diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e9ef7c0..330b79c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -35,7 +35,10 @@ jobs:
       - name: Poetry Config
         run: poetry config virtualenvs.in-project true
 
-      - uses: actions/cache@v2
+      - name: Install system dependencies
+        run: sudo apt-get update && sudo apt-get install -y libjpeg-dev zlib1g-dev
+
+      - uses: actions/cache@v4
         with:
           path: .venv
           key: poetry-${{ hashFiles('**/poetry.lock') }}
@@ -50,3 +53,6 @@ jobs:
 
       - name: Type-check (as warnings only)
         run: poetry run python -m mypy . || true
+
+      - name: Run tests
+        run: poetry run pytest -q
diff --git a/bot/bot_client.py b/bot/bot_client.py
index 1976e05..ef21d54 100644
--- a/bot/bot_client.py
+++ b/bot/bot_client.py
@@ -251,6 +251,12 @@ async def load_all_extensions(self):
 
         self.disabled_commands()
 
+        try:
+            synced = await self.tree.sync()
+            print(f"- Synced {len(synced)} application command(s).")
+        except Exception as e:
+            print(f"Failed to sync application commands: {e}")
+
         return errored
 
     async def reload_all_extensions(self):
diff --git a/bot/cogs/amigosecreto.py b/bot/cogs/amigosecreto.py
index c6aa423..b98c4ae 100644
--- a/bot/cogs/amigosecreto.py
+++ b/bot/cogs/amigosecreto.py
@@ -170,11 +170,17 @@ async def roll_amigo_secreto(self, ctx: Context):
 
         not_receiving = AmigoSecretoPerson.objects.filter(receiving=False).count()
 
-        if not_receiving > 0:
-            await ctx.author.send(f'Erro ao montar Amigo Secreto. Pessoas sem receber: {not_receiving}. Contate NRiver.')
-            return
-
-        await ctx.author.send(f'Amigo Secreto montado com sucesso. Total de pessoas: {AmigoSecretoPerson.objects.count()}')
+        if not_receiving > 0:
+            await ctx.author.send(
+                f"Erro ao montar Amigo Secreto. Pessoas sem receber: {not_receiving}. "
+                "Contate NRiver."
+            )
+            return
+
+        await ctx.author.send(
+            "Amigo Secreto montado com sucesso. Total de pessoas: "
+            f"{AmigoSecretoPerson.objects.count()}"
+        )
 
     @commands.check(is_pedim_or_nriver)
     @commands.command()
@@ -205,9 +211,10 @@ async def activate_amigo_secreto(self, ctx: Context):
         start_date_brt = await ctx.prompt(
             "Digite a data de inicio do Amigo Secreto (exemplo '20/12/2025 20:00'):"
         )
-        end_date_brt = await ctx.prompt(
-            "Digite a data de fim do Amigo Secreto (exemplo '30/12/2025 20:00'). A data do sorteio será 2 dias antes da data final informada:"
-        )
+        end_date_brt = await ctx.prompt(
+            "Digite a data de fim do Amigo Secreto (exemplo '30/12/2025 20:00'). "
+            "A data do sorteio será 2 dias antes da data final informada:"
+        )
 
         start_date_utc = datetime.strptime(start_date_brt, "%d/%m/%Y %H:%M") - timedelta(hours=3)
         end_date_utc = datetime.strptime(end_date_brt, "%d/%m/%Y %H:%M") - timedelta(hours=3)
@@ -237,7 +244,10 @@ async def delete_amigo_secreto(self, ctx: Context):
         if not confirmation:
             return await ctx.send("Comando cancelado")
 
-        return await ctx.send(f"Todas as inscrições do Amigo Secreto do Atlantis foram deletadas. Total de pessoas inscritas: {total_count}")
+        return await ctx.send(
+            "Todas as inscrições do Amigo Secreto do Atlantis foram deletadas. "
+            f"Total de pessoas inscritas: {total_count}"
+        )
 
     @commands.check(is_authenticated)
     @commands.command(aliases=["amigosecreto", "amigo"])
diff --git a/bot/cogs/chat.py b/bot/cogs/chat.py
index dabd79f..4b7c4bc 100644
--- a/bot/cogs/chat.py
+++ b/bot/cogs/chat.py
@@ -314,12 +314,14 @@ async def github(self, ctx: Context):
         github_embed.set_thumbnail(url=github_icon)
         return await ctx.send(content=None, embed=github_embed)
 
