6 files changed, 11 insertions, 3 deletions
diff --git a/src/Language/GraphQL/AST.hs b/src/Language/GraphQL/AST.hs
index 8f40c10..0c0ed89 100644
--- a/src/Language/GraphQL/AST.hs
+++ b/src/Language/GraphQL/AST.hs
@@ -68,6 +68,7 @@ data OperationType = Query | Mutation deriving (Eq, Show)
 -- | "Top-level" selection, selection on a operation.
 type SelectionSet = NonEmpty Selection
 
+-- | Field selection.
 type SelectionSetOpt = [Selection]
 
 -- | Single selection element.
diff --git a/src/Language/GraphQL/AST/Transform.hs b/src/Language/GraphQL/AST/Transform.hs
index f3d2a38..9ecaaac 100644
--- a/src/Language/GraphQL/AST/Transform.hs
+++ b/src/Language/GraphQL/AST/Transform.hs
@@ -1,4 +1,8 @@
 {-# LANGUAGE OverloadedStrings #-}
+
+-- | After the document is parsed, before getting executed the AST is
+--   transformed into a similar, simpler AST. This module is responsible for
+--   this transformation.
 module Language.GraphQL.AST.Transform
     ( document
     ) where
diff --git a/src/Language/GraphQL/Encoder.hs b/src/Language/GraphQL/Encoder.hs
index 11115b1..63a0ef2 100644
--- a/src/Language/GraphQL/Encoder.hs
+++ b/src/Language/GraphQL/Encoder.hs
@@ -31,11 +31,11 @@ data Formatter
     = Minified
     | Pretty Word
 
--- Constructs a formatter for pretty printing.
+-- | Constructs a formatter for pretty printing.
 pretty :: Formatter
 pretty = Pretty 0
 
--- Constructs a formatter for minifying.
+-- | Constructs a formatter for minifying.
 minified :: Formatter
 minified = Minified
 
diff --git a/src/Language/GraphQL/Parser.hs b/src/Language/GraphQL/Parser.hs
index 5ae71b2..6d403b2 100644
--- a/src/Language/GraphQL/Parser.hs
+++ b/src/Language/GraphQL/Parser.hs
@@ -1,5 +1,7 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
+
+-- | @GraphQL@ document parser.
 module Language.GraphQL.Parser
     ( document
     ) where
diff --git a/src/Language/GraphQL/Trans.hs b/src/Language/GraphQL/Trans.hs
index d92aea7..eb78911 100644
--- a/src/Language/GraphQL/Trans.hs
+++ b/src/Language/GraphQL/Trans.hs
@@ -1,3 +1,4 @@
+-- | Monad transformer stack used by the @GraphQL@ resolvers.
 module Language.GraphQL.Trans
     ( ActionT(..)
     ) where
diff --git a/stack.yaml b/stack.yaml
index 2e2e263..b34cbfa 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: lts-14.6
+resolver: lts-14.7
 packages:
 - '.'
 extra-deps: []