my-nvim-setup/lua/core/hooks.lua

local hooks, M = {}, {}
local allowed_hooks = {
   "install_plugins",
   "setup_mappings",
   "ready",
}

local function has_value(tab, val)
   for _, value in ipairs(tab) do
      if value == val then
         return true
      end
   end
end

M.add = function(name, fn)
   if not (has_value(allowed_hooks, name)) then
      print("Custom lua uses unallowed hook " .. name)
   end
   if hooks[name] == nil then
      hooks[name] = {}
   end
   table.insert(hooks[name], fn)
end

M.run = function(name, args)
   if hooks[name] ~= nil then
      for _, hook in pairs(hooks[name]) do
         hook(args)
      end
   end
end

return M