diff --git a/include/gsl/gsl b/include/gsl/gsl
index c620a09..6d832c8 100644
--- a/include/gsl/gsl
+++ b/include/gsl/gsl
@@ -144,3 +144,5 @@ struct hash<gsl::not_null<T>>
 #endif // defined(_MSC_VER) && _MSC_VER < 1910
 
 #endif // GSL_GSL_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/gsl_algorithm b/include/gsl/gsl_algorithm
index 9a5c36b..c6f8aa5 100644
--- a/include/gsl/gsl_algorithm
+++ b/include/gsl/gsl_algorithm
@@ -57,3 +57,5 @@ void copy(span<SrcElementType, SrcExtent> src, span<DestElementType, DestExtent>
 #endif // _MSC_VER
 
 #endif // GSL_ALGORITHM_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/gsl_assert b/include/gsl/gsl_assert
index 04f34b3..ef85093 100644
--- a/include/gsl/gsl_assert
+++ b/include/gsl/gsl_assert
@@ -83,3 +83,5 @@ struct fail_fast : public std::runtime_error
 #endif
 
 #endif // GSL_CONTRACTS_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/gsl_byte b/include/gsl/gsl_byte
index 6c05dd4..a8d09af 100644
--- a/include/gsl/gsl_byte
+++ b/include/gsl/gsl_byte
@@ -153,3 +153,5 @@ inline constexpr byte to_byte() noexcept
 #endif // _MSC_VER
 
 #endif // GSL_BYTE_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/gsl_util b/include/gsl/gsl_util
index 8961539..47bdaf9 100644
--- a/include/gsl/gsl_util
+++ b/include/gsl/gsl_util
@@ -173,3 +173,5 @@ inline constexpr const T& at(std::initializer_list<T> cont, std::ptrdiff_t index
 #endif // _MSC_VER
 
 #endif // GSL_UTIL_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/multi_span b/include/gsl/multi_span
index 9100e69..28f61b2 100644
--- a/include/gsl/multi_span
+++ b/include/gsl/multi_span
@@ -2219,3 +2219,5 @@ general_span_iterator<Span> operator+(typename general_span_iterator<Span>::diff
 #endif // _MSC_VER
 
 #endif // GSL_MULTI_SPAN_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/span b/include/gsl/span
index 957c9e6..7a39440 100644
--- a/include/gsl/span
+++ b/include/gsl/span
@@ -699,3 +699,5 @@ inline constexpr ElementType& at(const span<ElementType, Extent>& s, std::ptrdif
 #endif // _MSC_VER
 
 #endif // GSL_SPAN_H
+
+// vim: set filetype=cpp:
diff --git a/include/gsl/string_span b/include/gsl/string_span
index cd7f4b8..f09ff09 100644
--- a/include/gsl/string_span
+++ b/include/gsl/string_span
@@ -850,3 +850,5 @@ bool operator>=(const T& one, gsl::basic_string_span<CharT, Extent> other) GSL_N
 #endif // _MSC_VER
 
 #endif // GSL_STRING_SPAN_H
+
+// vim: set filetype=cpp: