diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..8756d6a
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,39 @@
+name: Tests
+
+on: 
+  push:
+    branches-ignore: [master]
+  pull_request:
+    types: [opened, reopened]
+
+jobs:
+  appimage-ubuntu:
+    name: ubuntu
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - run: date +%F > todays-date
+      - name: Restore cache for today's nightly.
+        uses: actions/cache@v2
+        with:
+          path: |
+            build
+          key: ${{ runner.os }}-appimage-${{ hashFiles('todays-date') }}
+
+      - name: Prepare
+        run: |
+          sudo apt install fd-find
+          test -d build || {
+            mkdir -p build
+            wget https://github.com/neovim/neovim/releases/download/nightly/nvim.appimage
+            chmod +x nvim.appimage
+            mv nvim.appimage ./build/nvim
+          }
+          mkdir -p ~/.local/share/nvim/site/pack/vendor/start
+          git clone --depth 1 https://github.com/nvim-lua/plenary.nvim ~/.local/share/nvim/site/pack/vendor/start/plenary.nvim
+          git clone --depth 1 https://github.com/kyazdani42/nvim-web-devicons ~/.local/share/nvim/site/pack/vendor/start/nvim-web-devicons
+          ln -s $(pwd) ~/.local/share/nvim/site/pack/vendor/start
+      - name: Run tests
+        run: |
+            export PATH="${PWD}/build/:${PATH}"
+            make test
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
new file mode 100644
index 0000000..65812e4
--- /dev/null
+++ b/.github/workflows/lint.yml
@@ -0,0 +1,22 @@
+name: Linting
+
+on: 
+  push:
+    branches-ignore: [master]
+  pull_request:
+    types: [opened, reopened]
+
+jobs:
+  build:
+    name: Luacheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Install linter
+        run: |
+          sudo apt-get update
+          sudo apt-get install luarocks
+          sudo luarocks install luacheck
+      - name: Lint
+        run: make lint
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..88c5c2f
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,13 @@
+.DEFAULT_GOAL = check
+
+lint:
+	@luacheck lua/lualine
+	@luacheck tests
+
+format:
+	@for file in `find -name '*.lua'`;do lua-format $$file -i; done;
+
+test:
+	@nvim --headless -u tests/minimal_init.lua -c "PlenaryBustedDirectory tests/ { minimal_init = './tests/minimal_init.lua' }"
+
+check: lint test
diff --git a/tests/helpers.lua b/tests/helpers.lua
new file mode 100644
index 0000000..e9f978b
--- /dev/null
+++ b/tests/helpers.lua
@@ -0,0 +1,35 @@
+local luassert = require 'luassert'
+local M = {}
+
+M.eq = luassert.are.same
+M.neq = luassert.are_not.same
+M.meths = setmetatable({}, {
+  __index = function(_, key) return vim.api['nvim_' .. key] end
+})
+
+-- Checks ouput of a component
+M.assert_component = function(component, opts, result)
+  -- for testing global options
+  if component == nil then component = 'special.function_component' end
+  local comp = require('lualine.components.' .. component):new(opts)
+  M.eq(result, comp:draw(opts.hl))
+end
+
+-- sets defaults for component options
+M.build_component_opts = function(opts)
+  if not opts then opts = {} end
+  if opts[1] == nil then opts[1] = function() return 'test' end end
+  if not opts.self then opts.self = {section = 'lualine_c'} end
+  if not opts.theme then opts.theme = 'gruvbox' end
+  if not opts.hl then opts.hl = '' end
+  if opts.icons_enabled == nil then opts.icons_enabled = true end
+  if not opts.component_separators then
+    opts.component_separators = {'', ''}
+  end
+  if not opts.section_separators then opts.section_separators = {'', ''} end
+  return opts
+end
+
+M.P = function(t) print(vim.inspect(t)) end
+
+return M
diff --git a/tests/minimal_init.lua b/tests/minimal_init.lua
new file mode 100644
index 0000000..3a27414
--- /dev/null
+++ b/tests/minimal_init.lua
@@ -0,0 +1,5 @@
+-- load lualine and plenary
+vim.api.nvim_exec([[
+  set rtp+=.
