diff --git a/src/indexer.hh b/src/indexer.hh
index e75d39be..e435b39d 100644
--- a/src/indexer.hh
+++ b/src/indexer.hh
@@ -4,7 +4,6 @@
 #pragma once
 
 #include "lsp.hh"
-#include "maybe.hh"
 #include "position.hh"
 #include "serializer.hh"
 #include "utils.hh"
diff --git a/src/maybe.hh b/src/maybe.hh
deleted file mode 100644
index f0adf8a7..00000000
--- a/src/maybe.hh
+++ /dev/null
@@ -1,48 +0,0 @@
-// Copyright 2017-2018 ccls Authors
-// SPDX-License-Identifier: Apache-2.0
-
-#pragma once
-
-#include <optional>
-
-#include <utility>
-
-namespace ccls {
-// Like std::optional, but the stored data is responsible for containing the
-// empty state. T should define a function `bool T::Valid()`.
-template <typename T> class Maybe {
-  T storage;
-
-public:
-  constexpr Maybe() = default;
-  Maybe(const Maybe &) = default;
-  Maybe(std::nullopt_t) {}
-  Maybe(const T &x) : storage(x) {}
-  Maybe(T &&x) : storage(std::forward<T>(x)) {}
-
-  Maybe &operator=(const Maybe &) = default;
-  Maybe &operator=(const T &x) {
-    storage = x;
-    return *this;
-  }
-
-  const T *operator->() const { return &storage; }
-  T *operator->() { return &storage; }
-  const T &operator*() const { return storage; }
-  T &operator*() { return storage; }
-
-  bool Valid() const { return storage.Valid(); }
-  explicit operator bool() const { return Valid(); }
-  operator std::optional<T>() const {
-    if (Valid())
-      return storage;
-    return std::nullopt;
-  }
-
-  void operator=(std::optional<T> &&o) { storage = o ? *o : T(); }
-
-  // Does not test if has_value()
-  bool operator==(const Maybe &o) const { return storage == o.storage; }
-  bool operator!=(const Maybe &o) const { return !(*this == o); }
-};
-} // namespace ccls
diff --git a/src/position.hh b/src/position.hh
index f92d24b7..61a6429c 100644
--- a/src/position.hh
+++ b/src/position.hh
@@ -3,7 +3,6 @@
 
 #pragma once
 
-#include "maybe.hh"
 #include "utils.hh"
 
 #include <stdint.h>
diff --git a/src/serializer.hh b/src/serializer.hh
index b82da60d..0e68671c 100644
--- a/src/serializer.hh
+++ b/src/serializer.hh
@@ -3,7 +3,7 @@
 
 #pragma once
 
-#include "maybe.hh"
+#include "utils.hh"
 
 #include <llvm/Support/Compiler.h>
 
diff --git a/src/utils.hh b/src/utils.hh
index 3a5cdbd1..330259c9 100644
--- a/src/utils.hh
+++ b/src/utils.hh
@@ -9,6 +9,7 @@
 #include <iterator>
 #include <memory>
 #include <string>
+#include <utility>
 #include <vector>
 
 namespace llvm {
@@ -87,4 +88,42 @@ inline void hash_combine(std::size_t &seed, const T &v, Rest... rest) {
   }
 
 std::string GetDefaultResourceDirectory();
+
+// Like std::optional, but the stored data is responsible for containing the
+// empty state. T should define a function `bool T::Valid()`.
+template <typename T> class Maybe {
+  T storage;
+
+public:
+  constexpr Maybe() = default;
+  Maybe(const Maybe &) = default;
+  Maybe(std::nullopt_t) {}
+  Maybe(const T &x) : storage(x) {}
+  Maybe(T &&x) : storage(std::forward<T>(x)) {}
+
+  Maybe &operator=(const Maybe &) = default;
+  Maybe &operator=(const T &x) {
+    storage = x;
+    return *this;
+  }
+
+  const T *operator->() const { return &storage; }
+  T *operator->() { return &storage; }
+  const T &operator*() const { return storage; }
+  T &operator*() { return storage; }
+
+  bool Valid() const { return storage.Valid(); }
+  explicit operator bool() const { return Valid(); }
+  operator std::optional<T>() const {
+    if (Valid())
+      return storage;
+    return std::nullopt;
+  }
+
+  void operator=(std::optional<T> &&o) { storage = o ? *o : T(); }
+
+  // Does not test if has_value()
+  bool operator==(const Maybe &o) const { return storage == o.storage; }
+  bool operator!=(const Maybe &o) const { return !(*this == o); }
+};
 } // namespace ccls