-    # @commands.bot_has_permissions(embed_links=True)
-    @commands.command(aliases=["atlbot", "atlbotcommands"])
-    async def atlcommands(self, ctx: Context):
-        runepixels_url = (
-            f"https://runepixels.com/clans/{self.bot.setting.clan_name}/about"
-        )
+    # @commands.bot_has_permissions(embed_links=True)
+    @commands.hybrid_command(
+        name="atlantisbot", aliases=["atlbot", "atlbotcommands", "atlcommands"]
+    )
+    async def atlantisbot(self, ctx: Context):
+        runepixels_url = (
+            f"https://runepixels.com/clans/{self.bot.setting.clan_name}/about"
+        )
         clan_banner = f"http://services.runescape.com/m=avatar-rs/l=3/a=869/{self.bot.setting.clan_name}/clanmotif.png"
         embed_title = "RunePixels"
 
diff --git a/poetry.lock b/poetry.lock
index a784764..95a66ca 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -536,6 +536,15 @@ files = [
 django = ">=2.2"
 pytz = "*"
 
+[[package]]
+name = "exceptiongroup"
+version = "1.1.3"
+description = "Backport of PEP 654 (exception groups)"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+files = []
+
 [[package]]
 name = "feedparser"
 version = "6.0.10"
@@ -684,6 +693,15 @@ files = [
     {file = "idna-3.4.tar.gz", hash = "sha256:814f528e8dead7d329833b91c5faa87d60bf71824cd12a7530b5526063d02cb4"},
 ]
 
+[[package]]
+name = "iniconfig"
+version = "2.0.0"
+description = "brain-dead simple config-ini parsing"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+files = []
+
 [[package]]
 name = "kiwisolver"
 version = "1.4.4"
@@ -1294,6 +1312,15 @@ files = [
 docs = ["furo (>=2023.3.27)", "proselint (>=0.13)", "sphinx (>=6.1.3)", "sphinx-autodoc-typehints (>=1.23,!=1.23.4)"]
 test = ["appdirs (==1.4.4)", "covdefaults (>=2.3)", "pytest (>=7.3.1)", "pytest-cov (>=4)", "pytest-mock (>=3.10)"]
 
+[[package]]
+name = "pluggy"
+version = "1.2.0"
+description = "plugin and hook calling mechanisms for python"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+files = []
+
 [[package]]
 name = "poetry-version"
 version = "0.1.5"
@@ -1443,6 +1470,22 @@ future = "*"
 requests = "*"
 requests-oauthlib = "*"
 
