diff --git a/include/iris/enum_bitops.hpp b/include/iris/enum_bitops.hpp
new file mode 100644
index 0000000..f2d2434
--- /dev/null
+++ b/include/iris/enum_bitops.hpp
@@ -0,0 +1,113 @@
+#ifndef IRIS_ENUM_BITOPS_HPP
+#define IRIS_ENUM_BITOPS_HPP
+
+// SPDX-License-Identifier: MIT
+
+#include <concepts>
+#include <type_traits>
+#include <utility>
+
+#ifndef NDEBUG
+#include <bit>
+#endif
+
+#include <cassert>
+
+namespace iris {
+
+template<class T>
+struct bitops_enabled : std::false_type {};
+
+template<class T>
+constexpr bool bitops_enabled_v = bitops_enabled<T>::value;
+
+namespace detail {
+
+template<class T>
+concept bitops_enum_has_min_bit = std::same_as<std::remove_const_t<decltype(bitops_enabled<T>::min_bit)>, int>;
+
+template<class T>
+concept bitops_enum_has_max_bit = std::same_as<std::remove_const_t<decltype(bitops_enabled<T>::max_bit)>, int>;
+
+} // detail
+
+template<class T>
+concept BitopsEnabledEnum = std::is_enum_v<T> && bitops_enabled_v<T>;
+
+inline namespace bitops_operators {
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T operator~(T a) noexcept
+{
+    return static_cast<T>(~std::to_underlying(a));
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T operator|(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return static_cast<T>(std::to_underlying(a) | std::to_underlying(b));
+}
+
+template<BitopsEnabledEnum T>
+constexpr T& operator|=(T& a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return a = a | b;
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T operator&(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return static_cast<T>(std::to_underlying(a) & std::to_underlying(b));
+}
+
+template<BitopsEnabledEnum T>
+constexpr T& operator&=(T& a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return a = a & b;
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T operator^(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return static_cast<T>(std::to_underlying(a) ^ std::to_underlying(b));
+}
+
+template<BitopsEnabledEnum T>
+constexpr T& operator^=(T& a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return a = a ^ b;
+}
+
+} // bitops_operators
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr bool contains(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return (std::to_underlying(a) & std::to_underlying(b)) == std::to_underlying(b);
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr bool contains_single_bit(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    assert(std::has_single_bit(std::to_underlying(b)));
+    return std::to_underlying(a) & std::to_underlying(b);
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr bool contains_any_bit(T a, T b) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    return std::to_underlying(a) & std::to_underlying(b);
+}
+
+} // iris
+
+#endif
diff --git a/include/iris/enum_bitops_algorithm.hpp b/include/iris/enum_bitops_algorithm.hpp
new file mode 100644
index 0000000..cf7f7fc
--- /dev/null
+++ b/include/iris/enum_bitops_algorithm.hpp
@@ -0,0 +1,35 @@
+#ifndef IRIS_ENUM_BITOPS_ALGORITHM_HPP
+#define IRIS_ENUM_BITOPS_ALGORITHM_HPP
+
+// SPDX-License-Identifier: MIT
+
+#include <iris/enum_bitops.hpp>
+
+#include <limits>
+#include <ranges>
+#include <utility>
+
+namespace iris {
+
+template <BitopsEnabledEnum T>
+[[nodiscard]] constexpr auto each_bit(T flags) noexcept
+{
+    static_assert(std::is_unsigned_v<std::underlying_type_t<T>>);
+    static_assert(detail::bitops_enum_has_max_bit<T>);
+    static_assert(bitops_enabled<T>::max_bit < std::numeric_limits<std::underlying_type_t<T>>::digits);
+
+    if constexpr (detail::bitops_enum_has_min_bit<T>) {
+    static_assert(bitops_enabled<T>::min_bit <= bitops_enabled<T>::max_bit);
+        return std::views::iota(bitops_enabled<T>::min_bit, bitops_enabled<T>::max_bit + 1)
