true 0.0M
+           true 1.0M
+           true -1.0M]
+          :lpy
+          [false 0.0
+           false 1.0
+           false -1.0
+           true 0N
+           true 1N
+           true -1N
+           false 0.0M
+           false 1.0M
+           false -1.0M
+           true 0/2
+           false 1/2
+           false -1/2]
+          :phel
+          [false 0.0
+           false 1.0
+           false -1.0
+           true 0N
+           true 1N
+           true -1N
+           false 0.0M
+           false 1.0M
+           false -1.0M
+           true 0/2
+           false 1/2
+           false -1/2]
+          :default
+          [false 0.0
+           false 1.0
+           false -1.0
+           false 0N
+           false 1N
+           false -1N
+           false 0.0M
+           false 1.0M
+           false -1.0M
+           true 0/2
+           false 1/2
+           false -1/2]))))
diff --git a/test/clojure/core_test/key.cljc b/test/clojure/core_test/key.cljc
index ce84fdee..2ce5f560 100644
--- a/test/clojure/core_test/key.cljc
+++ b/test/clojure/core_test/key.cljc
@@ -12,6 +12,7 @@
       ;; https://groups.google.com/g/clojure/c/FVcrbHJpCW4/m/Fh7NsX_Yb7sJ
       (is (= 'k (key #?(:cljs    (cljs.core/MapEntry. 'k 'v nil)
                         :lpy     (map-entry 'k 'v)
+                        :phel    (map-entry 'k 'v)
                         :default (clojure.lang.MapEntry/create 'k 'v)))))
       (when-var-exists sorted-map
         (is (= :a (key (first (sorted-map :a :b))))))
diff --git a/test/clojure/core_test/neg_int_qmark.cljc b/test/clojure/core_test/neg_int_qmark.cljc
index c3ca1ed9..37207c75 100644
--- a/test/clojure/core_test/neg_int_qmark.cljc
+++ b/test/clojure/core_test/neg_int_qmark.cljc
@@ -45,9 +45,21 @@
      #?@(:cljs [true -1.0
                 true -1.0M
                 true -1N]
+         :lpy [false -1.0
+               false -1.0M
+               true -1N
+               false 0/2
+               false 1/2
+               false -1/2]
+         :phel [false -1.0
+                false -1.0M
+                true -1N
+                false 0/2
+                false 1/2
+                false -1/2]
          :default [false -1.0
                    false -1.0M
-                   #?(:lpy true :default false) -1N
+                   false -1N
                    false 0/2
                    false 1/2
                    false -1/2]))))
diff --git a/test/clojure/core_test/number_range.cljc b/test/clojure/core_test/number_range.cljc
index 3caf2017..fb53dc12 100644
--- a/test/clojure/core_test/number_range.cljc
+++ b/test/clojure/core_test/number_range.cljc
@@ -5,12 +5,14 @@
 (def ^:const max-int #?(:clj Long/MAX_VALUE
                         :cljr Int64/MaxValue
                         :cljs js/Number.MAX_SAFE_INTEGER
+                        :phel php/PHP_INT_MAX
                         :jank (#cpp (:member (std.numeric_limits jank.i64) max))
                         :default 0x7FFFFFFFFFFFFFFF))
 
 (def ^:const min-int #?(:clj Long/MIN_VALUE
                         :cljr Int64/MinValue
                         :cljs js/Number.MIN_SAFE_INTEGER
+                        :phel php/PHP_INT_MIN
                         :jank (#cpp (:member (std.numeric_limits jank.i64) min))
                         :default -0x8000000000000000))
 
