Add cython-specific flag and packages

modules/lang/python/config.el

@@ -276,3 +276,20 @@ called.")
   (defadvice! +python--dont-auto-install-server-a ()
     :override #'lsp-python-ms--command-string
     lsp-python-ms-executable))
+
+(use-package! cython-mode
+  :when (featurep! +cython)
+  :mode (("\\.pyx\\'" . cython-mode)
+         ("\\.pxd\\'" . cython-mode)
+         ("\\.pxi\\'" . cython-mode))
+  :config
+  (setq cython-default-compile-format "cython -a %s")
+  (map! :map cython-mode-map
+        :localleader
+        :prefix "c"
+        :desc "Cython compile buffer"    "c" #'cython-compile)
+  )
+
+(use-package! flycheck-cython
+  :when (featurep! :tools flycheck)
+  :after cython-mode)

modules/lang/python/packages.el

@@ -3,6 +3,10 @@
 
 ;; Major modes
 (package! pip-requirements)
+(when (featurep! +cython)
+  (package! cython-mode)
+  (when (featurep! :tools flycheck)
+    (package! flycheck-cython)))
 
 ;; LSP
 (when (featurep! +lsp)