diff --git a/.clang-format b/.clang-format
new file mode 100644
index 0000000..5d94bf9
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,74 @@
+---
+Language:        Cpp
+# BasedOnStyle:  LLVM
+AccessModifierOffset: -4
+ConstructorInitializerIndentWidth: 4
+AlignEscapedNewlinesLeft: false
+AlignTrailingComments: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortBlocksOnASingleLine: false
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: All
+AlwaysBreakTemplateDeclarations: true
+AlwaysBreakBeforeMultilineStrings: false
+BreakBeforeBinaryOperators: false
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: false
+BinPackParameters: true
+ColumnLimit:     80
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+DerivePointerAlignment: false
+ExperimentalAutoDetectBinPacking: false
+IndentCaseLabels: false
+IndentWrappedFunctionNames: false
+IndentFunctionDeclarationAfterType: false
+MaxEmptyLinesToKeep: 1
+KeepEmptyLinesAtTheStartOfBlocks: true
+NamespaceIndentation: None
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakBeforeFirstCallParameter: 19
+PenaltyBreakComment: 300
+PenaltyBreakString: 1000
+PenaltyBreakFirstLessLess: 120
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 60
+PointerAlignment: Right
+SpacesBeforeTrailingComments: 1
+Cpp11BracedListStyle: true
+Standard:        Cpp11
+IndentWidth:     4
+TabWidth:        4
+UseTab:          Never
+BreakBeforeBraces: Attach
+SpacesInParentheses: false
+SpacesInAngles:  false
+SpaceInEmptyParentheses: false
+SpacesInCStyleCastParentheses: false
+SpacesInContainerLiterals: true
+SpaceBeforeAssignmentOperators: true
+ContinuationIndentWidth: 4
+CommentPragmas:  '^ IWYU pragma:'
+ForEachMacros:   [ Q_FOREACH, BOOST_FOREACH ]
+SpaceBeforeParens: ControlStatements
+DisableFormat:   false
+SortIncludes: true
+IncludeCategories:
+  # C system headers.
+  - Regex:    '^[<"](aio|arpa/inet|assert|complex|cpio|ctype|curses|dirent|dlfcn|errno|fcntl|fenv|float|fmtmsg|fnmatch|ftw|glob|grp|iconv|inttypes|iso646|langinfo|libgen|limits|locale|math|monetary|mqueue|ndbm|netdb|net/if|netinet/in|netinet/tcp|nl_types|poll|pthread|pwd|regex|sched|search|semaphore|setjmp|signal|spawn|stdalign|stdarg|stdatomic|stdbool|stddef|stdint|stdio|stdlib|stdnoreturn|string|strings|stropts|sys/ipc|syslog|sys/mman|sys/msg|sys/resource|sys/select|sys/sem|sys/shm|sys/socket|sys/stat|sys/statvfs|sys/time|sys/times|sys/types|sys/uio|sys/un|sys/utsname|sys/wait|tar|term|termios|tgmath|threads|time|trace|uchar|ulimit|uncntrl|unistd|utime|utmpx|wchar|wctype|wordexp)\.h[">]$'
+    Priority: 20
+  # C++ system headers (as of C++17).
+  - Regex:    '^[<"](algorithm|any|array|atomic|bitset|cassert|ccomplex|cctype|cerrno|cfenv|cfloat|charconv|chrono|cinttypes|ciso646|climits|clocale|cmath|codecvt|complex|condition_variable|csetjmp|csignal|cstdalign|cstdarg|cstdbool|cstddef|cstdint|cstdio|cstdlib|cstring|ctgmath|ctime|cuchar|cwchar|cwctype|deque|exception|execution|filesystem|forward_list|fstream|functional|future|initializer_list|iomanip|ios|iosfwd|iostream|istream|iterator|limits|list|locale|map|memory|memory_resource|mutex|new|numeric|optional|ostream|queue|random|ratio|regex|scoped_allocator|set|shared_mutex|sstream|stack|stdexcept|streambuf|string|string_view|strstream|system_error|thread|tuple|type_traits|typeindex|typeinfo|unordered_map|unordered_set|utility|valarray|variant|vector)[">]$'
+    Priority: 30
+  # Other libraries' h files (with angles).
+  - Regex:    '^<'
+    Priority: 40
+  # Your project's h files.
+  - Regex:    '^[<"]fcitx'
+    Priority: 45
+  # Other libraries' h files (with quotes).
+  - Regex:    '^"'
+    Priority: 50
+...
+