@@ -26,6 +28,7 @@
 (def ^:const max-double #?(:clj Double/MAX_VALUE
                            :cljr Double/MaxValue
                            :cljs js/Number.MAX_VALUE
+                           :phel php/PHP_FLOAT_MAX
                            :lpy (.-max sys/float-info)
                            :jank (#cpp (:member (std.numeric_limits jank.f64) max))
                            :default 1.7976931348623157e+308))
@@ -33,6 +36,7 @@
 (def ^:const min-double #?(:clj Double/MIN_VALUE
                            :cljr Double/Epsilon ; NOTE: definitely not Double/MinValue -- ouch!
                            :cljs js/Number.MIN_VALUE
+                           :phel php/PHP_FLOAT_MIN
                            :lpy (.-min sys/float_info)
                            :jank (#cpp (:member (std.numeric_limits jank.f64) min))
                            :default 4.9e-324))
diff --git a/test/clojure/core_test/parents.cljc b/test/clojure/core_test/parents.cljc
index 3d4f75db..fe3ddae6 100644
--- a/test/clojure/core_test/parents.cljc
+++ b/test/clojure/core_test/parents.cljc
@@ -67,6 +67,9 @@
          :lpy     (testing "returns parents by type inheritance when tag is a class"
                     (is (contains? (parents python/str) python/object))
                     (is (nil? (parents python/object))))
+         :phel    (testing "returns parents by type inheritance when tag is a class"
+                    (is (contains? (parents RuntimeException) Exception))
+                    (is (nil? (parents stdClass))))
          :default (testing "returns parents by type inheritance when tag is a class"
                     (is (contains? (parents String) Object))
                     (is (nil? (parents Object)))))
@@ -74,8 +77,8 @@
       #?(:bb      "bb doesn't report parents by type inheritance for custom types"
          :cljs    "cljs doesn't report parents by type inheritance yet (CLJS-3464)"
          :default (testing "returns parents by type inheritance when tag is a custom type"
-                    (is (contains? (parents TestParentsType) #?(:lpy (:interface TestParentsProtocol) :default clojure.core_test.parents.TestParentsProtocol)))
-                    (is (contains? (parents TestParentsRecord) #?(:lpy (:interface TestParentsProtocol) :default clojure.core_test.parents.TestParentsProtocol)))
+                    (is (contains? (parents TestParentsType) #?(:lpy (:interface TestParentsProtocol) :phel TestParentsProtocol :default clojure.core_test.parents.TestParentsProtocol)))
+                    (is (contains? (parents TestParentsRecord) #?(:lpy (:interface TestParentsProtocol) :phel TestParentsProtocol :default clojure.core_test.parents.TestParentsProtocol)))
                     (is (nil? (parents TestParentsProtocol)))))
 
       (testing "does not throw on invalid tag"
@@ -132,6 +135,13 @@
                                         ; tag not in h
                       diamond
                       datatypes))
+         :phel    (testing "returns parents by type inheritance when tag is a class, whether the tag is in h or not"
+                    (are [h] (contains? (parents h RuntimeException) Exception)
+                                        ; tag in h
+                      (derive (make-hierarchy) RuntimeException ::object)
+                                        ; tag not in h
+                      diamond
+                      datatypes))
          :default (testing "returns parents by type inheritance when tag is a class, whether the tag is in h or not"
                     (are [h] (contains? (parents h String) Object)
                              ; tag in h
@@ -143,7 +153,7 @@
       #?(:bb      "bb doesn't report parents by type inheritance for custom types"
          :cljs    "cljs doesn't report parents by type inheritance yet (CLJS-3464)"
          :default (testing "returns parents by type inheritance when tag is a custom type, whether the tag is in h or not"
-                    (are [h tag] (contains? (parents h tag) #?(:lpy (:interface TestParentsProtocol) :default clojure.core_test.parents.TestParentsProtocol))
+                    (are [h tag] (contains? (parents h tag) #?(:lpy (:interface TestParentsProtocol) :phel TestParentsProtocol :default clojure.core_test.parents.TestParentsProtocol))
                                  ; tag in h
                                  datatypes TestParentsType
                                  datatypes TestParentsRecord
diff --git a/test/clojure/core_test/portability.cljc b/test/clojure/core_test/portability.cljc
index 6b7a5256..faeb0571 100644
--- a/test/clojure/core_test/portability.cljc
+++ b/test/clojure/core_test/portability.cljc
@@ -18,6 +18,7 @@
   ;; return true if the fractional part of the double is zero
   #?(:cljs (integer? n)
      :lpy (integer? n)
+     :phel (integer? n)
      :jank (cpp/jank.runtime.is_big_integer n)
      :default
      (and (integer? n)
@@ -27,7 +28,8 @@
   (#?(:cljr System.Threading.Thread/Sleep
       :cljs #(js/setTimeout identity %)
       :clj Thread/sleep
-      :lpy time/sleep)
+      :lpy time/sleep
+      :phel #(phel.async/delay (/ % 1000)))
    ms))
 
