diff --git a/.gitignore b/.gitignore
index c13c3e2..21c9d6e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ __pycache__
 .*_cache
 .pre-commit-config.yaml
 .vscode
+.coverage
diff --git a/README.md b/README.md
index 43738b1..fe24133 100644
--- a/README.md
+++ b/README.md
@@ -26,5 +26,7 @@ total | 1
 
 ## todo
 
-- [ ] roll with (dis)advantage
+- [x] roll with (dis)advantage
 - [ ] interactive rolling mode
+- [x] print criticals
+- [ ] use property testing
diff --git a/flake.lock b/flake.lock
index 1bf6d71..2d442de 100644
--- a/flake.lock
+++ b/flake.lock
@@ -74,11 +74,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1691579266,
-        "narHash": "sha256-Ue2iaxU5VxwjXX6bWv/ElOl35O4+Rk630jBjMqQDRRs=",
+        "lastModified": 1691931346,
+        "narHash": "sha256-QLK0wLyJEnLU37CTBNnZBY6mNily7w8zeb34XyhSGh0=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "a14013769370b021e23200e7199d8cfaeb97098a",
+        "rev": "8f38b58c34bb759ae83a0581120fe2d7fa6bb539",
         "type": "github"
       },
       "original": {
@@ -133,11 +133,11 @@
         "nixpkgs-stable": "nixpkgs-stable"
       },
       "locked": {
-        "lastModified": 1691397944,
-        "narHash": "sha256-4fa4bX3kPYKpEssgrFRxRCPVXczidArDeSWaUMSzQAU=",
+        "lastModified": 1691747570,
+        "narHash": "sha256-J3fnIwJtHVQ0tK2JMBv4oAmII+1mCdXdpeCxtIsrL2A=",
         "owner": "cachix",
         "repo": "pre-commit-hooks.nix",
-        "rev": "e5588ddffd4c3578547a86ef40ec9a6fbdae2986",
+        "rev": "c5ac3aa3324bd8aebe8622a3fc92eeb3975d317a",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index cb38573..d07b199 100644
--- a/flake.nix
+++ b/flake.nix
@@ -26,9 +26,10 @@
           pre-commit.settings.hooks = {
             autoflake.enable = true;
             black.enable = true;
+            mypy.enable = true;
             ruff.enable = true;
-            pyright.enable = true;
           };
+          pre-commit.settings.settings.mypy.binPath = "${pkgs.python311Packages.mypy}/bin/mypy";
           packages.default = package;
           devShells.default = pkgs.mkShell {
             shellHook = ''
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..2be7b3f
--- /dev/null
+++ b/justfile
@@ -0,0 +1,30 @@
+build:
+    hatch build
+
+typing:
+    hatch run typing:check
+
+lint:
+    hatch run lint:check
+
+fmt:
+    hatch run lint:fmt
+
+# run all checks
+test: typing lint
+    hatch run check
+
+# create hatch envs
+env:
+    #!/usr/bin/env fish
+    for env in (hatch env show --json | jq 'keys[]' --raw-output)
+        hatch env create $env
+    end
+
+clean:
+    hatch clean
+    hatch env purge
+    rm -r .{mypy,pytest,ruff}_cache
+    rm -r dist
+    rm .coverage
+    fd __pycache__ --no-ignore --exec rm -r
diff --git a/pyproject.toml b/pyproject.toml
index b257eae..254c9c5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -30,7 +30,7 @@ Issues = "https://git.mat.services/mat/roll/issues"
 Source = "https://git.mat.services/mat/roll"
 
 [project.scripts]
-roll = "roll.cli:roll"
+roll = "roll.cli:cli"
 
 [tool.hatch.version]
 path = "roll/__about__.py"
@@ -47,7 +47,7 @@ cov-report = [
   "- coverage combine",
   "coverage report",
 ]
-cov = [
+check = [
   "test-cov",
   "cov-report",
 ]
@@ -55,15 +55,18 @@ cov = [
 [[tool.hatch.envs.all.matrix]]
 python = ["3.11"]
 
+[tool.hatch.envs.typing]
+extra-dependencies = ["mypy"]
+[tool.hatch.envs.typing.scripts]
+check = "mypy --install-types {args:roll tests}"
+
 [tool.hatch.envs.lint]
 detached = true
 dependencies = [
   "black>=23.1.0",
-  "pyright>=1.1.319",
   "ruff>=0.0.243",
 ]
 [tool.hatch.envs.lint.scripts]
-typing = "pyright --project pyproject.toml {args:roll tests}"
 style = [
   "ruff {args:.}",
   "black --check --diff {args:.}",
@@ -73,19 +76,18 @@ fmt = [
   "ruff --fix {args:.}",
   "style",
 ]
-all = [
+check = [
   "style",
-  "typing",
 ]
 
 [tool.black]
 target-version = ["py311"]
-line-length = 120
-skip-string-normalization = true
+line-length = 100
+# skip-string-normalization = true
 
 [tool.ruff]
 target-version = "py311"
-line-length = 120
+line-length = 100
 select = [
   "A",
   "ARG",
@@ -153,8 +155,21 @@ roll = ["roll", "*/roll/roll"]
 tests = ["tests", "*/roll/tests"]
 
 [tool.coverage.report]
+show_missing = true
+skip_empty = true
+fail_under = 100
 exclude_lines = [
   "no cov",
   "if __name__ == .__main__.:",
   "if TYPE_CHECKING:",
 ]
+
+[tool.mypy]
+pretty = true
+strict = true
+
+[[tool.mypy.overrides]]
+module = "tests.*"
+allow_untyped_defs = true
+allow_incomplete_defs = true
+check_untyped_defs = true
diff --git a/roll/__main__.py b/roll/__main__.py
index 2baf08e..b310620 100644
--- a/roll/__main__.py
+++ b/roll/__main__.py
@@ -1,6 +1,6 @@
-import sys
-
 if __name__ == "__main__":
-    from roll.cli import roll
+    import sys
 
-    sys.exit(roll())
+    from roll.cli import cli
+
+    sys.exit(cli())