diff --git a/examples/cli.zig b/examples/cli.zig
index 9a19541..0ec8547 100644
--- a/examples/cli.zig
+++ b/examples/cli.zig
@@ -92,7 +92,7 @@ pub fn main() !void {
                     .text = opt,
                     .style = if (j == i) .{ .reverse = true } else .{},
                 }};
-                _ = win.print(&seg, .{ .row_offset = j + 1 });
+                _ = win.print(&seg, .{ .row_offset = @intCast(j + 1) });
             }
         }
         try vx.render(tty.anyWriter());
diff --git a/examples/image.zig b/examples/image.zig
index 0b05b68..6015457 100644
--- a/examples/image.zig
+++ b/examples/image.zig
@@ -47,7 +47,7 @@ pub fn main() !void {
 
     var n: usize = 0;
 
-    var clip_y: usize = 0;
+    var clip_y: u16 = 0;
 
     while (true) {
         const event = loop.nextEvent();
diff --git a/examples/main.zig b/examples/main.zig
index 4cfeb13..fbf116f 100644
--- a/examples/main.zig
+++ b/examples/main.zig
@@ -67,12 +67,13 @@ pub fn main() !void {
         // the old and only updated cells will be drawn
         win.clear();
 
+        const msg_len: u16 = @intCast(msg.len);
         // Create some child window. .expand means the height and width will
         // fill the remaining space of the parent. Child windows do not store a
         // reference to their parent: this is true immediate mode. Do not store
         // windows, always create new windows each render cycle
         const child = win.child(
-            .{ .x_off = win.width / 2 - msg.len / 2, .y_off = win.height / 2 },
+            .{ .x_off = win.width / 2 - msg_len / 2, .y_off = win.height / 2 },
         );
         // Loop through the message and print the cells to the screen
         for (msg, 0..) |_, i| {
@@ -86,7 +87,7 @@ pub fn main() !void {
                     .fg = .{ .index = color_idx },
                 },
             };
-            child.writeCell(i, 0, cell);
+            child.writeCell(@intCast(i), 0, cell);
         }
         // Render the screen
         try vx.render(tty.anyWriter());
diff --git a/examples/table.zig b/examples/table.zig
index 3259f33..25e623f 100644
--- a/examples/table.zig
+++ b/examples/table.zig
@@ -155,10 +155,10 @@ pub fn main() !void {
                         // Select/Unselect Row
                         if (key.matches(vaxis.Key.space, .{})) {
                             const rows = demo_tbl.sel_rows orelse createRows: {
-                                demo_tbl.sel_rows = try alloc.alloc(usize, 1);
+                                demo_tbl.sel_rows = try alloc.alloc(u16, 1);
                                 break :createRows demo_tbl.sel_rows.?;
                             };
-                            var rows_list = std.ArrayList(usize).fromOwnedSlice(alloc, rows);
+                            var rows_list = std.ArrayList(u16).fromOwnedSlice(alloc, rows);
                             for (rows_list.items, 0..) |row, idx| {
                                 if (row != demo_tbl.row) continue;
                                 _ = rows_list.orderedRemove(idx);
@@ -179,11 +179,11 @@ pub fn main() !void {
                                 mem.eql(u8, ":quit", cmd) or
                                 mem.eql(u8, ":exit", cmd)) return;
                             if (mem.eql(u8, "G", cmd)) {
-                                demo_tbl.row = user_list.items.len - 1;
+                                demo_tbl.row = @intCast(user_list.items.len - 1);
                                 active = .mid;
                             }
                             if (cmd.len >= 2 and mem.eql(u8, "gg", cmd[0..2])) {
-                                const goto_row = fmt.parseInt(usize, cmd[2..], 0) catch 0;
+                                const goto_row = fmt.parseInt(u16, cmd[2..], 0) catch 0;
                                 demo_tbl.row = goto_row;
                                 active = .mid;
                             }
@@ -213,7 +213,7 @@ pub fn main() !void {
             };
             demo_tbl.active_ctx = &row_ctx;
             demo_tbl.active_content_fn = struct {
-                fn see(win: *vaxis.Window, ctx_raw: *const anyopaque) !usize {
+                fn see(win: *vaxis.Window, ctx_raw: *const anyopaque) !u16 {
                     const ctx: *const RowContext = @alignCast(@ptrCast(ctx_raw));
                     win.height = 5;
                     const see_win = win.child(.{
diff --git a/examples/view.zig b/examples/view.zig
index bb85687..89a29da 100644
--- a/examples/view.zig
+++ b/examples/view.zig
@@ -29,10 +29,10 @@ pub fn main() !void {
     var use_sm_map = false;
     var use_mini_view = false;
 
