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diff --git a/LICENSE b/LICENSE
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+MIT License
+
+Copyright (c) 2023 David Elentok
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/README.md b/README.md
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+# encrypt.nvim
+
+This is a simple alternative to the "X" command that was removed from Neovim.
+
+Disclaimer: It's probably not the most secure implementation (if such thing is
+even possible) but it gives the ability to edit files that will be stored in
+encrypted on the disk.
+
+## Usage
+
+1. Open a file
+2. Run `:X`
+3. Enter a password
+
+Now the file is encrypted and every time you open it you'll be asked for the
+password.
+
+## Installation
+
+Add the following to your package manager:
+
+```lua
+{ "elentok/encrypt.nvim", opts = {} },
+```
+
+## TODO
+
+- [ ] Store the password in a local scope in the plugin instead of as a buffer
+      variable.
diff --git a/lua/encrypt/decrypt.lua b/lua/encrypt/decrypt.lua
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+++ b/lua/encrypt/decrypt.lua
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+local helpers = require("encrypt.helpers")
+
+---@return string[]
+---@param lines string | string[]
+---@param password string
+local function decrypt_lines(lines, password)
+  return vim.fn.systemlist(
+    "base64 --decode | openssl enc -d -aes-256-cbc -pbkdf2 -salt -in - -out - -k " .. password,
+    lines
+  )
+end
+
+local function decrypt()
+  local password = helpers.getPassword()
+  local encrypted_lines = vim.api.nvim_buf_get_lines(0, 1, -1, false)
+  local decrypted_lines = decrypt_lines(encrypted_lines, password)
+  if vim.v.shell_error ~= 0 then
+    vim.notify("Error decrypting", vim.log.levels.ERROR)
+    return
+  end
+
+  vim.fn.timer_start(0, function()
+    vim.api.nvim_buf_set_lines(0, 0, -1, false, decrypted_lines)
+    vim.bo.modified = false
+  end)
+end
+
+return decrypt
diff --git a/lua/encrypt/encrypt.lua b/lua/encrypt/encrypt.lua
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+++ b/lua/encrypt/encrypt.lua
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+local helpers = require("encrypt.helpers")
+
+---@return string[]
+---@param lines string | string[]
+---@param password string
+local function encrypt_lines(lines, password)
+  return vim.fn.systemlist(
+    "openssl enc -aes-256-cbc -pbkdf2 -salt -in - -out - -k " .. password .. " | base64",
+    lines
+  )
+end
+
+local function encrypt()
+  local password = helpers.getPassword()
+  local buf_lines = vim.api.nvim_buf_get_lines(0, 0, -1, false)
+  local encrypted_lines = encrypt_lines(buf_lines, password)
+
+  table.insert(encrypted_lines, 1, helpers.ENCRYPTED_PREFIX)
+
+  vim.fn.writefile(encrypted_lines, vim.fn.expand("%"))
+  vim.bo.modified = false
+  print("Encrypted " .. vim.fn.expand("%:t"))
+end
+
+return encrypt
diff --git a/lua/encrypt/helpers.lua b/lua/encrypt/helpers.lua
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+++ b/lua/encrypt/helpers.lua
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+---@return string
+local function getPassword()
+  local password = vim.b["password"]
+  if password == nil then
+    password = vim.fn.inputsecret("Enter password: ")
+    vim.b["password"] = password
+  end
+  return password
+end
+
+local ENCRYPTED_PREFIX = "# <<<encrypted>>>"
+
+return { getPassword = getPassword, ENCRYPTED_PREFIX = ENCRYPTED_PREFIX }
diff --git a/lua/encrypt/init.lua b/lua/encrypt/init.lua
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+++ b/lua/encrypt/init.lua
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+local setupBuffer = require("encrypt.setup-buffer")
+local encrypt = require("encrypt.encrypt")
+local decrypt = require("encrypt.decrypt")
+local helpers = require("encrypt.helpers")
+
+local function setup()
+  vim.api.nvim_create_user_command("X", function()
+    setupBuffer()
+    encrypt()
+  end, {})
+
+  vim.api.nvim_create_autocmd({ "BufReadPost" }, {
+    callback = function()
+      local first_line = vim.api.nvim_buf_get_lines(0, 0, 1, false)[1]
+      if first_line == helpers.ENCRYPTED_PREFIX then
+        setupBuffer()
+        decrypt()
+      end
+    end,
+  })
+end
+
+return { setup = setup }
diff --git a/lua/encrypt/setup-buffer.lua b/lua/encrypt/setup-buffer.lua
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+++ b/lua/encrypt/setup-buffer.lua
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+local encrypt = require("encrypt.encrypt")
+
+local function createWriteAutoCmd()
+  if vim.b["encryptionAutoCmd"] ~= nil then
+    return
+  end
+
+  vim.b["encryptionAutoCmd"] = vim.api.nvim_create_autocmd({ "BufWriteCmd" }, {
+    callback = function()
+      if vim.b["encrypted"] ~= true then
+        return
+      end
+
+      encrypt()
+    end,
+  })
+end
+
+local function setupBuffer()
+  -- buftype="acwrite" means save using the BufWriteCmd command
+  vim.bo.buftype = "acwrite"
+  vim.bo.swapfile = false
+  vim.bo.undofile = false
+  vim.b["encrypted"] = true
+  createWriteAutoCmd()
+end
+
+return setupBuffer
diff --git a/lua/stylua.toml b/lua/stylua.toml
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+++ b/lua/stylua.toml
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+indent_type = "Spaces"
+indent_width = 2
+column_width = 100