diff --git a/lua/nivvie/init.lua b/lua/nivvie/init.lua
index 0666df9..a9c823e 100644
--- a/lua/nivvie/init.lua
+++ b/lua/nivvie/init.lua
@@ -1,9 +1,94 @@
 local nivvie = {}
 
----@param cfg? nivvie.config
+---@param cfg? nivvie.config.proto
 function nivvie.setup(cfg)
   cfg = cfg or {}
   require('nivvie.config').set(cfg)
 end
 
+nivvie.stdin = false
+
+function nivvie.get_uri()
+  return string.gsub(vim.fn.getcwd(), '[^a-zA-Z0-9_.-]', function(s)
+    return '<' .. vim.fn.char2nr(s)
+  end)
+end
+
+---@param name? string
+function nivvie.get_path(name)
+  local sessiondir = require('nivvie.config').get().session_dir
+  return vim.fs.joinpath(sessiondir, (name or nivvie.get_uri()) .. '.vim')
+end
+
+---@param name? string
+function nivvie.save(name)
+  local session_file = nivvie.get_path(name)
+
+  local sessiondir = require('nivvie.config').get().session_dir
+  vim.fn.mkdir(sessiondir, 'p')
+
+  vim.api.nvim_cmd({
+    cmd = 'mksession',
+    bang = true,
+    args = { session_file },
+  }, {})
+end
+
+function nivvie.clean()
+  vim.iter(ipairs(vim.api.nvim_list_bufs())):each(function(_, bufnr)
+    if vim.bo[bufnr].buftype ~= '' then
+      vim.api.nvim_buf_delete(bufnr, { force = true })
+    end
+  end)
+end
+
+---@param name? string
+function nivvie.restore(name)
+  local path = nivvie.get_path(name)
+  if vim.uv.fs_stat(path) then
+    vim.api.nvim_cmd({
+      cmd = 'source',
+      args = { path },
+    }, {})
+    vim.api.nvim_exec_autocmds('SessionLoadPost', {})
+  end
+end
+
+----
+
+function nivvie.isemptysession()
+  if nivvie.stdin then
+    return false
+  end
+
+  if vim.fn.argc() > 0 then
+    return false
+  end
+
+  local bufs = vim.api.nvim_list_bufs()
+  bufs = vim
+    .iter(bufs)
+    :filter(function(buf)
+      return vim.api.nvim_buf_is_valid(buf)
+        and vim.bo[buf].buftype == ''
+        and #vim.api.nvim_buf_get_name(buf) > 0
+    end)
+    :totable()
+
+  return #bufs == 0
+end
+
+--- only restore if necessary
+function nivvie.autorestore()
+  if not require('nivvie.config').get().autorestore then
+    return
+  end
+
+  if not nivvie.isemptysession() then
+    return
+  end
+
+  nivvie.restore()
+end
+
 return nivvie
diff --git a/plugin/nivvie.lua b/plugin/nivvie.lua
index 1699d56..8fc29d6 100644
--- a/plugin/nivvie.lua
+++ b/plugin/nivvie.lua
@@ -4,94 +4,6 @@ end
 
 vim.g.loaded_session = true
 
-local session = {}
-
----@private
-session.stdin = false
-
-function session.get_uri()
-  return string.gsub(vim.fn.getcwd(), '[^a-zA-Z0-9_.-]', function(s)
-    return '<' .. vim.fn.char2nr(s)
-  end)
-end
-
----@param name? string
-function session.get_path(name)
-  local sessiondir = require('nivvie.config').get().session_dir
-  return vim.fs.joinpath(sessiondir, (name or session.get_uri()) .. '.vim')
-end
-
----@param name? string
-function session.save(name)
-  local session_file = session.get_path(name)
-
-  local sessiondir = require('nivvie.config').get().session_dir
-  vim.fn.mkdir(sessiondir, 'p')
-
-  vim.api.nvim_cmd({
-    cmd = 'mksession',
-    bang = true,
-    args = { session_file },
-  }, {})
-end
-
-function session.clean()
-  vim.iter(ipairs(vim.api.nvim_list_bufs())):each(function(_, bufnr)
-    if vim.bo[bufnr].buftype ~= '' then
-      vim.api.nvim_buf_delete(bufnr, { force = true })
-    end
-  end)
-end
-
----@param name? string
-function session.restore(name)
-  local path = session.get_path(name)
-  if vim.uv.fs_stat(path) then
-    vim.api.nvim_cmd({
-      cmd = 'source',
-      args = { path },
-    }, {})
-    vim.api.nvim_exec_autocmds('SessionLoadPost', {})
-  end
-end
-
-----
-
-function session.isemptysession()
-  if session.stdin then
-    return false
-  end
-
-  if vim.fn.argc() > 0 then
-    return false
-  end
-
-  local bufs = vim.api.nvim_list_bufs()
-  bufs = vim
-    .iter(bufs)
-    :filter(function(buf)
-      return vim.api.nvim_buf_is_valid(buf)
-        and vim.bo[buf].buftype == ''
-        and #vim.api.nvim_buf_get_name(buf) > 0
-    end)
-    :totable()
-
-  return #bufs == 0
-end
-
---- only restore if necessary
-function session.autorestore()
-  if not require('nivvie.config').get().autorestore then
-    return
-  end
-
-  if not session.isemptysession() then
-    return
-  end
-
-  session.restore()
-end
-
 local group = vim.api.nvim_create_augroup('nivvie', { clear = true })
 
 vim.api.nvim_create_autocmd({ 'VimLeavePre' }, {
@@ -100,28 +12,28 @@ vim.api.nvim_create_autocmd({ 'VimLeavePre' }, {
     if not require('nivvie.config').get().autosave then
       return
     end
-    session.clean()
-    session.save()
+    require('nivvie').clean()
+    require('nivvie').save()
   end,
 })
 
 vim.api.nvim_create_autocmd({ 'StdinReadPost' }, {
   group = group,
   callback = function()
-    session.stdin = true
+    require('nivvie').stdin = true
   end,
 })
 
 vim.schedule(function()
   vim.api.nvim_create_user_command('Nivvie', function(args)
     if args.fargs[1] == 'save' then
-      session.save(args.fargs[2])
+      require('nivvie').save(args.fargs[2])
       return
     elseif args.fargs[1] == 'restore' then
-      session.restore(args.fargs[2])
+      require('nivvie').restore(args.fargs[2])
       return
     elseif args.fargs[1] == 'delete' then
-      local path = session.get_path(args.fargs[2])
+      local path = require('nivvie').get_path(args.fargs[2])
       if vim.uv.fs_stat(path) then
         vim.uv.fs_unlink(path)
       end
@@ -142,7 +54,7 @@ end)
 
 if vim.v.vim_did_enter > 0 then
   vim.schedule(function()
-    session.autorestore()
+    require('nivvie').autorestore()
   end)
   return
 end
@@ -151,7 +63,7 @@ vim.api.nvim_create_autocmd({ 'VimEnter' }, {
   group = group,
   callback = function()
     vim.schedule(function()
-      session.autorestore()
+      require('nivvie').autorestore()
     end)
   end,
 })