-    var x: usize = 0;
-    var y: usize = 0;
-    var h: usize = 0;
-    var w: usize = 0;
+    var x: u16 = 0;
+    var y: u16 = 0;
+    var h: u16 = 0;
+    var w: u16 = 0;
     defer log.info(
         \\Results:
         \\ - Map Size:    {d}x{d}
@@ -351,11 +351,11 @@ const lg_world_map =
     \\  +SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS+ 
     \\
 ;
-const lg_map_width = mapWidth: {
+const lg_map_width: u16 = mapWidth: {
     @setEvalBranchQuota(100_000);
-    break :mapWidth mem.indexOfScalar(u8, lg_world_map, '\n').?;
+    break :mapWidth @intCast(mem.indexOfScalar(u8, lg_world_map, '\n').?);
 };
-const lg_map_height = mapHeight: {
+const lg_map_height: u16 = mapHeight: {
     @setEvalBranchQuota(100_000);
-    break :mapHeight mem.count(u8, lg_world_map, "\n");
+    break :mapHeight @intCast(mem.count(u8, lg_world_map, "\n"));
 };
diff --git a/src/Image.zig b/src/Image.zig
index 97b1042..85cc711 100644
--- a/src/Image.zig
+++ b/src/Image.zig
@@ -33,8 +33,8 @@ pub const Placement = struct {
 };
 
 pub const CellSize = struct {
-    rows: usize,
-    cols: usize,
+    rows: u16,
+    cols: u16,
 };
 
 pub const DrawOptions = struct {
@@ -42,8 +42,8 @@ pub const DrawOptions = struct {
     /// origin of the image. These must be less than the pixel size of a single
     /// cell
     pixel_offset: ?struct {
-        x: usize,
-        y: usize,
+        x: u16,
+        y: u16,
     } = null,
     /// the vertical stacking order
     /// < 0: Drawn beneath text
@@ -51,10 +51,10 @@ pub const DrawOptions = struct {
     z_index: ?i32 = null,
     /// A clip region of the source image to draw.
     clip_region: ?struct {
-        x: ?usize = null,
-        y: ?usize = null,
-        width: ?usize = null,
-        height: ?usize = null,
+        x: ?u16 = null,
+        y: ?u16 = null,
+        width: ?u16 = null,
+        height: ?u16 = null,
     } = null,
     /// Scaling to apply to the Image
     scale: enum {
@@ -71,8 +71,8 @@ pub const DrawOptions = struct {
     /// field, and should prefer to use scale. `draw` will fill in this field with
     /// the correct values if a scale method is applied.
     size: ?struct {
-        rows: ?usize = null,
-        cols: ?usize = null,
+        rows: ?u16 = null,
+        cols: ?u16 = null,
     } = null,
 };
 
@@ -80,9 +80,9 @@ pub const DrawOptions = struct {
 id: u32,
 
 /// width in pixels
-width: usize,
+width: u16,
 /// height in pixels
-height: usize,
+height: u16,
 
 pub fn draw(self: Image, win: Window, opts: DrawOptions) !void {
     var p_opts = opts;
@@ -176,11 +176,11 @@ pub fn cellSize(self: Image, win: Window) !CellSize {
     const w = win.screen.width;
     const h = win.screen.height;
 
-    const pix_per_col = try std.math.divCeil(usize, x_pix, w);
-    const pix_per_row = try std.math.divCeil(usize, y_pix, h);
+    const pix_per_col = try std.math.divCeil(u16, x_pix, w);
+    const pix_per_row = try std.math.divCeil(u16, y_pix, h);
 
-    const cell_width = std.math.divCeil(usize, self.width, pix_per_col) catch 0;
-    const cell_height = std.math.divCeil(usize, self.height, pix_per_row) catch 0;
+    const cell_width = std.math.divCeil(u16, self.width, pix_per_col) catch 0;
+    const cell_height = std.math.divCeil(u16, self.height, pix_per_row) catch 0;
     return .{
         .rows = cell_height,
         .cols = cell_width,
diff --git a/src/InternalScreen.zig b/src/InternalScreen.zig
index 5d41940..a6e11ee 100644
--- a/src/InternalScreen.zig
+++ b/src/InternalScreen.zig
@@ -32,20 +32,20 @@ pub const InternalCell = struct {
     }
 };
 