+  set rtp+=../plenary.nvim
+]], false)
diff --git a/tests/spec/component_spec.lua b/tests/spec/component_spec.lua
new file mode 100644
index 0000000..ac9b174
--- /dev/null
+++ b/tests/spec/component_spec.lua
@@ -0,0 +1,288 @@
+local helpers = require 'tests.helpers'
+
+local eq = helpers.eq
+local neq = helpers.neq
+local assert_component = helpers.assert_component
+local build_component_opts = helpers.build_component_opts
+local stub = require 'luassert.stub'
+
+describe('Component:', function()
+  it('can select separators', function()
+    local opts = build_component_opts()
+    local comp =
+        require('lua.lualine.components.special.function_component'):new(opts)
+    -- correct for lualine_c
+    eq('', comp.options.separator)
+    local opts2 = build_component_opts({self = {section = 'lualine_y'}})
+    local comp2 =
+        require('lua.lualine.components.special.function_component'):new(opts2)
+    -- correct for lualine_u
+    eq('', comp2.options.separator)
+  end)
+
+  it('can provide unique identifier', function()
+    local opts1 = build_component_opts()
+    local comp1 =
+        require('lua.lualine.components.special.function_component'):new(opts1)
+    local opts2 = build_component_opts()
+    local comp2 =
+        require('lua.lualine.components.special.function_component'):new(opts2)
+    neq(comp1.component_no, comp2.component_no)
+  end)
+
+  it('create option highlights', function()
+    local color = {fg = '#224532', bg = '#892345'}
+    local opts1 = build_component_opts({color = color})
+    local hl = require 'lualine.highlight'
+    stub(hl, 'create_component_highlight_group')
+    hl.create_component_highlight_group.returns('MyCompHl')
+    local comp1 =
+        require('lua.lualine.components.special.function_component'):new(opts1)
+    eq('MyCompHl', comp1.options.color_highlight)
+    -- color highlight wan't in options when create_comp_hl was
+    -- called so remove it before assert
+    comp1.options.color_highlight = nil
+    assert.stub(hl.create_component_highlight_group).was_called_with(color,
+                                                                     comp1.options
+                                                                         .component_name,
+                                                                     comp1.options)
+    hl.create_component_highlight_group:revert()
+    local opts2 = build_component_opts({color = 'MyHl'})
+    local comp2 =
+        require('lua.lualine.components.special.function_component'):new(opts2)
+    eq('MyHl', comp2.options.color_highlight_link)
+  end)
+
+  it('can draw', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component(nil, opts, 'test')
+  end)
+
+  it('can apply separators', function()
+    local opts = build_component_opts({padding = 0})
+    assert_component(nil, opts, 'test')
+  end)
+
+  it('can apply default highlight', function()
+    local opts = build_component_opts({padding = 0, hl = '%#My_highlight#'})
+    assert_component(nil, opts, 'test%#My_highlight#')
+  end)
+
+  describe('Global options:', function()
+    it('upper', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        upper = true
+      })
+      assert_component(nil, opts, 'TEST')
+    end)
+
+    it('lower', function()
+      local opts = build_component_opts({
+        function() return 'TeSt' end,
+        component_separators = {'', ''},
+        padding = 0,
+        lower = true
+      })
+      assert_component(nil, opts, 'test')
+    end)
+
+    it('left_padding', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        left_padding = 5
+      })
+      assert_component(nil, opts, '     test')
+    end)
+
+    it('right_padding', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        right_padding = 5
+      })
+      assert_component(nil, opts, 'test     ')
+    end)
+
+    it('padding', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 5
+      })
+      assert_component(nil, opts, '     test     ')
+    end)
+
+    it('icon', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        icon = '0'
+      })
+      assert_component(nil, opts, '0 test')
+    end)
+
+    it('icons_enabled', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        icons_enabled = true,
+        icon = '0'
+      })
+      assert_component(nil, opts, '0 test')