 ;; --- Portable exception multimethod. ---
@@ -66,6 +68,7 @@
          (report-failure# failure-opts#)
          (catch #?(:jank ~'jank.runtime.object_ref
                    :clj ~'Throwable
+                   :phel ~'Throwable
                    :default ~'Exception) e#
            (report-success# (success-opts# e#))
            e#)
diff --git a/test/clojure/core_test/pos_int_qmark.cljc b/test/clojure/core_test/pos_int_qmark.cljc
index 15c303c4..415338d1 100644
--- a/test/clojure/core_test/pos_int_qmark.cljc
+++ b/test/clojure/core_test/pos_int_qmark.cljc
@@ -47,8 +47,20 @@
 
       #?@(:cljs [true 1.0
                  true 1.0M]
+          :lpy [false 1.0
+                true 1N
+                false 0/2
+                false 1/2
+                false -1/2
+                false 1.0M]
+          :phel [false 1.0
+                 true 1N
+                 false 0/2
+                 false 1/2
+                 false -1/2
+                 false 1.0M]
           :default [false 1.0
-                    #?(:lpy true :default false) 1N
+                    false 1N
                     false 0/2
                     false 1/2
                     false -1/2
diff --git a/test/clojure/core_test/print_str.cljc b/test/clojure/core_test/print_str.cljc
index ec5d16f6..0baa7af5 100644
--- a/test/clojure/core_test/print_str.cljc
+++ b/test/clojure/core_test/print_str.cljc
@@ -6,5 +6,6 @@
  (deftest test-print-str
    (is (= "a string" (print-str "a" "string")))
    (is (= #?(:cljs "nil a string A   1 17 [:a :b] {:c :d} #{:e}"
+             :phel "nil a string A   1 17 [:a :b] {:c :d} #{:e}"
              :default "nil a string A   1 17.0 [:a :b] {:c :d} #{:e}")
           (print-str nil "a" "string" \A \space 1 17.0 [:a :b] {:c :d} #{:e})))))
diff --git a/test/clojure/core_test/reduce.cljc b/test/clojure/core_test/reduce.cljc
index 5d70cc48..6a6471de 100644
--- a/test/clojure/core_test/reduce.cljc
+++ b/test/clojure/core_test/reduce.cljc
@@ -9,32 +9,38 @@
               (#?(:clj Integer.
                   :cljr identity
                   :cljs js/Number.
-                  :lpy python/int) x))
+                  :lpy python/int
+                  :phel php/intval) x))
 
    :Integer #?(:clj Integer/TYPE
                :cljr System.Int32
                :cljs js/Number
-               :lpy python/int)
+               :lpy python/int
+               :phel php/intval)
 
    :Long #?(:clj Long/TYPE
             :cljr System.Int64
             :cljs js/Number
-            :lpy python/int)
+            :lpy python/int
+            :phel php/intval)
 
    :Float #?(:clj Long/TYPE
              :cljr System.Single
              :cljs js/Number
-             :lpy python/float)
+             :lpy python/float
+             :phel php/floatval)
 
    :Double #?(:clj Double/TYPE
               :cljr System.Double
               :cljs js/Number
-              :lpy python/float)
+              :lpy python/float
+              :phel php/floatval)
 
    :Boolean #?(:clj Boolean/TYPE
                :cljr System.Boolean
                :cljs js/Boolean
-               :lpy python/bool)})
+               :lpy python/bool
+               :phel php/boolval)})
 
 
 (when-var-exists clojure.core/reduce
@@ -82,6 +88,7 @@
                   (reduce + arange)
                   (reduce + avec)
                   #?(:bb 4950
+                     :phel 4950
                      :clj (.reduce ^IReduce avec +))
                   (reduce + alist)
                   (reduce + obj-array)
diff --git a/test/clojure/core_test/remove_watch.cljc b/test/clojure/core_test/remove_watch.cljc
index 9c7bc816..f564c94a 100644
--- a/test/clojure/core_test/remove_watch.cljc
+++ b/test/clojure/core_test/remove_watch.cljc
@@ -103,6 +103,8 @@
        ;; Basilisp does not implement refs.
        :lpy
        nil
+       :phel
+       nil
 