-width: usize = 0,
-height: usize = 0,
+width: u16 = 0,
+height: u16 = 0,
 
 buf: []InternalCell = undefined,
 
-cursor_row: usize = 0,
-cursor_col: usize = 0,
+cursor_row: u16 = 0,
+cursor_col: u16 = 0,
 cursor_vis: bool = false,
 cursor_shape: CursorShape = .default,
 
 mouse_shape: MouseShape = .default,
 
 /// sets each cell to the default cell
-pub fn init(alloc: std.mem.Allocator, w: usize, h: usize) !InternalScreen {
+pub fn init(alloc: std.mem.Allocator, w: u16, h: u16) !InternalScreen {
     var screen = InternalScreen{
         .buf = try alloc.alloc(InternalCell, w * h),
     };
@@ -75,8 +75,8 @@ pub fn deinit(self: *InternalScreen, alloc: std.mem.Allocator) void {
 /// writes a cell to a location. 0 indexed
 pub fn writeCell(
     self: *InternalScreen,
-    col: usize,
-    row: usize,
+    col: u16,
+    row: u16,
     cell: Cell,
 ) void {
     if (self.width < col) {
@@ -105,7 +105,7 @@ pub fn writeCell(
     self.buf[i].default = cell.default;
 }
 
-pub fn readCell(self: *InternalScreen, col: usize, row: usize) ?Cell {
+pub fn readCell(self: *InternalScreen, col: u16, row: u16) ?Cell {
     if (self.width < col) {
         // column out of bounds
         return null;
diff --git a/src/Mouse.zig b/src/Mouse.zig
index ca4ac6b..0f62cbf 100644
--- a/src/Mouse.zig
+++ b/src/Mouse.zig
@@ -41,10 +41,10 @@ pub const Type = enum {
     drag,
 };
 
-col: usize,
-row: usize,
-xoffset: usize = 0,
-yoffset: usize = 0,
+col: u16,
+row: u16,
+xoffset: u16 = 0,
+yoffset: u16 = 0,
 button: Button,
 mods: Modifiers,
 type: Type,
diff --git a/src/Parser.zig b/src/Parser.zig
index 767985f..6a481fb 100644
--- a/src/Parser.zig
+++ b/src/Parser.zig
@@ -522,10 +522,10 @@ inline fn parseCsi(input: []const u8, text_buf: []u8) Result {
                 const width_pix = iter.next() orelse "0";
 
                 const winsize: Winsize = .{
-                    .rows = std.fmt.parseUnsigned(usize, height_char, 10) catch return null_event,
-                    .cols = std.fmt.parseUnsigned(usize, width_char, 10) catch return null_event,
-                    .x_pixel = std.fmt.parseUnsigned(usize, width_pix, 10) catch return null_event,
-                    .y_pixel = std.fmt.parseUnsigned(usize, height_pix, 10) catch return null_event,
+                    .rows = std.fmt.parseUnsigned(u16, height_char, 10) catch return null_event,
+                    .cols = std.fmt.parseUnsigned(u16, width_char, 10) catch return null_event,
+                    .x_pixel = std.fmt.parseUnsigned(u16, width_pix, 10) catch return null_event,
+                    .y_pixel = std.fmt.parseUnsigned(u16, height_pix, 10) catch return null_event,
                 };
                 return .{
                     .event = .{ .winsize = winsize },
diff --git a/src/Screen.zig b/src/Screen.zig
index 9282226..6eea1a8 100644
--- a/src/Screen.zig
+++ b/src/Screen.zig
@@ -10,16 +10,16 @@ const Method = @import("gwidth.zig").Method;
 
 const Screen = @This();
 
-width: usize = 0,
-height: usize = 0,
+width: u16 = 0,
+height: u16 = 0,
 
-width_pix: usize = 0,
-height_pix: usize = 0,
+width_pix: u16 = 0,
+height_pix: u16 = 0,
 
 buf: []Cell = undefined,
 
-cursor_row: usize = 0,
-cursor_col: usize = 0,
+cursor_row: u16 = 0,
+cursor_col: u16 = 0,
 cursor_vis: bool = false,
 
 unicode: *const Unicode = undefined,
@@ -49,7 +49,7 @@ pub fn deinit(self: *Screen, alloc: std.mem.Allocator) void {
 }
 
 /// writes a cell to a location. 0 indexed
-pub fn writeCell(self: *Screen, col: usize, row: usize, cell: Cell) void {
+pub fn writeCell(self: *Screen, col: u16, row: u16, cell: Cell) void {
     if (self.width <= col) {
         // column out of bounds
         return;
@@ -63,7 +63,7 @@ pub fn writeCell(self: *Screen, col: usize, row: usize, cell: Cell) void {
     self.buf[i] = cell;
 }
 