+      local opts2 = build_component_opts(
+                        {
+            component_separators = {'', ''},
+            padding = 0,
+            icons_enabled = false,
+            icon = '0'
+          })
+      assert_component(nil, opts2, 'test')
+    end)
+
+    it('separator', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        separator = '|'
+      })
+      assert_component(nil, opts, 'test|')
+    end)
+
+    it('format', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        format = function(data)
+          return data:sub(1, 1):upper() .. data:sub(2, #data)
+        end
+      })
+      assert_component(nil, opts, 'Test')
+    end)
+
+    it('condition', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        condition = function() return true end
+      })
+      assert_component(nil, opts, 'test')
+      local opts2 = build_component_opts(
+                        {
+            component_separators = {'', ''},
+            padding = 0,
+            condition = function() return false end
+          })
+      assert_component(nil, opts2, '')
+    end)
+
+    it('color', function()
+      local opts = build_component_opts({
+        component_separators = {'', ''},
+        padding = 0,
+        color = 'MyHl'
+      })
+      assert_component(nil, opts, '%#MyHl#test')
+      local opts2 = build_component_opts(
+                        {
+            component_separators = {'', ''},
+            padding = 0,
+            color = {bg = '#230055', fg = '#223344'}
+          })
+      local hl = require 'lualine.highlight'
+      stub(hl, 'component_format_highlight')
+      hl.component_format_highlight.returns('%#MyCompHl#')
+      local comp2 =
+          require('lua.lualine.components.special.function_component'):new(opts2)
+      assert_component(nil, opts2, '%#MyCompHl#test')
+      assert.stub(hl.component_format_highlight).was_called_with(
+          comp2.options.color_highlight)
+      hl.component_format_highlight:revert()
+    end)
+  end)
+end)
+
+describe('Encoding component', function()
+  it('works', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component('encoding', opts, '%{strlen(&fenc)?&fenc:&enc}')
+  end)
+end)
+
+describe('Fileformat component', function()
+  it('works with icons', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    local fmt = vim.bo.fileformat
+    vim.bo.fileformat = 'unix'
+    assert_component('fileformat', opts, '')
+    vim.bo.fileformat = 'dos'
+    assert_component('fileformat', opts, '')
+    vim.bo.fileformat = 'mac'
+    assert_component('fileformat', opts, '')
+    vim.bo.fileformat = fmt
+  end)
+  it('works without icons', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0,
+      icons_enabled = false
+    })
+    assert_component('fileformat', opts, vim.bo.fileformat)
+  end)
+end)
+
+describe('Hostname component', function()
+  it('works', function()
+    stub(vim.loop, 'os_gethostname')
+    vim.loop.os_gethostname.returns('localhost')
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component('hostname', opts, 'localhost')
+    vim.loop.os_gethostname:revert()
+  end)
+end)
+
+describe('Location component', function()
+  it('works', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component('location', opts, '%3l:%-2c')
+  end)
+end)
+
+describe('Progress component', function()
+  it('works', function()
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component('progress', opts, '%3P')
+  end)
+end)
+
+describe('Mode component', function()
+  it('works', function()
+    stub(vim.api, 'nvim_get_mode')
+    vim.api.nvim_get_mode.returns({mode = 'n', blocking = false})
+    local opts = build_component_opts({
+      component_separators = {'', ''},
+      padding = 0
+    })
+    assert_component('mode', opts, 'NORMAL')
+    vim.api.nvim_get_mode:revert()
+  end)
+end)
diff --git a/tests/spec/utils_spec.lua b/tests/spec/utils_spec.lua
new file mode 100644
index 0000000..a559bc2
--- /dev/null
+++ b/tests/spec/utils_spec.lua
@@ -0,0 +1,115 @@
+local helpers = require 'tests.helpers'
+
+local eq = helpers.eq
+local meths = helpers.meths
+local build_component_opts = helpers.build_component_opts
+
+describe('Utils', function()
+  local utils = require('lualine.utils.utils')
+
+  it('can save and restore highlights', function()