        :default
        (testing "remove watch refs"
@@ -153,6 +155,8 @@
        ;; Basilisp does not implement agents.
        :lpy
        nil
+       :phel
+       nil
 
        :default
        (testing "remove watch agents"
diff --git a/test/clojure/core_test/repeat.cljc b/test/clojure/core_test/repeat.cljc
index 550b1c5e..cb7dfeaa 100644
--- a/test/clojure/core_test/repeat.cljc
+++ b/test/clojure/core_test/repeat.cljc
@@ -19,8 +19,10 @@
                           1 :a [:a]
                           3 :a [:a :a :a]
                           3.14 :a #?(:cljs    [:a :a :a :a]
+                                     :phel    [:a :a :a :a]
                                      :default [:a :a :a])
                           3.99 :a #?(:cljs    [:a :a :a :a]
+                                     :phel    [:a :a :a :a]
                                      :default [:a :a :a])
                           7 :a [:a :a :a :a :a :a :a]
                           7 nil [nil nil nil nil nil nil nil]))
diff --git a/test/clojure/core_test/seqable_qmark.cljc b/test/clojure/core_test/seqable_qmark.cljc
index 8c1db620..a543fa13 100644
--- a/test/clojure/core_test/seqable_qmark.cljc
+++ b/test/clojure/core_test/seqable_qmark.cljc
@@ -15,19 +15,29 @@
       true nil
       true "a string"
       true (object-array 3)
-
-      ;; Basilisp does not currently implement sorted collections or array-map.
-      #?@(:lpy []
-          :default [true (sorted-map :a 1)
-                    true (sorted-set :a)
-                    true (array-map :a 1)
-                    true (seq (sorted-map :a 1))
-                    true (seq (sorted-set :a))])
-
       false 1
       false 1N
       false 1.0
       false 1.0M
       false :a-keyword
       false 'a-sym
-      #?(:cljs true :lpy true :default false) \a)))
+      ;; Basilisp does not currently implement sorted collections or array-map.
+      #?@(:lpy [true \a]
+          :cljs [true \a
+                 true (sorted-map :a 1)
+                 true (sorted-set :a)
+                 true (array-map :a 1)
+                 true (seq (sorted-map :a 1))
+                 true (seq (sorted-set :a))]
+          :phel [true \a
+                 true (sorted-map :a 1)
+                 true (sorted-set :a)
+                 true (array-map :a 1)
+                 true (seq (sorted-map :a 1))
+                 true (seq (sorted-set :a))]
+          :default [false \a
+                    true (sorted-map :a 1)
+                    true (sorted-set :a)
+                    true (array-map :a 1)
+                    true (seq (sorted-map :a 1))
+                    true (seq (sorted-set :a))]))))
diff --git a/test/clojure/core_test/short.cljc b/test/clojure/core_test/short.cljc
index 695cc35d..0f7b1164 100644
--- a/test/clojure/core_test/short.cljc
+++ b/test/clojure/core_test/short.cljc
@@ -11,6 +11,7 @@
     (is (int? (short 0)))
     #?@(:cljs []
         :lpy [] ; Python VMs only have one integer type.
+        :phel []
         :default
         [(is (instance? #?(:clj java.lang.Short :cljr System.Int16) (short 0)))])
 