-pub fn readCell(self: *const Screen, col: usize, row: usize) ?Cell {
+pub fn readCell(self: *const Screen, col: u16, row: u16) ?Cell {
     if (self.width <= col) {
         // column out of bounds
         return null;
diff --git a/src/Vaxis.zig b/src/Vaxis.zig
index 5a31945..14b77d8 100644
--- a/src/Vaxis.zig
+++ b/src/Vaxis.zig
@@ -23,6 +23,8 @@ const Winsize = @import("main.zig").Winsize;
 const ctlseqs = @import("ctlseqs.zig");
 const gwidth = @import("gwidth.zig");
 
+const assert = std.debug.assert;
+
 const Vaxis = @This();
 
 const log = std.log.scoped(.vaxis);
@@ -84,8 +86,8 @@ state: struct {
     changed_default_fg: bool = false,
     changed_default_bg: bool = false,
     cursor: struct {
-        row: usize = 0,
-        col: usize = 0,
+        row: u16 = 0,
+        col: u16 = 0,
     } = .{},
 } = .{},
 
@@ -139,7 +141,7 @@ pub fn resetState(self: *Vaxis, tty: AnyWriter) !void {
         try self.exitAltScreen(tty);
     } else {
         try tty.writeByte('\r');
-        var i: usize = 0;
+        var i: u16 = 0;
         while (i < self.state.cursor.row) : (i += 1) {
             try tty.writeAll(ctlseqs.ri);
         }
@@ -308,6 +310,8 @@ pub fn queueRefresh(self: *Vaxis) void {
 /// draws the screen to the terminal
 pub fn render(self: *Vaxis, tty: AnyWriter) !void {
     defer self.refresh = false;
+    assert(self.screen.buf.len == self.screen.width * self.screen.height); // correct size
+    assert(self.screen.buf.len == self.screen_last.buf.len); // same size
 
     // Set up sync before we write anything
     // TODO: optimize sync so we only sync _when we have changes_. This
@@ -331,27 +335,27 @@ pub fn render(self: *Vaxis, tty: AnyWriter) !void {
 
     // initialize some variables
     var reposition: bool = false;
-    var row: usize = 0;
-    var col: usize = 0;
+    var row: u16 = 0;
+    var col: u16 = 0;
     var cursor: Style = .{};
     var link: Hyperlink = .{};
     var cursor_pos: struct {
-        row: usize = 0,
-        col: usize = 0,
+        row: u16 = 0,
+        col: u16 = 0,
     } = .{};
 
     // Clear all images
     if (self.caps.kitty_graphics)
         try tty.writeAll(ctlseqs.kitty_graphics_clear);
 
-    var i: usize = 0;
+    var i: u16 = 0;
     while (i < self.screen.buf.len) {
         const cell = self.screen.buf[i];
-        const w = blk: {
+        const w: u16 = blk: {
             if (cell.char.width != 0) break :blk cell.char.width;
 
             const method: gwidth.Method = self.caps.unicode;
-            const width = gwidth.gwidth(cell.char.grapheme, method, &self.unicode.width_data);
+            const width: u16 = @intCast(gwidth.gwidth(cell.char.grapheme, method, &self.unicode.width_data));
             break :blk @max(1, width);
         };
         defer {
@@ -726,8 +730,8 @@ pub fn transmitLocalImagePath(
     allocator: std.mem.Allocator,
     tty: AnyWriter,
     payload: []const u8,
-    width: usize,
-    height: usize,
+    width: u16,
+    height: u16,
     medium: Image.TransmitMedium,
     format: Image.TransmitFormat,
 ) !Image {
@@ -780,8 +784,8 @@ pub fn transmitPreEncodedImage(
     self: *Vaxis,
     tty: AnyWriter,
     bytes: []const u8,
-    width: usize,
-    height: usize,
+    width: u16,
+    height: u16,
     format: Image.TransmitFormat,
 ) !Image {
     defer self.next_img_id += 1;
@@ -861,7 +865,7 @@ pub fn transmitImage(
     const b64_buf = try arena.allocator().alloc(u8, base64Encoder.calcSize(buf.len));
     const encoded = base64Encoder.encode(b64_buf, buf);
 