+            | std::views::filter([cat = std::to_underlying(flags)](int i) constexpr noexcept -> bool { return (cat >> i) & 1; })
+            | std::views::transform([](int i) constexpr noexcept { return static_cast<T>(static_cast<std::underlying_type_t<T>>(1) << i); });
+    } else {
+        return std::views::iota(0, bitops_enabled<T>::max_bit + 1)
+            | std::views::filter([cat = std::to_underlying(flags)](int i) constexpr noexcept -> bool { return (cat >> i) & 1; })
+            | std::views::transform([](int i) constexpr noexcept { return static_cast<T>(static_cast<std::underlying_type_t<T>>(1) << i); });
+    }
+}
+
+} // iris
+
+#endif
diff --git a/include/iris/enum_bitops_io.hpp b/include/iris/enum_bitops_io.hpp
new file mode 100644
index 0000000..a38257a
--- /dev/null
+++ b/include/iris/enum_bitops_io.hpp
@@ -0,0 +1,97 @@
+#ifndef IRIS_ENUM_BITOPS_IO_HPP
+#define IRIS_ENUM_BITOPS_IO_HPP
+
+// SPDX-License-Identifier: MIT
+
+#include <iris/string.hpp>
+#include <iris/enum_bitops.hpp>
+
+#include <ostream>
+#include <format>
+#include <ranges>
+#include <string>
+#include <string_view>
+#include <utility>
+
+namespace iris {
+
+inline namespace bitops_operators {
+
+template<BitopsEnabledEnum T>
+std::ostream& operator<<(std::ostream& os, T const& val)
+{
+    using std::to_string;
+
+    if constexpr (requires {
+        { to_string(val) } -> std::convertible_to<std::string const&>;
+    }) {
+        return os << to_string(val);
+    } else {
+        return os << std::to_underlying(val);
+    }
+}
+
+} // bitops_operators
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T parse_flag(StringLike auto const& str) noexcept
+{
+    return bitops_enabled<T>::parse(std::basic_string_view{str});
+}
+
+template<BitopsEnabledEnum T>
+[[nodiscard]] constexpr T parse_flags(StringLike auto const& str, StringLike auto const& delim) noexcept
+{
+    using namespace iris::bitops_operators;
+
+    std::basic_string_view str_sv{str};
+    std::basic_string_view delim_sv{delim};
+
+    T res{};
+
+    for (auto const& r : str_sv | std::views::split(delim_sv)) {
+        std::basic_string_view const part_str{r.begin(), r.end()};
+
+        auto const part = iris::parse_flag<T>(part_str);
+        if (part == T{}) {
+            return T{};
+        }
+        res |= part;
+    }
+
+    return res;
+}
+
+} // iris
+
+namespace std {
+
+template<::iris::BitopsEnabledEnum T, class CharT>
+struct formatter<T, CharT> : formatter<std::underlying_type_t<T>, CharT>
+{
+    using base_formatter = formatter<std::underlying_type_t<T>, CharT>;
+
+    template<class Context>
+    constexpr auto parse(Context& ctx)
+    {
+        if (ctx.begin() == ctx.end()) return ctx.end();
+        has_format_spec_ = true;
+        return base_formatter::parse(ctx);
+    }
+
+    template<class Context>
+    auto format(T const& val, Context& ctx) const
+    {
+        if (has_format_spec_) {
+            return base_formatter::format(std::to_underlying(val), ctx);
+        }
+        return format_to(ctx.out(), "{}", to_string(val));
+    }
+
+private:
+    bool has_format_spec_ = false;
+};
+
+} // std
+
+#endif
diff --git a/include/iris/string.hpp b/include/iris/string.hpp
new file mode 100644
index 0000000..131432e
--- /dev/null
+++ b/include/iris/string.hpp
@@ -0,0 +1,18 @@
+#ifndef IRIS_STRING_HPP
+#define IRIS_STRING_HPP
+
+// SPDX-License-Identifier: MIT
+
+#include <string>
+#include <string_view>
+
+namespace iris {
+
+template<class T>
+concept StringLike = requires(T t) {
+    std::basic_string_view{t};
+};
+
+} // iris
+
+#endif
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 8a34d20..67b72e9 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -139,8 +139,9 @@ if(PROJECT_IS_TOP_LEVEL)
 
