My Hammerspoon config

init.lua

--
-- Creates an application hotkey.
--

function bind_hotkey(mods, key, name)
  return hs.hotkey.bind(mods, key, name, function ()
    hs.application.open(name)
  end)
end

--
-- Create application hotkeys.
--

bind_hotkey({"alt", "cmd"}, "§", "iTerm")
bind_hotkey({"alt", "cmd"}, "F1", "Messages")
bind_hotkey({"alt", "cmd"}, "F2", "Textual 7")
bind_hotkey({"alt", "cmd"}, "F3", "Slack")
bind_hotkey({"alt", "cmd"}, "F4", "Discord")
bind_hotkey({"alt", "cmd"}, "F5", "Scrivener")
-- bind_hotkey({"ctrl", "alt", "cmd"}, "/", "Dash")

--
-- Set grid options.
--

grid_margins = hs.geometry.size(5, 5)
grid_size = hs.geometry.size(10, 2)

hs.grid.setGrid(tostring(grid_size.w) .. "x" .. tostring(grid_size.h))
hs.grid.setMargins(grid_margins)

--
-- Moves the focused window to the given grid position.
--

function move_grid_window(dir, col, icon)
  local win = hs.window.focusedWindow()
  if win then
    if col == 0 then
      col = 10
    end
    if dir == "left" then
      hs.grid.set(win, {x=0, y=0, w=col, h=grid_size.h})
      hs.grid.snap(win)
    elseif dir == "right" then
      hs.grid.set(win, {x=grid_size.w-col, y=0, w=col, h=grid_size.h})
      hs.grid.snap(win)
    end
  end
end

--
-- Creates a grid hotkey.
--

function create_grid_hotkey(key, icon)
  local outer_hk = hs.hotkey.modal.new({"ctrl", "alt", "cmd"}, key)
  function outer_hk:entered()
    hs.alert.show("Grid " .. icon)
  end
  outer_hk:bind("", "escape", function()
    hs.alert.show("Cancelled")
    outer_hk:exit()
  end)
  for i = 0, grid_size.w - 1 do
    outer_hk:bind("", tostring(i), function()
      hs.alert.show("Grid " .. tostring(i) .. " " .. icon)
      move_grid_window(key, i, icon)
      outer_hk:exit()
    end)
  end
end

--
-- Create left grid hotkey.
--

create_grid_hotkey("left", "\xE2\xAC\x85")

--
-- Create right grid hotkey.
--

create_grid_hotkey("right", "\xE2\x9E\xA1")

--
-- Set the focused window to upper 50%.
--

up_hk = hs.hotkey.bind({"ctrl", "alt", "cmd"}, "up", function()
  win = hs.window.focusedWindow()
  if win then
    g = hs.grid.get(win)
    g.y = 0
    g.h = 1
    hs.grid.set(win, g)
  end
end)

--
-- Set the focused window to lower 50%.
--

down_hk = hs.hotkey.bind({"ctrl", "alt", "cmd"}, "down", function()
  win = hs.window.focusedWindow()
  if win then
    g = hs.grid.get(win)
    g.y = 1
    g.h = 1
    hs.grid.set(win, g)
  end
end)

--
-- Move the focused window left 1 screen.
--

hs.hotkey.bind({"shift", "ctrl", "alt", "cmd"}, "left", function()
  win = hs.window.focusedWindow()
  if win then
    win:moveOneScreenWest()
  end
end)

--
-- Move the focused window right 1 screen.
--

hs.hotkey.bind({"shift", "ctrl", "alt", "cmd"}, "right", function()
  win = hs.window.focusedWindow()
  if win then
    win:moveOneScreenEast()
  end
end)

--
-- Move the focused window up 1 screen.
--

hs.hotkey.bind({"shift", "ctrl", "alt", "cmd"}, "up", function()
  win = hs.window.focusedWindow()
  if win then
    win:moveOneScreenNorth()
  end
end)

--
-- Move the focused window down 1 screen.
--

hs.hotkey.bind({"shift", "ctrl", "alt", "cmd"}, "down", function()
  win = hs.window.focusedWindow()
  if win then
    win:moveOneScreenSouth()
  end
end)