diff --git a/mello.cabal b/mello.cabal
--- a/mello.cabal
+++ b/mello.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           mello
-version:        0.4.0
+version:        0.5.0
 synopsis:       No-fuss syntax with s-expressions
 description:    Please see the README on GitHub at <https://github.com/ejconlon/mello#readme>
 category:       Parsing
diff --git a/src/Mello/Parse.hs b/src/Mello/Parse.hs
--- a/src/Mello/Parse.hs
+++ b/src/Mello/Parse.hs
@@ -14,7 +14,7 @@
 
 import Bowtie (Memo, pattern MemoP)
 import Control.Monad (guard, unless, void)
-import Data.Char (isSpace)
+import Data.Char (isDigit, isSpace)
 import Data.Sequence (Seq (..))
 import Data.Text (Text)
 import Data.Text qualified as T
@@ -28,7 +28,6 @@
   , isAtomStart
   , isCharStart
   , isListStart
-  , isNumStart
   , isQuoteStart
   , isStringStart
   , isSymCont
@@ -153,11 +152,18 @@
     pure (SexpListF b ss)
   quoteP = L.charP_ '`' *> fmap SexpQuoteF rootP
   unquoteP = L.charP_ ',' *> fmap SexpUnquoteF rootP
+  guardNumStartP = do
+    c <- L.headP
+    if isDigit c
+      then pure ()
+      else do
+        guard (c == '-')
+        void (L.headP >>= guard . isDigit)
   atomP =
     SexpAtomF
       <$> L.commitP
-        [ (guard1P isSymStart, L.labelP "sym" (fmap AtomSym symP))
-        , (guard1P isNumStart, L.labelP "num" (fmap (either AtomInt AtomSci) L.numP))
+        [ (guardNumStartP, L.labelP "num" (fmap (either AtomInt AtomSci) L.numP))
+        , (guard1P isSymStart, L.labelP "sym" (fmap AtomSym symP))
         , (guard1P isStringStart, L.labelP "str" (fmap AtomStr stringLitP))
         , (guard1P isCharStart, L.labelP "char" (fmap AtomChar charLitP))
         ]
diff --git a/src/Mello/Text.hs b/src/Mello/Text.hs
--- a/src/Mello/Text.hs
+++ b/src/Mello/Text.hs
@@ -75,7 +75,6 @@
       || isCharStart c
       || isQuoteStart c
       || isUnquoteStart c
-      || isDigit c
 isListStart c = c == '(' || c == '{' || c == '['
 isListEnd c = c == ')' || c == '}' || c == ']'
 isCharStart c = c == '\''
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -44,6 +44,13 @@
     , parseCaseAs "unquote" ",1" (SexpUnquote 1)
     , parseCaseAs "list" "(1 2)" (SexpList BraceParen [1, 2])
     , parseCaseAs "doc" ";|X\n;Y\n1" (SexpDoc (Doc ["X", "Y"]) 1)
+    , parseCaseAs "atom int neg" "-1" (SexpAtom (AtomInt (-1)))
+    , parseCaseAs "atom sym special 1" "_y-3z" (SexpAtom (AtomSym "_y-3z"))
+    , parseCaseAs "atom sym special 2" ">=" (SexpAtom (AtomSym ">="))
+    , parseCaseAs "atom sym special 3" "<=" (SexpAtom (AtomSym "<="))
+    , parseCaseAs "atom sym special 4" "=>" (SexpAtom (AtomSym "=>"))
+    , parseCaseAs "atom sym special 5" "->" (SexpAtom (AtomSym "->"))
+    , parseCaseAs "atom sym special 6" ":x" (SexpAtom (AtomSym ":x"))
     ]
 
 main :: IO ()