+    local hl1 = {'hl1', '#122233', '#445566', 'italic', true}
+    utils.save_highlight(hl1[1], hl1)
+    -- highlight loaded in loaded_highlights table
+    eq(utils.loaded_highlights[hl1[1]], hl1)
+    -- highlight exists works properly
+    eq(utils.highlight_exists('hl1'), true)
+    eq(utils.highlight_exists('hl2'), false)
+    -- highlights can be restored
+    -- hl doesn't exist
+    assert.has_error(function() meths.get_hl_by_name('hl1', true) end,
+                     'Invalid highlight name: hl1')
+    utils.reload_highlights()
+    -- Now hl1 is created
+    eq(meths.get_hl_by_name('hl1', true), {
+      foreground = tonumber(hl1[2]:sub(2, #hl1[2]), 16), -- convert rgb -> int
+      background = tonumber(hl1[3]:sub(2, #hl1[3]), 16), -- convert rgb -> int
+      italic = true
+    })
+    -- highlights can be cleared
+    utils.clear_highlights()
+    eq(utils.highlight_exists('hl1'), false)
+    -- highlight group has been cleared
+    eq(meths.get_hl_by_name('hl1', true), {[true] = 6})
+  end)
+
+  it('can retrive highlight groups', function()
+    local hl2 = {fg = '#aabbcc', bg = '#889977', reverse = true}
+    -- handles non existing hl groups
+    eq(utils.extract_highlight_colors('hl2'), nil)
+    -- create highlight
+    vim.cmd(
+        string.format('hi hl2 guifg=%s guibg=%s gui=reverse', hl2.fg, hl2.bg))
+    -- Can retrive entire highlight table
+    eq(utils.extract_highlight_colors('hl2'), hl2)
+    -- Can retrive specific parts of highlight
+    eq(utils.extract_highlight_colors('hl2', 'fg'), hl2.fg)
+    -- clear hl2
+    vim.cmd 'hi clear hl2'
+  end)
+
+  it('can shrink list with holes', function()
+    local list_with_holes = {
+      '2', '4', '6', nil, '43', nil, '2', '', 'a', '', 'b', ' '
+    }
+    local list_without_holes = {'2', '4', '6', '43', '2', 'a', 'b', ' '}
+    eq(utils.list_shrink(list_with_holes), list_without_holes)
+  end)
+end)
+
+describe('Cterm genarator', function()
+  local cterm = require 'lualine.utils.cterm_colors'
+
+  it('can convert rgb to cterm', function()
+    local colors = {['#112233'] = 235, ['#7928ae'] = 97, ['#017bdc'] = 68}
+    for rgb, ct in pairs(colors) do
+      eq(cterm.get_cterm_color(rgb), tostring(ct))
+    end
+  end)
+end)
+
+describe('Section genarator', function()
+  local sec = require 'lualine.utils.section'
+  it('can draw', function()
+    local opts = build_component_opts()
+    local section = {
+      require('lua.lualine.components.special.function_component'):new(opts),
+      require('lua.lualine.components.special.function_component'):new(opts)
+    }
+    eq('%#MyHl# test %#MyHl# test ', sec.draw_section(section, '%#MyHl#'))
+  end)
+
+  it('can remove separators from component with custom colors', function()
+    local opts = build_component_opts()
+    local opts_colored = build_component_opts({color = 'MyColor'})
+    local opts_colored2 = build_component_opts({color = {bg = '#223344'}})
+    local opts_colored3 = build_component_opts({color = {fg = '#223344'}})
+    require'lualine.highlight'.create_highlight_groups(
+        require 'lualine.themes.gruvbox')
+    local section = {
+      require('lua.lualine.components.special.function_component'):new(opts),
+      require('lua.lualine.components.special.function_component'):new(
+          opts_colored),
+      require('lua.lualine.components.special.function_component'):new(opts)
+    }
+    -- Removes separator on string color
+    eq('%#MyHl# test %#MyHl#%#MyColor# test %#MyHl# test ',
+       sec.draw_section(section, '%#MyHl#'))
+    section[2] =
+        require('lua.lualine.components.special.function_component'):new(
+            opts_colored2)
+    local highlight_name =
+        '%#lualine_c_' .. section[2].options.component_name .. '_normal#'
+    -- Removes separator on color with bg
+    eq('%#MyHl# test %#MyHl#' .. highlight_name .. ' test %#MyHl# test ',
+       sec.draw_section(section, '%#MyHl#'))
+    section[2] =
+        require('lua.lualine.components.special.function_component'):new(
+            opts_colored3)
+    local highlight_name2 =
+        '%#lualine_c_' .. section[2].options.component_name .. '_normal#'
+    -- Doesn't remove separator on color without bg
+    eq('%#MyHl# test %#MyHl#' .. highlight_name2 .. ' test %#MyHl# test ',
+       sec.draw_section(section, '%#MyHl#'))
+  end)
+end)