From 972b3e1859fcfe47a55a1095824dc7dafebeb7bb Mon Sep 17 00:00:00 2001
From: Noah Bauer <noah.bauer@exxeta.com>
Date: Thu, 23 Jul 2026 12:54:33 +0200
Subject: [PATCH 1/3] feat: add split before option

---
 README.md                         | 1 +
 lua/sidekick/cli/session/tmux.lua | 3 +++
 lua/sidekick/config.lua           | 1 +
 3 files changed, 5 insertions(+)

diff --git a/README.md b/README.md
index 675ee135..cef78ecd 100644
--- a/README.md
+++ b/README.md
@@ -326,6 +326,7 @@ local defaults = {
       create = "terminal", ---@type "terminal"|"window"|"split"
       split = {
         vertical = true, -- vertical or horizontal split
+        before = false, -- place the split before the current pane (left when vertical, above when horizontal)
         size = 0.5, -- size of the split (0-1 for percentage)
       },
     },
diff --git a/lua/sidekick/cli/session/tmux.lua b/lua/sidekick/cli/session/tmux.lua
index 95dbbb48..9c98ca38 100644
--- a/lua/sidekick/cli/session/tmux.lua
+++ b/lua/sidekick/cli/session/tmux.lua
@@ -44,6 +44,9 @@ function M:start()
   elseif Config.cli.mux.create == "split" then
     local cmd = { "tmux", "split-window", "-dP", "-c", self.cwd, "-F", PANE_FORMAT }
     cmd[#cmd + 1] = Config.cli.mux.split.vertical and "-h" or "-v"
+    if Config.cli.mux.split.before then
+      cmd[#cmd + 1] = "-b"
+    end
     local size = Config.cli.mux.split.size
     vim.list_extend(cmd, { "-l", tostring(size <= 1 and ((size * 100) .. "%") or size) })
     self:add_cmd(cmd)
diff --git a/lua/sidekick/config.lua b/lua/sidekick/config.lua
index d30e92e8..c6a95c8f 100644
--- a/lua/sidekick/config.lua
+++ b/lua/sidekick/config.lua
@@ -93,6 +93,7 @@ local defaults = {
       create = "terminal", ---@type "terminal"|"window"|"split"
       split = {
         vertical = true, -- vertical or horizontal split
+        before = false, -- place the split before the current pane (left when vertical, above when horizontal)
         size = 0.5, -- size of the split (0-1 for percentage)
       },
       -- max lines to capture when dumping a multiplexer pane for scrollback support

From 23164f7c743156781fa09c9bbad3754baf094092 Mon Sep 17 00:00:00 2001
From: Noah Bauer <noah.bauer@exxeta.com>
Date: Thu, 23 Jul 2026 13:04:26 +0200
Subject: [PATCH 2/3] feat: add close_on_exit option

---
 README.md                         |  1 +
 lua/sidekick/cli/session/tmux.lua | 17 +++++++++++++++++
 lua/sidekick/config.lua           |  1 +
 3 files changed, 19 insertions(+)

diff --git a/README.md b/README.md
index cef78ecd..05ce50c6 100644
--- a/README.md
+++ b/README.md
@@ -328,6 +328,7 @@ local defaults = {
         vertical = true, -- vertical or horizontal split
         before = false, -- place the split before the current pane (left when vertical, above when horizontal)
         size = 0.5, -- size of the split (0-1 for percentage)
+        close_on_exit = false, -- close the split when Neovim exits
       },
     },
     --- Actual cli tool config is loaded from the runtime path `sk/cli/{tool}.lua` and merged with the config below.
diff --git a/lua/sidekick/cli/session/tmux.lua b/lua/sidekick/cli/session/tmux.lua
index 9c98ca38..d20c5272 100644
--- a/lua/sidekick/cli/session/tmux.lua
+++ b/lua/sidekick/cli/session/tmux.lua
@@ -51,10 +51,27 @@ function M:start()
     vim.list_extend(cmd, { "-l", tostring(size <= 1 and ((size * 100) .. "%") or size) })
     self:add_cmd(cmd)
     self:spawn(cmd)
+    if Config.cli.mux.split.close_on_exit then
+      self:close_on_exit()
+    end
     Util.info(("Started **%s** in a new tmux split"):format(self.tool.name))
   end
 end
 