-    return self.transmitPreEncodedImage(tty, encoded, img.width, img.height, format);
+    return self.transmitPreEncodedImage(tty, encoded, @intCast(img.width), @intCast(img.height), format);
 }
 
 pub fn loadImage(
@@ -961,16 +965,16 @@ pub fn prettyPrint(self: *Vaxis, tty: AnyWriter) !void {
     defer tty.writeAll(ctlseqs.sgr_reset) catch {};
 
     var reposition: bool = false;
-    var row: usize = 0;
-    var col: usize = 0;
+    var row: u16 = 0;
+    var col: u16 = 0;
     var cursor: Style = .{};
     var link: Hyperlink = .{};
     var cursor_pos: struct {
-        row: usize = 0,
-        col: usize = 0,
+        row: u16 = 0,
+        col: u16 = 0,
     } = .{};
 
-    var i: usize = 0;
+    var i: u16 = 0;
     while (i < self.screen.buf.len) {
         const cell = self.screen.buf[i];
         const w = blk: {
diff --git a/src/Window.zig b/src/Window.zig
index ab81fee..dd3d628 100644
--- a/src/Window.zig
+++ b/src/Window.zig
@@ -11,17 +11,17 @@ const Window = @This();
 
 pub const Size = union(enum) {
     expand,
-    limit: usize,
+    limit: u16,
 };
 
 /// horizontal offset from the screen
-x_off: usize,
+x_off: u16,
 /// vertical offset from the screen
-y_off: usize,
+y_off: u16,
 /// width of the window. This can't be larger than the terminal screen
-width: usize,
+width: u16,
 /// height of the window. This can't be larger than the terminal screen
-height: usize,
+height: u16,
 
 screen: *Screen,
 
@@ -30,12 +30,12 @@ screen: *Screen,
 /// unaware of resizes.
 fn initChild(
     self: Window,
-    x_off: usize,
-    y_off: usize,
+    x_off: u16,
+    y_off: u16,
     width: Size,
     height: Size,
 ) Window {
-    const resolved_width = switch (width) {
+    const resolved_width: u16 = switch (width) {
         .expand => self.width -| x_off,
         .limit => |w| blk: {
             if (w + x_off > self.width) {
@@ -44,7 +44,7 @@ fn initChild(
             break :blk w;
         },
     };
-    const resolved_height = switch (height) {
+    const resolved_height: u16 = switch (height) {
         .expand => self.height -| y_off,
         .limit => |h| blk: {
             if (h + y_off > self.height) {
@@ -63,8 +63,8 @@ fn initChild(
 }
 
 pub const ChildOptions = struct {
-    x_off: usize = 0,
-    y_off: usize = 0,
+    x_off: u16 = 0,
+    y_off: u16 = 0,
     /// the width of the resulting child, including any borders
     width: Size = .expand,
     /// the height of the resulting child, including any borders
@@ -141,25 +141,25 @@ pub fn child(self: Window, opts: ChildOptions) Window {
         .other => |loc| loc,
     };
     if (loc.top) {
-        var i: usize = 0;
+        var i: u16 = 0;
         while (i < w) : (i += 1) {
             result.writeCell(i, 0, .{ .char = horizontal, .style = style });
         }
     }
     if (loc.bottom) {
-        var i: usize = 0;
+        var i: u16 = 0;
         while (i < w) : (i += 1) {
             result.writeCell(i, h -| 1, .{ .char = horizontal, .style = style });
         }
     }
     if (loc.left) {
-        var i: usize = 0;
+        var i: u16 = 0;
         while (i < h) : (i += 1) {
             result.writeCell(0, i, .{ .char = vertical, .style = style });
         }
     }
     if (loc.right) {
-        var i: usize = 0;
+        var i: u16 = 0;
         while (i < h) : (i += 1) {
             result.writeCell(w -| 1, i, .{ .char = vertical, .style = style });
         }
@@ -174,24 +174,24 @@ pub fn child(self: Window, opts: ChildOptions) Window {
     if (loc.bottom and loc.right)
         result.writeCell(w -| 1, h -| 1, .{ .char = bottom_right, .style = style });
 
-    const x_off: usize = if (loc.left) 1 else 0;
-    const y_off: usize = if (loc.top) 1 else 0;
-    const h_delt: usize = if (loc.bottom) 1 else 0;
-    const w_delt: usize = if (loc.right) 1 else 0;
-    const h_ch: usize = h -| y_off -| h_delt;
-    const w_ch: usize = w -| x_off -| w_delt;
+    const x_off: u16 = if (loc.left) 1 else 0;
+    const y_off: u16 = if (loc.top) 1 else 0;
+    const h_delt: u16 = if (loc.bottom) 1 else 0;
+    const w_delt: u16 = if (loc.right) 1 else 0;
+    const h_ch: u16 = h -| y_off -| h_delt;
+    const w_ch: u16 = w -| x_off -| w_delt;
     return result.initChild(x_off, y_off, .{ .limit = w_ch }, .{ .limit = h_ch });
 }
 
