diff --git a/colorless.cabal b/colorless.cabal
--- a/colorless.cabal
+++ b/colorless.cabal
@@ -3,7 +3,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           colorless
-version:        2.2.12
+version:        2.2.13
 synopsis:       Colorless
 description:    Colorless
 category:       Web
diff --git a/library/Colorless/Ast.hs b/library/Colorless/Ast.hs
--- a/library/Colorless/Ast.hs
+++ b/library/Colorless/Ast.hs
@@ -9,7 +9,7 @@
   , Lambda(..)
   , List(..)
   , Tuple(..)
-  , Begin(..)
+  , Do(..)
   , FnCall(..)
   , Enumeral(..)
   , Struct(..)
@@ -43,7 +43,7 @@
   | Ast'Lambda Lambda
   | Ast'List List
   | Ast'Tuple Tuple
-  | Ast'Begin Begin
+  | Ast'Do Do
   | Ast'FnCall FnCall
   | Ast'WrapCall WrapCall
   | Ast'StructCall StructCall
@@ -250,7 +250,7 @@
     <|> (Ast'Lambda <$> parseJSON v)
     <|> (Ast'List <$> parseJSON v)
     <|> (Ast'Tuple <$> parseJSON v)
-    <|> (Ast'Begin <$> parseJSON v)
+    <|> (Ast'Do <$> parseJSON v)
     <|> (Ast'FnCall <$> parseJSON v)
     <|> (Ast'EnumerationCall <$> parseJSON v)
     <|> (Ast'WrapCall <$> parseJSON v)
@@ -269,7 +269,7 @@
     Ast'Lambda a -> toJSON a
     Ast'List a -> toJSON a
     Ast'Tuple a -> toJSON a
-    Ast'Begin a -> toJSON a
+    Ast'Do a -> toJSON a
     Ast'FnCall a -> toJSON a
     Ast'EnumerationCall a -> toJSON a
     Ast'WrapCall a -> toJSON a
@@ -380,18 +380,18 @@
 instance ToJSON Tuple where
   toJSON Tuple{tuple} = toJSON $ "tuple" : map toJSON tuple
 
-data Begin = Begin
+data Do = Do
   { vals :: [Ast]
   } deriving (Show, Eq)
 
-instance FromJSON Begin where
+instance FromJSON Do where
   parseJSON (Array arr) = case V.toList arr of
-    "begin":xs -> Begin <$> mapM parseJSON xs
+    "do":xs -> Do <$> mapM parseJSON xs
     _ -> mzero
   parseJSON _ = mzero
 
-instance ToJSON Begin where
-  toJSON Begin{vals} = toJSON $ "begin" : map toJSON vals
+instance ToJSON Do where
+  toJSON Do{vals} = toJSON $ "do" : map toJSON vals
 
 data FnCall = FnCall
   { fn :: Ast
diff --git a/library/Colorless/Client/Expr.hs b/library/Colorless/Client/Expr.hs
--- a/library/Colorless/Client/Expr.hs
+++ b/library/Colorless/Client/Expr.hs
@@ -12,7 +12,7 @@
   , (<:>)
   , (<:)
   --
-  , begin
+  , dO
   , def
   , defn
   , defnRec
@@ -276,8 +276,8 @@
 stmt :: HasType a => Expr a -> Stmt (Expr a)
 stmt expr = Stmt [toAst expr] expr
 
-begin :: HasType a => Stmt (Expr a) -> Expr a
-begin (Stmt s _) = Expr (Ast'Begin $ Ast.Begin s)
+dO :: HasType a => Stmt (Expr a) -> Expr a
+dO (Stmt s _) = Expr (Ast'Do $ Ast.Do s)
 
 --
 
diff --git a/library/Colorless/Server/Expr.hs b/library/Colorless/Server/Expr.hs
--- a/library/Colorless/Server/Expr.hs
+++ b/library/Colorless/Server/Expr.hs
@@ -13,7 +13,7 @@
   , Lambda(..)
   , Fn(..)
   , List(..)
-  , Begin(..)
+  , Do(..)
   , FnCall(..)
   , ApiUnCall(..)
   , HollowUnCall(..)
@@ -94,7 +94,7 @@
   | Expr'Tuple (Tuple m)
   | Expr'Fn (Fn m)
   | Expr'FnCall (FnCall m)
-  | Expr'Begin (Begin m)
+  | Expr'Do (Do m)
   | Expr'ApiUnCall (ApiUnCall m)
   deriving (Show, Eq)
 