+--- Kill the tmux pane when Neovim exits.
+function M:close_on_exit()
+  local pane_id = self.tmux_pane_id
+  if not pane_id then
+    return
+  end
+  vim.api.nvim_create_autocmd("VimLeavePre", {
+    once = true,
+    callback = function()
+      pcall(Util.exec, { "tmux", "kill-pane", "-t", pane_id }, { notify = false })
+    end,
+  })
+end
+
 --- Execute the given tmux command and update the session info,
 --- based on the first pane returned.
 ---@param cmd string[]
diff --git a/lua/sidekick/config.lua b/lua/sidekick/config.lua
index c6a95c8f..a6f1bfb7 100644
--- a/lua/sidekick/config.lua
+++ b/lua/sidekick/config.lua
@@ -95,6 +95,7 @@ local defaults = {
         vertical = true, -- vertical or horizontal split
         before = false, -- place the split before the current pane (left when vertical, above when horizontal)
         size = 0.5, -- size of the split (0-1 for percentage)
+        close_on_exit = false, -- close the split when Neovim exits
       },
       -- max lines to capture when dumping a multiplexer pane for scrollback support
       -- more lines means slower loading of the scrollback

From 26fbb62405350a286ce8ba35686cd72358d9c458 Mon Sep 17 00:00:00 2001
From: Noah Bauer <noah.bauer@exxeta.com>
Date: Thu, 23 Jul 2026 14:26:07 +0200
Subject: [PATCH 3/3] feat: toggle now also toggles tmux splits and also closes
 them on calling the close method (detaching)

---
 lua/sidekick/cli/init.lua         | 34 +++++++++++-----
 lua/sidekick/cli/session/init.lua | 16 ++++++++
 lua/sidekick/cli/session/tmux.lua | 64 +++++++++++++++++++++++++++++++
 lua/sidekick/cli/state.lua        |  1 +
 4 files changed, 106 insertions(+), 9 deletions(-)

diff --git a/lua/sidekick/cli/init.lua b/lua/sidekick/cli/init.lua
index 9c0e9b50..60bf8253 100644
--- a/lua/sidekick/cli/init.lua
+++ b/lua/sidekick/cli/init.lua
@@ -86,7 +86,11 @@ end
 ---@overload fun(name: string)
 function M.show(opts)
   opts = filter_opts(opts)
-  State.with(function() end, {
+  State.with(function(state)
+    if not state.terminal and state.session and not state.session:is_open() then
+      state.session:show()
+    end
+  end, {
     all = opts.all,
     attach = true,
     filter = opts.filter,
@@ -100,14 +104,22 @@ end
 function M.toggle(opts)
   opts = filter_opts(opts)
   State.with(function(state, attached)
-    if not state.terminal then
+    if state.terminal then
+      if not attached then
+        state.terminal:toggle()
+      end
+      if state.terminal:is_open() and opts.focus ~= false then
+        state.terminal:focus()
+      end
       return
     end
-    if not attached then
-      state.terminal:toggle()
-    end
-    if state.terminal:is_open() and opts.focus ~= false then
-      state.terminal:focus()
+    if state.session then
+      local open = state.session:is_open()
+      if open and not attached then
+        state.session:hide()
+      elseif not open then
+        state.session:show()
+      end
     end
   end, {
     attach = true,
@@ -142,10 +154,14 @@ end
 function M.hide(opts)
   opts = filter_opts(opts)
   State.with(function(state)
-    return state.terminal and state.terminal:hide()
+    if state.terminal then
+      return state.terminal:hide()
+    elseif state.session and state.session:is_open() then
+      return state.session:hide()
+    end
   end, {
     all = opts.all,
-    filter = Util.merge(opts.filter, { terminal = true }),
+    filter = opts.filter,
   })
 end
 
diff --git a/lua/sidekick/cli/session/init.lua b/lua/sidekick/cli/session/init.lua
index 1c598924..ebff9e9d 100644
--- a/lua/sidekick/cli/session/init.lua
+++ b/lua/sidekick/cli/session/init.lua
@@ -52,6 +52,22 @@ function B:attach() end
 --- Detach from an existing session
 function B:detach() end
 