 /// writes a cell to the location in the window
-pub fn writeCell(self: Window, col: usize, row: usize, cell: Cell) void {
+pub fn writeCell(self: Window, col: u16, row: u16, cell: Cell) void {
     if (self.height == 0 or self.width == 0) return;
     if (self.height <= row or self.width <= col) return;
     self.screen.writeCell(col + self.x_off, row + self.y_off, cell);
 }
 
 /// reads a cell at the location in the window
-pub fn readCell(self: Window, col: usize, row: usize) ?Cell {
+pub fn readCell(self: Window, col: u16, row: u16) ?Cell {
     if (self.height == 0 or self.width == 0) return null;
     if (self.height <= row or self.width <= col) return null;
     return self.screen.readCell(col + self.x_off, row + self.y_off);
@@ -203,7 +203,7 @@ pub fn clear(self: Window) void {
 }
 
 /// returns the width of the grapheme. This depends on the terminal capabilities
-pub fn gwidth(self: Window, str: []const u8) usize {
+pub fn gwidth(self: Window, str: []const u8) u16 {
     return gw.gwidth(str, self.screen.width_method, &self.screen.unicode.width_data);
 }
 
@@ -220,7 +220,7 @@ pub fn fill(self: Window, cell: Cell) void {
         @memset(self.screen.buf[start..end], cell);
     } else {
         // Non-contiguous. Iterate over rows an memset
-        var row: usize = self.y_off;
+        var row: u16 = self.y_off;
         const last_row = @min(self.height + self.y_off, self.screen.height);
         while (row < last_row) : (row += 1) {
             const start = @min(self.x_off + (row * self.screen.width), self.screen.buf.len);
@@ -237,7 +237,7 @@ pub fn hideCursor(self: Window) void {
 }
 
 /// show the cursor at the given coordinates, 0 indexed
-pub fn showCursor(self: Window, col: usize, row: usize) void {
+pub fn showCursor(self: Window, col: u16, row: u16) void {
     if (self.height == 0 or self.width == 0) return;
     if (self.height <= row or self.width <= col) return;
     self.screen.cursor_vis = true;
@@ -252,9 +252,9 @@ pub fn setCursorShape(self: Window, shape: Cell.CursorShape) void {
 /// Options to use when printing Segments to a window
 pub const PrintOptions = struct {
     /// vertical offset to start printing at
-    row_offset: usize = 0,
+    row_offset: u16 = 0,
     /// horizontal offset to start printing at
-    col_offset: usize = 0,
+    col_offset: u16 = 0,
 
     /// wrap behavior for printing
     wrap: enum {
@@ -273,8 +273,8 @@ pub const PrintOptions = struct {
 };
 
 pub const PrintResult = struct {
-    col: usize,
-    row: usize,
+    col: u16,
+    row: u16,
     overflow: bool,
 };
 
@@ -284,7 +284,7 @@ pub fn print(self: Window, segments: []const Segment, opts: PrintOptions) PrintR
     var row = opts.row_offset;
     switch (opts.wrap) {
         .grapheme => {
-            var col: usize = opts.col_offset;
+            var col: u16 = opts.col_offset;
             const overflow: bool = blk: for (segments) |segment| {
                 var iter = self.screen.unicode.graphemeIterator(segment.text);
                 while (iter.next()) |grapheme| {
@@ -324,7 +324,7 @@ pub fn print(self: Window, segments: []const Segment, opts: PrintOptions) PrintR
             };
         },
         .word => {
-            var col: usize = opts.col_offset;
+            var col: u16 = opts.col_offset;
             var overflow: bool = false;
             var soft_wrapped: bool = false;
             outer: for (segments) |segment| {
@@ -406,7 +406,7 @@ pub fn print(self: Window, segments: []const Segment, opts: PrintOptions) PrintR
             };
         },
         .none => {
-            var col: usize = opts.col_offset;
+            var col: u16 = opts.col_offset;
             const overflow: bool = blk: for (segments) |segment| {
                 var iter = self.screen.unicode.graphemeIterator(segment.text);
                 while (iter.next()) |grapheme| {
@@ -443,7 +443,7 @@ pub fn printSegment(self: Window, segment: Segment, opts: PrintOptions) PrintRes
 