     set(
         IRIS_TEST_IRIS_TESTS
-        type_traits
         core
+        type_traits
+        enum
         indirect
     )
 
diff --git a/test/enum.cpp b/test/enum.cpp
new file mode 100644
index 0000000..ac88b16
--- /dev/null
+++ b/test/enum.cpp
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: MIT
+
+#include "iris_test.hpp"
+
+#include <iris/enum_bitops.hpp>
+#include <iris/enum_bitops_algorithm.hpp>
+#include <iris/enum_bitops_io.hpp>
+
+#include <algorithm>
+#include <ranges>
+#include <string_view>
+#include <utility>
+#include <vector>
+
+#include <cstdint>
+
+enum class MyFlags : std::uint8_t
+{
+    FOO = 1 << 0,
+    BAR = 1 << 1,
+    BAZ = 1 << 2,
+};
+
+enum class SpellType : std::uint8_t
+{
+    TYPE_ATTACK  = 1 << 0,
+    TYPE_DEFENSE = 1 << 1,
+
+    ATTR_FIRE    = 1 << 2,
+    ATTR_WATER   = 1 << 3,
+    ATTR_THUNDER = 1 << 4,
+};
+
+template <>
+struct iris::bitops_enabled<MyFlags> : std::true_type
+{
+    static MyFlags parse(std::string_view sv) noexcept
+    {
+        using enum MyFlags;
+        if (sv == "foo") return FOO;
+        if (sv == "bar") return BAR;
+        if (sv == "baz") return BAZ;
+        return {};
+    }
+};
+
+template <>
+struct iris::bitops_enabled<SpellType> : std::true_type
+{
+    static constexpr int min_bit = 2;
+    static constexpr int max_bit = 4;
+};
+
+TEST_CASE("enum")
+{
+    using namespace iris::bitops_operators;
+
+    using enum MyFlags;
+
+    CHECK((~FOO == static_cast<MyFlags>(~std::to_underlying(FOO))));
+
+    CHECK(((FOO & BAR) == static_cast<MyFlags>(std::to_underlying(FOO) & std::to_underlying(BAR))));
+    CHECK(((FOO ^ BAR) == static_cast<MyFlags>(std::to_underlying(FOO) ^ std::to_underlying(BAR))));
+    CHECK(((FOO | BAR) == static_cast<MyFlags>(std::to_underlying(FOO) | std::to_underlying(BAR))));
+
+    CHECK( iris::contains(FOO, FOO));
+    CHECK(!iris::contains(FOO, BAR));
+    CHECK( iris::contains(FOO | BAR, FOO));
+    CHECK(!iris::contains(FOO | BAR, BAZ));
+    CHECK(!iris::contains(FOO |       BAZ, FOO | BAR));
+    CHECK(!iris::contains(      BAR | BAZ, FOO | BAR));
+    CHECK( iris::contains(FOO | BAR | BAZ, FOO | BAR));
+
+    CHECK( iris::contains_any_bit(FOO, FOO));
+    CHECK(!iris::contains_any_bit(FOO, BAR));
+    CHECK( iris::contains_any_bit(FOO | BAR, FOO));
+    CHECK(!iris::contains_any_bit(FOO | BAR, BAZ));
+    CHECK( iris::contains_any_bit(FOO |       BAZ, FOO | BAR));
+    CHECK( iris::contains_any_bit(      BAR | BAZ, FOO | BAR));
+    CHECK( iris::contains_any_bit(FOO | BAR | BAZ, FOO | BAR));
+
+    CHECK( iris::contains_single_bit(FOO, FOO));
+    CHECK(!iris::contains_single_bit(FOO, BAR));
+    CHECK( iris::contains_single_bit(FOO | BAR, FOO));
+    CHECK(!iris::contains_single_bit(FOO | BAR, BAZ));
+
+    CHECK((iris::parse_flag<MyFlags>("foo") == FOO));
+    CHECK((iris::parse_flag<MyFlags>("bar") == BAR));
+    CHECK((iris::parse_flag<MyFlags>("baz") == BAZ));
+    CHECK((iris::parse_flag<MyFlags>("yay") == MyFlags{}));
+
+    CHECK((iris::parse_flags<MyFlags>("foo", "|") == FOO));
+    CHECK((iris::parse_flags<MyFlags>("yay", "|") == MyFlags{}));
+
+    CHECK((iris::parse_flags<MyFlags>("foo|bar", "|") == (FOO | BAR)));
+    CHECK((iris::parse_flags<MyFlags>("foo|yay", "|") == MyFlags{}));
+    CHECK((iris::parse_flags<MyFlags>("foo,bar", "|") == MyFlags{}));
+
+    CHECK(std::ranges::equal(
+        iris::each_bit(SpellType::TYPE_ATTACK | SpellType::ATTR_FIRE | SpellType::ATTR_THUNDER),
+        std::vector{SpellType::ATTR_FIRE, SpellType::ATTR_THUNDER}
+    ));
+
+    CHECK(std::ranges::equal(
+        iris::each_bit(static_cast<SpellType>(static_cast<std::underlying_type_t<SpellType>>(-1))),
+        std::vector{SpellType::ATTR_FIRE, SpellType::ATTR_WATER, SpellType::ATTR_THUNDER}
+    ));
+}