+--- Whether the session is currently visible.
+--- Backends without a visibility concept are always considered open.
+---@return boolean
+function B:is_open()
+  return true
+end
+
+--- Hide the session from view without stopping it (optional hook)
+function B:hide() end
+
+--- Stop the session and remove its pane/window (optional hook)
+function B:close() end
+
+--- Bring a hidden session back into view (optional hook)
+function B:show() end
+
 --- Start a new session
 --- If the backend returns a Cmd, a new terminal session will be spawned
 ---@return sidekick.cli.terminal.Cmd?
diff --git a/lua/sidekick/cli/session/tmux.lua b/lua/sidekick/cli/session/tmux.lua
index d20c5272..966f9e71 100644
--- a/lua/sidekick/cli/session/tmux.lua
+++ b/lua/sidekick/cli/session/tmux.lua
@@ -58,6 +58,70 @@ function M:start()
   end
 end
 
+--- Whether the split pane currently lives in Neovim's tmux window.
+--- Hidden panes are broken out into a separate (background) window.
+---@return boolean
+function M:is_open()
+  if Config.cli.mux.create ~= "split" then
+    return true
+  end
+  local pane = self:pane_id()
+  local nvim_pane = vim.env.TMUX_PANE
+  if not pane or not nvim_pane then
+    return true
+  end
+  local windows = {} ---@type table<string, string>
+  local lines = Util.exec({ "tmux", "list-panes", "-a", "-F", "#{pane_id} #{window_id}" }, { notify = false })
+  for _, line in ipairs(lines or {}) do
+    local p, w = line:match("^(%%%d+) (@%d+)$")
+    if p then
+      windows[p] = w
+    end
+  end
+  return windows[pane] ~= nil and windows[pane] == windows[nvim_pane]
+end
+
+--- Hide the split by breaking its pane into a detached background window.
+function M:hide()
+  if Config.cli.mux.create ~= "split" then
+    return
+  end
+  local pane = self:pane_id()
+  if pane then
+    Util.exec({ "tmux", "break-pane", "-d", "-s", pane }, { notify = false })
+  end
+end
+
+--- Show the split by joining its pane back next to Neovim.
+function M:show()
+  if Config.cli.mux.create ~= "split" then
+    return
+  end
+  local pane = self:pane_id()
+  local nvim_pane = vim.env.TMUX_PANE
+  if not pane or not nvim_pane then
+    return
+  end
+  local cmd = { "tmux", "join-pane", "-s", pane, "-t", nvim_pane }
+  cmd[#cmd + 1] = Config.cli.mux.split.vertical and "-h" or "-v"
+  if Config.cli.mux.split.before then
+    cmd[#cmd + 1] = "-b"
+  end
+  local size = Config.cli.mux.split.size
+  vim.list_extend(cmd, { "-l", tostring(size <= 1 and ((size * 100) .. "%") or size) })
+  Util.exec(cmd, { notify = false })
+  -- keep focus on Neovim, matching the detached (`-d`) behavior of a fresh split
+  Util.exec({ "tmux", "select-pane", "-t", nvim_pane }, { notify = false })
+end
+
+--- Close the split/window by killing its tmux pane.
+function M:close()
+  local pane = self.tmux_pane_id
+  if pane then
+    Util.exec({ "tmux", "kill-pane", "-t", pane }, { notify = false })
+  end
+end
+
 --- Kill the tmux pane when Neovim exits.
 function M:close_on_exit()
   local pane_id = self.tmux_pane_id
diff --git a/lua/sidekick/cli/state.lua b/lua/sidekick/cli/state.lua
index 01f1f3e3..1480a13e 100644
--- a/lua/sidekick/cli/state.lua
+++ b/lua/sidekick/cli/state.lua
@@ -206,6 +206,7 @@ function M.detach(state)
     if state.terminal then
       state.terminal:close()
     else
+      state.session:close()
       Session.detach(state.session)
       Util.info("Detached from `" .. state.tool.name .. "`")
     end