 /// scrolls the window down one row (IE inserts a blank row at the bottom of the
 /// screen and shifts all rows up one)
-pub fn scroll(self: Window, n: usize) void {
+pub fn scroll(self: Window, n: u16) void {
     if (n > self.height) return;
     var row = self.y_off;
     while (row < self.height - n) : (row += 1) {
diff --git a/src/gwidth.zig b/src/gwidth.zig
index 2e3ca7d..5f7ffdd 100644
--- a/src/gwidth.zig
+++ b/src/gwidth.zig
@@ -12,30 +12,29 @@ pub const Method = enum {
 };
 
 /// returns the width of the provided string, as measured by the method chosen
-pub fn gwidth(str: []const u8, method: Method, data: *const DisplayWidth.DisplayWidthData) usize {
+pub fn gwidth(str: []const u8, method: Method, data: *const DisplayWidth.DisplayWidthData) u16 {
     switch (method) {
         .unicode => {
             const dw: DisplayWidth = .{ .data = data };
-            return dw.strWidth(str);
+            return @intCast(dw.strWidth(str));
         },
         .wcwidth => {
-            var total: usize = 0;
+            var total: u16 = 0;
             var iter: code_point.Iterator = .{ .bytes = str };
             while (iter.next()) |cp| {
-                const w = switch (cp.code) {
+                const w: u16 = switch (cp.code) {
                     // undo an override in zg for emoji skintone selectors
                     0x1f3fb...0x1f3ff,
                     => 2,
-                    else => data.codePointWidth(cp.code),
+                    else => @max(0, data.codePointWidth(cp.code)),
                 };
-                if (w < 0) continue;
-                total += @intCast(w);
+                total += w;
             }
             return total;
         },
         .no_zwj => {
             var iter = std.mem.split(u8, str, "\u{200D}");
-            var result: usize = 0;
+            var result: u16 = 0;
             while (iter.next()) |s| {
                 result += gwidth(s, .unicode, data);
             }
diff --git a/src/main.zig b/src/main.zig
index 855bd91..c3bfa35 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -39,10 +39,10 @@ pub const Tty = switch (builtin.os.tag) {
 
 /// The size of the terminal screen
 pub const Winsize = struct {
-    rows: usize,
-    cols: usize,
-    x_pixel: usize,
-    y_pixel: usize,
+    rows: u16,
+    cols: u16,
+    x_pixel: u16,
+    y_pixel: u16,
 };
 
 /// Initialize a Vaxis application.
diff --git a/src/widgets/CodeView.zig b/src/widgets/CodeView.zig
index ce7d07b..bb6bbbb 100644
--- a/src/widgets/CodeView.zig
+++ b/src/widgets/CodeView.zig
@@ -4,9 +4,9 @@ const ScrollView = vaxis.widgets.ScrollView;
 const LineNumbers = vaxis.widgets.LineNumbers;
 
 pub const DrawOptions = struct {
-    highlighted_line: usize = 0,
+    highlighted_line: u16 = 0,
     draw_line_numbers: bool = true,
-    indentation: usize = 0,
+    indentation: u16 = 0,
 };
 
 pub const Buffer = vaxis.widgets.TextView.Buffer;
diff --git a/src/widgets/LineNumbers.zig b/src/widgets/LineNumbers.zig
index d076f12..1258d38 100644
--- a/src/widgets/LineNumbers.zig
+++ b/src/widgets/LineNumbers.zig
@@ -12,7 +12,7 @@ pub fn extractDigit(v: usize, n: usize) usize {
     return (v / (std.math.powi(usize, 10, n) catch unreachable)) % 10;
 }
 
-pub fn numDigits(v: usize) usize {
+pub fn numDigits(v: usize) u8 {
     return switch (v) {
         0...9 => 1,
         10...99 => 2,
diff --git a/src/widgets/Table.zig b/src/widgets/Table.zig
index 47df018..5fdcfdb 100644
--- a/src/widgets/Table.zig
+++ b/src/widgets/Table.zig
@@ -9,25 +9,25 @@ const vaxis = @import("../main.zig");
 /// Table Context for maintaining state and drawing Tables with `drawTable()`.
 pub const TableContext = struct {
     /// Current active Row of the Table.
-    row: usize = 0,
+    row: u16 = 0,
     /// Current active Column of the Table.
-    col: usize = 0,
+    col: u16 = 0,
     /// Starting point within the Data List.
-    start: usize = 0,
+    start: u16 = 0,
     /// Selected Rows.
-    sel_rows: ?[]usize = null,
+    sel_rows: ?[]u16 = null,
 
