diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..7dbe2b3
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,45 @@
+name: Tests
+
+on: [push, pull_request]
+
+jobs:
+  unit_tests:
+    name: unit tests
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-22.04
+            rev: nightly/nvim-linux64.tar.gz
+          - os: ubuntu-22.04
+            rev: v0.9.0/nvim-linux64.tar.gz
+    steps:
+      - uses: actions/checkout@v4
+      - uses: extractions/setup-just@v2
+      - run: date +%F > todays-date
+      - name: Restore from todays cache
+        uses: actions/cache@v3
+        with:
+          path: _neovim
+          key: ${{ runner.os }}-${{ matrix.rev }}-${{ hashFiles('todays-date') }}
+
+      - name: Prepare
+        run: |
+          test -d _neovim || {
+            mkdir -p _neovim
+            curl -sL "https://github.com/neovim/neovim/releases/download/${{ matrix.rev }}" | tar xzf - --strip-components=1 -C "${PWD}/_neovim"
+          }
+      - name: Dependencies
+        run: |
+            git clone --depth 1 https://github.com/nvim-lua/plenary.nvim ~/.local/share/nvim/site/pack/vendor/start/plenary.nvim
+            git clone --depth 1 https://github.com/nvim-treesitter/nvim-treesitter ~/.local/share/nvim/site/pack/vendor/start/nvim-treesitter
+            git clone --depth 1 https://github.com/hrsh7th/nvim-cmp ~/.local/share/nvim/site/pack/vendor/start/nvim-cmp
+            git clone --depth 1 https://github.com/L3MON4D3/LuaSnip ~/.local/share/nvim/site/pack/vendor/start/LuaSnip
+
+            ln -s "$(pwd)" ~/.local/share/nvim/site/pack/vendor/start
+      - name: Run tests
+        run: |
+          export PATH="${PWD}/_neovim/bin:${PATH}"
+          nvim --version
+          just test
diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
new file mode 100644
index 0000000..3939457
--- /dev/null
+++ b/.github/workflows/format.yml
@@ -0,0 +1,26 @@
+name: Format
+
+on: [push, pull_request]
+
+jobs:
+  format:
+    name: Stylua
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - run: date +%W > weekly
+
+      - name: Restore cache
+        id: cache
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cargo/bin
+          key: ${{ runner.os }}-cargo-${{ hashFiles('weekly') }}
+
+      - name: Install
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: cargo install stylua
+
+      - name: Format
+        run: stylua --check lua/ --config-path=stylua.toml
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
new file mode 100644
index 0000000..51fd4b6
--- /dev/null
+++ b/.github/workflows/lint.yml
@@ -0,0 +1,17 @@
+name: Lint
+
+on: [push, pull_request]
+
+jobs:
+  lint:
+    name: Luacheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup
+        run: |
+          sudo apt-get update
+          sudo apt-get install luarocks -y
+          sudo luarocks install luacheck
+      - name: Lint
+        run: luacheck lua/ --globals vim
diff --git a/lua/ledger/completion/cmp.lua b/lua/ledger/completion/cmp.lua
index ea0b6aa..3739e71 100644
--- a/lua/ledger/completion/cmp.lua
+++ b/lua/ledger/completion/cmp.lua
@@ -24,7 +24,7 @@ function M.new()
   return setmetatable({}, LedgerCmp)
 end
 
-function LedgerCmp:is_available()
+function LedgerCmp.is_available()
   return common.is_available()
 end
 
@@ -32,7 +32,7 @@ end
 --- specify
 ---
 ---@return string
-function LedgerCmp:get_debug_name()
+function LedgerCmp.get_debug_name()
   return "ledger.nvim"
 end
 
diff --git a/lua/ledger/diagnostics.lua b/lua/ledger/diagnostics.lua
index 8c75cae..40ac040 100644
--- a/lua/ledger/diagnostics.lua
+++ b/lua/ledger/diagnostics.lua
@@ -22,11 +22,9 @@ function M.get_missing_accounts()
   for filename, postings in pairs(context.postings) do
     for _, posting in pairs(postings) do
       local account_name = posting.account.text
-      local has_commodity = false
 
       for _, accounts in pairs(context.accounts) do
-        has_commodity = vim.tbl_contains(accounts, account_name)
-        if has_commodity then
+        if vim.tbl_contains(accounts, account_name) then
           goto continue
         end
       end
@@ -63,11 +61,9 @@ function M.get_missing_commodities()
       end
 
       local commodity_name = posting.commodity.text
-      local has_commodity = false
 
       for _, commodities in pairs(context.commodities) do
-        has_commodity = vim.tbl_contains(commodities, commodity_name)
-        if has_commodity then
+        if vim.tbl_contains(commodities, commodity_name) then
           goto continue
         end
       end
diff --git a/lua/ledger/logger.lua b/lua/ledger/logger.lua
index 8f4303a..5abbcb1 100644
--- a/lua/ledger/logger.lua
+++ b/lua/ledger/logger.lua
@@ -43,26 +43,26 @@ end
 ---
 --- @param level string
 --- @return string
-function LedgerLogger:get_prefix(level)
+function LedgerLogger.get_prefix(level)
   local timestamp = os.date("%Y-%m-%d %H:%M:%S")
   return "[" .. timestamp .. "] " .. level .. " "
 end
 
 --- @param message string
 function LedgerLogger:info(message)
-  local prefix = self:get_prefix("[INFO]")
+  local prefix = self.get_prefix("[INFO]")
   self:log(prefix .. message .. "\n")
 end
 
 --- @param message string
 function LedgerLogger:error(message)
-  local prefix = self:get_prefix("[ERROR]")
+  local prefix = self.get_prefix("[ERROR]")
   self:log(prefix .. message .. "\n")
 end
 
 --- @param message string
 function LedgerLogger:warn(message)
-  local prefix = self:get_prefix("[WARN]")
+  local prefix = self.get_prefix("[WARN]")
   self:log(prefix .. message .. "\n")
 end
 
diff --git a/lua/ledger/snippets/cmp.lua b/lua/ledger/snippets/cmp.lua
index 20d5ebe..a50a393 100644
--- a/lua/ledger/snippets/cmp.lua
+++ b/lua/ledger/snippets/cmp.lua
@@ -3,9 +3,6 @@ local template_converter = require("ledger.snippets.template_converter")
 --- @class CmpSnippetCompletionSource
 local M = {}
 
-local LedgerSnippetCmpSource = {}
-LedgerSnippetCmpSource.__index = LedgerSnippetCmpSource
-
 --- @param snippets ledger.SnippetList
 --- @return lsp.CompletionItem[]
 function M.new(snippets)