diff --git a/README.md b/README.md
index 74d3352..45c41d9 100644
--- a/README.md
+++ b/README.md
@@ -148,7 +148,7 @@ require("gopher").setup {
   </summary>
 
   ```vim
-  " Open alternate test file (if _test file does not exist it will create it)
+  " Open alternate test file
   :GoAlt
 
   " Open test file in horizontal split
diff --git a/lua/gopher/alternate.lua b/lua/gopher/alternate.lua
index f283c37..8965d8d 100644
--- a/lua/gopher/alternate.lua
+++ b/lua/gopher/alternate.lua
@@ -1,22 +1,27 @@
-local M = {}
+local alt = {}
 
-function M.is_test_file()
+function alt.is_test_file()
   local file = vim.fn.expand "%"
+
   if #file <= 1 then
     vim.notify("no buffer name", vim.log.levels.ERROR)
     return nil, false, false
   end
+
   local is_test = string.find(file, "_test%.go$")
   local is_source = string.find(file, "%.go$")
+
   return file, (not is_test and is_source), is_test
 end
 
-function M.alternate()
-  local file, is_source, is_test = M.is_test_file()
+function alt.alternate()
+  local file, is_source, is_test = alt.is_test_file()
   if not file then
     return nil
   end
+
   local alt_file = file
+
   if is_test then
     alt_file = string.gsub(file, "_test.go", ".go")
   elseif is_source then
@@ -24,15 +29,16 @@ function M.alternate()
   else
     vim.notify("not a go file", vim.log.levels.ERROR)
   end
+
   return alt_file
 end
 
-function M.switch(bang, cmd)
-  local alt_file = M.alternate()
-  if not vim.fn.filereadable(alt_file) and not vim.fn.bufexists(alt_file) and not bang then
-    vim.notify("couldn't find " .. alt_file, vim.log.levels.ERROR)
-    return
-  elseif #cmd <= 1 then
+function alt.switch(cmd)
+  cmd = cmd or ""
+
+  local alt_file = alt.alternate()
+
+  if #cmd <= 1 then
     local ocmd = "e " .. alt_file
     vim.cmd(ocmd)
   else
@@ -41,4 +47,4 @@ function M.switch(bang, cmd)
   end
 end
 
-return M
+return alt
diff --git a/plugin/gopher.lua b/plugin/gopher.lua
index d4bb682..7144e5a 100644
--- a/plugin/gopher.lua
+++ b/plugin/gopher.lua
@@ -88,13 +88,13 @@ end, "?")
 
 -- :GoAlt
 cmd("GoAlt", function()
-  require("gopher.alternate").switch(true, "")
+  require("gopher.alternate").switch()
 end)
 
 cmd("GoAltV", function()
-  require("gopher.alternate").switch(true, "vsplit")
+  require("gopher.alternate").switch "vsplit"
 end)
 
 cmd("GoAltS", function()
-  require("gopher.alternate").switch(true, "split")
+  require("gopher.alternate").switch "split"
 end)
diff --git a/spec/fixtures/alternate/source_input.go b/spec/fixtures/alternate/source_input.go
new file mode 100644
index 0000000..06ab7d0
--- /dev/null
+++ b/spec/fixtures/alternate/source_input.go
@@ -0,0 +1 @@
+package main
diff --git a/spec/fixtures/alternate/source_output.go b/spec/fixtures/alternate/source_output.go
new file mode 100644
index 0000000..06ab7d0
--- /dev/null
+++ b/spec/fixtures/alternate/source_output.go
@@ -0,0 +1 @@
+package main
diff --git a/spec/fixtures/alternate/test_input.go b/spec/fixtures/alternate/test_input.go
new file mode 100644
index 0000000..06ab7d0
--- /dev/null
+++ b/spec/fixtures/alternate/test_input.go
@@ -0,0 +1 @@
+package main
diff --git a/spec/fixtures/alternate/test_output.go b/spec/fixtures/alternate/test_output.go
new file mode 100644
index 0000000..06ab7d0
--- /dev/null
+++ b/spec/fixtures/alternate/test_output.go
@@ -0,0 +1 @@
+package main
diff --git a/spec/integration/alternate_test.lua b/spec/integration/alternate_test.lua
new file mode 100644
index 0000000..2607968
--- /dev/null
+++ b/spec/integration/alternate_test.lua
@@ -0,0 +1,83 @@
+-- spec/integration/alternate_test.lua
+--
+-- Integration tests for the GoAlt family of commands after removing the
+-- `bang` flag.  The commands now *always* open or create the sibling file.
+--
+-- Conventions match comment/iferr/impl suites: use `t.setup_test()`,
+-- run the Ex-command via `child.cmd`, then `write`, then assertions.
+
+local t = require "spec.testutils"
+local child, T = t.setup "alternate"
+
+-- ── small helpers ────────────────────────────────────────────────────────
+
+---foo.go ⇄ foo_test.go
+local function sibling(path)
+  if path:find "_test%.go$" then
+    return path:gsub("_test%.go$", ".go")
+  else
+    return path:gsub("%.go$", "_test.go")
+  end
+end
+
+---Run <cmd> inside a tmp copy of fixture `name`.
+---@param name string   "source" or "test"
+---@param cmd  string   "GoAlt", "GoAltV", "GoAltS"
+---@return table        rs from t.setup_test (for later cleanup)
+---@return string       absolute sibling path
+local function do_the_test(name, cmd)
+  local rs = t.setup_test("alternate/" .. name, child, { 1, 1 })
+  local alt = sibling(rs.tmp)
+
+  os.remove(alt)
+  child.cmd(cmd)
+  child.cmd "write"
+
+  return rs, alt
+end
+
+T["GoAlt"] = MiniTest.new_set {}
+T["GoAltV"] = MiniTest.new_set {}
+T["GoAltS"] = MiniTest.new_set {}
+
+T["GoAlt"]["creates/opens sibling from source"] = function()
+  local rs, alt = do_the_test("source", "GoAlt")
+
+  t.eq(child.fn.expand "%:p", alt)
+  t.eq(child.fn.filereadable(alt), 0)
+
+  t.cleanup(rs)
+  t.deletefile(alt)
+end
+
+T["GoAlt"]["toggles back when invoked on test file"] = function()
+  local rs, src = do_the_test("test", "GoAlt")
+
+  t.eq(child.fn.expand "%:p", src)
+  t.eq(child.fn.filereadable(src), 0)
+
+  t.cleanup(rs)
+  t.deletefile(src)
+end
+
+T["GoAltV"]["opens sibling in vertical split"] = function()
+  local rs, alt = do_the_test("source", "GoAltV")
+
+  t.eq(#child.api.nvim_list_wins(), 2)
+  t.eq(child.fn.expand "%:p", alt)
+
+  t.cleanup(rs)
+  t.deletefile(alt)
+end
+
+T["GoAltS"]["opens sibling in horizontal split"] = function()
+  local rs, alt = do_the_test("source", "GoAltS")
+
+  t.eq(#child.api.nvim_list_wins(), 2)
+  t.eq(child.fn.expand "%:p", alt)
+
+  t.cleanup(rs)
+  t.deletefile(alt)
+end
+
+return T