Store project local variables (property) using Projectile and Symbol Plists.
The name of this package has projectile- in the prefix, but it can now be executed without depending on it.
(projectile-variable-put 'foo-value 2) ;; Store property 'foo-value
(projectile-variable-get 'foo-value) ;;=> 2
;; Return all project local property list
(projectile-variable-plist)
;; Return project local property list filterd by prefix "foo-"
(projectile-variable-plist "foo-")
;; Return all project local properties as association list (alist)
(projectile-variable-alist)
;; Return project local properties alist filterd by prefix "foo-"
(projectile-variable-alist "foo-")