+[[package]]
+name = "pytest"
+version = "7.4.0"
+description = "pytest: simple powerful testing with Python"
+category = "dev"
+optional = false
+python-versions = ">=3.7"
+files = []
+
+[package.dependencies]
+exceptiongroup = {version = ">=1.0.0rc8", markers = "python_version < \"3.11\""}
+iniconfig = "*"
+packaging = "*"
+pluggy = ">=0.12,<2.0"
+tomli = {version = ">=1.0.0", markers = "python_version < \"3.11\""}
+
 [[package]]
 name = "pytz"
 version = "2023.3"
@@ -1788,4 +1831,4 @@ multidict = ">=4.0"
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.10"
-content-hash = "c435dccc3470036d500ae157664ed6444401f1d77cd52734bd72671b27374750"
+content-hash = "848379345137931d2d32cb2da98ad1e430d2c2d3b455d15a4af4b5242f7e6df8"
diff --git a/pyproject.toml b/pyproject.toml
index b40d47f..cebdeef 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -31,6 +31,7 @@ ruff = "^0.0.265"
 mypy = "^1.2.0"
 mypy_extensions = "^1.0.0"
 black = "^23.3.0"
+pytest = "^7.4.0"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..7ed37ac
--- /dev/null
+++ b/tests/__init__.py
@@ -0,0 +1 @@
+"""Test package for AtlantisBot."""
diff --git a/tests/helpers.py b/tests/helpers.py
new file mode 100644
index 0000000..71ca65d
--- /dev/null
+++ b/tests/helpers.py
@@ -0,0 +1,105 @@
+from __future__ import annotations
+
+import sys
+import types
+from dataclasses import dataclass
+from pathlib import Path
+from types import SimpleNamespace
+from typing import Any
+
+
+ROOT = Path(__file__).resolve().parents[1]
+if str(ROOT) not in sys.path:
+    sys.path.append(str(ROOT))
+
+
+def _stub_modules():
+    stub_rs3clans = types.ModuleType("rs3clans")
+    stub_rs3clans.Clan = object
+    stub_rs3clans.Player = object
+    sys.modules["rs3clans"] = stub_rs3clans
+
+    stub_bot_client = types.ModuleType("bot.bot_client")
+
+    class Bot:
+        pass
+
+    stub_bot_client.Bot = Bot
+    sys.modules["bot.bot_client"] = stub_bot_client
+
+    stub_tools = types.ModuleType("bot.utils.tools")
+    stub_tools.right_arrow = "->"
+
+    def has_any_role(*_args, **_kwargs):
+        return False
+
+    stub_tools.has_any_role = has_any_role
+    sys.modules["bot.utils.tools"] = stub_tools
+
+    stub_checks = types.ModuleType("bot.utils.checks")
+
+    async def is_authenticated(ctx):
+        return True
+
+    async def is_admin(ctx):
+        return True
+
+    stub_checks.is_authenticated = is_authenticated
+    stub_checks.is_admin = is_admin
+    sys.modules["bot.utils.checks"] = stub_checks
+
+    stub_context = types.ModuleType("bot.utils.context")
+
+    class Context:
+        pass
+
+    stub_context.Context = Context
+    sys.modules["bot.utils.context"] = stub_context
+
+    stub_raids = types.ModuleType("bot.cogs.raids")
+
+    async def time_till_raids():
+        return 0, 0, 0
+
+    stub_raids.time_till_raids = time_till_raids
+    sys.modules["bot.cogs.raids"] = stub_raids
+
+
+@dataclass
+class FakeSettings:
+    clan_name: str = "Atlantis"
+    banner_image: str = "https://example.com/banner.png"
+    prefix: str = "!"
+    role: dict[str, int] | None = None
+    chat: dict[str, int] | None = None
+
+    def __post_init__(self):
+        if self.role is None:
+            self.role = {"pvm_teacher": 123, "aod": 456, "aod_learner": 789}
+        if self.chat is None:
+            self.chat = {"aod": 321}
+
+
+class FakeContext:
+    def __init__(self):
+        self.sent_embed = None
+        self.sent_content = None
+        self.author = SimpleNamespace(roles=[])
+
+    async def send(self, content=None, *, embed=None):
+        self.sent_embed = embed
+        self.sent_content = content
+
+
+def make_chat():
+    _stub_modules()
+    from bot.cogs.chat import Chat  # noqa: E402
+
+    fake_bot = SimpleNamespace(setting=FakeSettings())
+    return Chat(fake_bot)
+
+
+def run_async(coro: Any):
+    import asyncio
+
+    return asyncio.run(coro)
diff --git a/tests/test_aplicar_aod_command.py b/tests/test_aplicar_aod_command.py
new file mode 100644
index 0000000..aff9c91
--- /dev/null
+++ b/tests/test_aplicar_aod_command.py
@@ -0,0 +1,12 @@
+from tests.helpers import FakeContext, make_chat, run_async
+
+
+def test_aplicar_aod_sends_text_message():
+    chat = make_chat()
+    ctx = FakeContext()
+
+    run_async(chat.aplicar_aod.callback(chat, ctx))
+
+    assert ctx.sent_embed is None
+    assert ctx.sent_content is not None
+    assert "Você aplicou para receber a tag de AoD" in ctx.sent_content
diff --git a/tests/test_atlantisbot_command.py b/tests/test_atlantisbot_command.py
new file mode 100644
index 0000000..54758fc
--- /dev/null
+++ b/tests/test_atlantisbot_command.py
@@ -0,0 +1,20 @@
+from discord.ext import commands
+
+from tests.helpers import FakeContext, make_chat, run_async
+
+
+def test_atlantisbot_is_hybrid_command():
+    chat = make_chat()
+    ctx = FakeContext()
+
+    command = chat.atlantisbot
+    assert isinstance(command, commands.HybridCommand)
+    assert command.name == "atlantisbot"
+    assert "atlbot" in command.aliases
+
+    run_async(command.callback(chat, ctx))
+
+    assert ctx.sent_content is None
+    assert ctx.sent_embed is not None
+    assert ctx.sent_embed.title == "RunePixels"
+    assert any(field.name.startswith("!claninfo") for field in ctx.sent_embed.fields)