@@ -159,7 +159,7 @@
   { tuple :: [Expr m]
   } deriving (Show, Eq)
 
-data Begin m = Begin
+data Do m = Do
   { exprs :: [Expr m]
   } deriving (Show, Eq)
 
@@ -219,7 +219,7 @@
   Ast'Lambda Ast.Lambda{args,expr} -> Expr'Lambda $ Lambda args (fromAst expr)
   Ast'List Ast.List{list} -> Expr'List $ List $ map fromAst list
   Ast'Tuple Ast.Tuple{tuple} -> Expr'Tuple $ Tuple $ map fromAst tuple
-  Ast'Begin Ast.Begin{vals} -> Expr'Begin $ Begin $ map fromAst vals
+  Ast'Do Ast.Do{vals} -> Expr'Do $ Do $ map fromAst vals
   Ast'FnCall Ast.FnCall{fn,args} -> Expr'FnCall $ FnCall (fromAst fn) (map fromAst args)
   Ast'WrapCall Ast.WrapCall{n,w} -> Expr'ApiUnCall $ ApiUnCall'WrapUnCall $ WrapUnCall n (fromAst w)
   Ast'HollowCall Ast.HollowCall{n} -> Expr'ApiUnCall $ ApiUnCall'HollowUnCall $ HollowUnCall n
@@ -269,7 +269,7 @@
   Expr'List list -> evalList list envRef
   Expr'Tuple tuple -> evalTuple tuple envRef
   Expr'FnCall call -> evalFnCall call envRef
-  Expr'Begin begin -> evalBegin begin envRef
+  Expr'Do dO -> evalDo dO envRef
   Expr'ApiUnCall apiUnCall -> evalApiUnCall apiUnCall envRef
 
 forceVal :: (RuntimeThrower m) => Expr m -> Eval m Val
@@ -374,8 +374,8 @@
   tuple' <- mapM (\item -> eval item envRef) tuple
   return . Expr'Tuple $ Tuple tuple'
 
-evalBegin :: (MonadIO m, RuntimeThrower m) => Begin m -> IORef (Env m) -> Eval m (Expr m)
-evalBegin Begin{exprs} envRef = case exprs of
+evalDo :: (MonadIO m, RuntimeThrower m) => Do m -> IORef (Env m) -> Eval m (Expr m)
+evalDo Do{exprs} envRef = case exprs of
   [] -> return $ Expr'Val $ Val'Const $ Const'Null
   _ -> last <$> mapM (\expr -> eval expr envRef) exprs
 
diff --git a/package.yaml b/package.yaml
--- a/package.yaml
+++ b/package.yaml
@@ -1,5 +1,5 @@
 name: colorless
-version: '2.2.12'
+version: '2.2.13'
 category: Web
 synopsis: Colorless
 description: Colorless
diff --git a/tests/AstSpec.hs b/tests/AstSpec.hs
--- a/tests/AstSpec.hs
+++ b/tests/AstSpec.hs
@@ -78,10 +78,10 @@
         (parseAst $ toJSON [ "tuple", String "hello", String "world" ])
         (Just $ Ast'Tuple $ Tuple [Ast'Const $ Const'String "hello", Ast'Const $ Const'String "world"])
 
-    context "Begin" $ do
+    context "Do" $ do
       it "simple" $ shouldBe
-        (parseAst $ Array $ V.fromList ["begin", Bool True])
-        (Just $ Ast'Begin $ Begin [Ast'Const $ Const'Bool True])
+        (parseAst $ Array $ V.fromList ["do", Bool True])
+        (Just $ Ast'Do $ Do [Ast'Const $ Const'Bool True])
 
     context "FnCall" $ do
       it "simple" $ shouldBe
diff --git a/tests/ClientSpec.hs b/tests/ClientSpec.hs
--- a/tests/ClientSpec.hs
+++ b/tests/ClientSpec.hs
@@ -6,7 +6,7 @@
 import Colorless.Client
 
 _helloWorld :: Expr (Int32, Int32)
-_helloWorld = begin $ do
+_helloWorld = dO $ do
   x <- def "x" (i32 0)
   f <- defn "f" (fn2 "a" "b" add)
   stmt $ tuple2 x (f -< (x, i32 10))