diff --git a/src/trick.gleam b/src/trick.gleam
index 6237087..74c6f38 100644
--- a/src/trick.gleam
+++ b/src/trick.gleam
@@ -201,3 +201,30 @@ pub fn greater_than_or_equal_float(
 ) -> Expression(Float) {
   binary_operator(left, ">=.", right)
 }
+
+fn unary_operator(operator: String, value: Expression(a)) -> Expression(a) {
+  [doc.from_string(operator), value.document] |> doc.concat |> Expression
+}
+
+pub fn negate_int(value: Expression(Int)) -> Expression(Int) {
+  unary_operator("-", value)
+}
+
+pub fn negate_bool(value: Expression(Bool)) -> Expression(Bool) {
+  unary_operator("!", value)
+}
+// TODO:
+// BitString
+// Block
+// Call
+// Case
+// Echo
+// FieldAccess
+// Float
+// Fn
+// FnCapture
+// Pipes
+// RecordUpdate
+// Tuple
+// TupleIndex
+// Variable
diff --git a/test/trick_test.gleam b/test/trick_test.gleam
index d543292..979ad6b 100644
--- a/test/trick_test.gleam
+++ b/test/trick_test.gleam
@@ -130,3 +130,11 @@ pub fn binary_operator_test() {
     |> trick.expression_to_string
     == "False != False"
 }
+
+pub fn unary_operator_test() {
+  assert 10 |> trick.int |> trick.negate_int |> trick.expression_to_string
+    == "-10"
+
+  assert False |> trick.bool |> trick.negate_bool |> trick.expression_to_string
+    == "!False"
+}