diff --git a/test/clojure/core_test/special_symbol_qmark.cljc b/test/clojure/core_test/special_symbol_qmark.cljc
index 8be82f30..4d4f5397 100644
--- a/test/clojure/core_test/special_symbol_qmark.cljc
+++ b/test/clojure/core_test/special_symbol_qmark.cljc
@@ -9,23 +9,27 @@
       (are [arg] (special-symbol? 'arg)
                  ;; Basilisp does not recognize these as special symbols.
                  #?@(:lpy []
+                     :phel [&]
                      :default [&
                                case*
                                new])
-                 .
+                 ;; Phel does not recognize these as special symbols.
+                 #?@(:phel []
+                     :default [.
+                               deftype*
+                               fn*
+                               let*
+                               letfn*
+                               loop*
+                               set!])
+
                  catch
                  def
-                 deftype*
                  do
                  finally
-                 fn*
                  if
-                 let*
-                 letfn*
-                 loop*
                  quote
                  recur
-                 set!
                  throw
                  try
                  var))
diff --git a/test/clojure/core_test/str.cljc b/test/clojure/core_test/str.cljc
index 9c218b11..90a75323 100644
--- a/test/clojure/core_test/str.cljc
+++ b/test/clojure/core_test/str.cljc
@@ -51,6 +51,10 @@
           ["0"          0.0M
            "1"          1.0M
            "-1"         -1.0M]
+          :phel
+          ["0.0"          0.0M
+           "1.0"          1.0M
+           "-1.0"         -1.0M]
           :default
           ["0"          0/2
            "1/2"        1/2
diff --git a/test/clojure/core_test/string_qmark.cljc b/test/clojure/core_test/string_qmark.cljc
index 8eb14745..a5c66327 100644
--- a/test/clojure/core_test/string_qmark.cljc
+++ b/test/clojure/core_test/string_qmark.cljc
@@ -10,6 +10,8 @@
       true "0"
       true "1"
       true "-1"
+      ; Phel/PHP lacks class type and classes are represented as strings
+      #?@(:phel [true stdClass])
 
       false 0
       false 1
@@ -55,6 +57,11 @@
            true \A
            true \space]
           :lpy
+          [true \0
+           true \1
+           true \A
+           true \space]
+          :phel
           [true \0
            true \1
            true \A
diff --git a/test/clojure/core_test/symbol.cljc b/test/clojure/core_test/symbol.cljc
index 0c5ea5d3..63826a8f 100644
--- a/test/clojure/core_test/symbol.cljc
+++ b/test/clojure/core_test/symbol.cljc
@@ -48,6 +48,7 @@
       'abc*+!-_'?<>= "abc*+!-_'?<>="
       #?(:cljs 'cljs.core/+
          :lpy 'basilisp.core/+
+         :phel 'phel.core/+
          :default 'clojure.core/+) #'+)
 
     (are [expected ns name] (= expected (symbol ns name))
diff --git a/test/clojure/core_test/taps.cljc b/test/clojure/core_test/taps.cljc
index 9c456719..7f02e6aa 100644
--- a/test/clojure/core_test/taps.cljc
+++ b/test/clojure/core_test/taps.cljc
@@ -66,7 +66,7 @@
        (defn tap-tester
          [atom-ref]
          (fn [x]
-           (if (instance? #?(:lpy basilisp.lang.interfaces/IPending :default clojure.lang.IPending) x)
+           (if (instance? #?(:lpy basilisp.lang.interfaces/IPending :phel Phel.Fiber.Domain.Awaitable :default clojure.lang.IPending) x)
              (deliver x nil)
              (swap! atom-ref conj x))))
 
diff --git a/test/clojure/core_test/val.cljc b/test/clojure/core_test/val.cljc
index bf2ada33..455bc0ba 100644
--- a/test/clojure/core_test/val.cljc
+++ b/test/clojure/core_test/val.cljc
@@ -11,6 +11,7 @@
       ;; https://groups.google.com/g/clojure/c/FVcrbHJpCW4/m/Fh7NsX_Yb7sJ
       (is (= 'v (val #?(:cljs    (cljs.core/MapEntry. 'k 'v nil)
                         :lpy     (map-entry 'k 'v)
+                        :phel    (map-entry 'k 'v)
                         :default (clojure.lang.MapEntry/create 'k 'v)))))
       (is (= :b (val (first (hash-map :a :b)))))
       (when-var-exists sorted-map
diff --git a/test/clojure/core_test/vec.cljc b/test/clojure/core_test/vec.cljc
index 9b288f5b..da2d12c1 100644
--- a/test/clojure/core_test/vec.cljc
+++ b/test/clojure/core_test/vec.cljc
@@ -25,6 +25,7 @@
 
     #?(:cljr    "cljr does not alias array"
        :lpy     "Basilisp does not alias array"
+       :phel    "Phel does not alias array"
        :default (testing "array aliasing"
                   (let [arr (to-array [1 2 3]), v (vec arr)]
                     (is (= [1 2 3] v))