     /// Active status of the Table.
     active: bool = false,
     /// Active Content Callback Function.
     /// If available, this will be called to vertically expand the active row with additional info.
-    active_content_fn: ?*const fn (*vaxis.Window, *const anyopaque) anyerror!usize = null,
+    active_content_fn: ?*const fn (*vaxis.Window, *const anyopaque) anyerror!u16 = null,
     /// Active Content Context
     /// This will be provided to the `active_content` callback when called.
     active_ctx: *const anyopaque = &{},
     /// Y Offset for rows beyond the Active Content.
     /// (This will be calculated automatically)
-    active_y_off: usize = 0,
+    active_y_off: u16 = 0,
 
     /// The Background Color for Selected Rows.
     selected_bg: vaxis.Cell.Color,
@@ -47,9 +47,9 @@ pub const TableContext = struct {
     row_bg_2: vaxis.Cell.Color = .{ .rgb = [_]u8{ 8, 8, 8 } },
 
     /// Y Offset for drawing to the parent Window.
-    y_off: usize = 0,
+    y_off: u16 = 0,
     /// X Offset for printing each Cell/Item.
-    cell_x_off: usize = 1,
+    cell_x_off: u16 = 1,
 
     /// Column Width
     /// Note, if this is left `null` the Column Width will be dynamically calculated during `drawTable()`.
@@ -78,11 +78,11 @@ pub const WidthStyle = union(enum) {
     /// Dynamically calculate Column Widths such that the entire (or most) of the screen is filled horizontally.
     dynamic_fill,
     /// Dynamically calculate the Column Width for each Column based on its Header Length and the provided Padding length.
-    dynamic_header_len: usize,
+    dynamic_header_len: u16,
     /// Statically set all Column Widths to the same value.
-    static_all: usize,
+    static_all: u16,
     /// Statically set individual Column Widths to specific values.
-    static_individual: []const usize,
+    static_individual: []const u16,
 };
 
 /// Column Indexes
@@ -216,11 +216,11 @@ pub fn drawTable(
     });
 
     // Headers
-    if (table_ctx.col > headers.len - 1) table_ctx.col = headers.len - 1;
-    var col_start: usize = 0;
+    if (table_ctx.col > headers.len - 1) table_ctx.col = @intCast(headers.len - 1);
+    var col_start: u16 = 0;
     for (headers[0..], 0..) |hdr_txt, idx| {
         const col_width = try calcColWidth(
-            idx,
+            @intCast(idx),
             headers,
             table_ctx.col_width,
             table_win,
@@ -260,19 +260,19 @@ pub fn drawTable(
 
     // Rows
     if (table_ctx.active_content_fn == null) table_ctx.active_y_off = 0;
-    const max_items =
-        if (data_items.len > table_win.height -| 1) table_win.height -| 1 else data_items.len;
+    const max_items: u16 =
+        if (data_items.len > table_win.height -| 1) table_win.height -| 1 else @intCast(data_items.len);
     var end = table_ctx.start + max_items;
     if (table_ctx.row + table_ctx.active_y_off >= win.height -| 2)
         end -|= table_ctx.active_y_off;
-    if (end > data_items.len) end = data_items.len;
+    if (end > data_items.len) end = @intCast(data_items.len);
     table_ctx.start = tableStart: {
         if (table_ctx.row == 0)
             break :tableStart 0;
         if (table_ctx.row < table_ctx.start)
             break :tableStart table_ctx.start - (table_ctx.start - table_ctx.row);
         if (table_ctx.row >= data_items.len - 1)
-            table_ctx.row = data_items.len - 1;
+            table_ctx.row = @intCast(data_items.len - 1);
         if (table_ctx.row >= end)
             break :tableStart table_ctx.start + (table_ctx.row - end + 1);
         break :tableStart table_ctx.start;
@@ -280,7 +280,7 @@ pub fn drawTable(
     end = table_ctx.start + max_items;
     if (table_ctx.row + table_ctx.active_y_off >= win.height -| 2)
         end -|= table_ctx.active_y_off;
-    if (end > data_items.len) end = data_items.len;
+    if (end > data_items.len) end = @intCast(data_items.len);
     table_ctx.start = @min(table_ctx.start, end);
     table_ctx.active_y_off = 0;
     for (data_items[table_ctx.start..end], 0..) |data, row| {
@@ -288,7 +288,7 @@ pub fn drawTable(
             if (table_ctx.active and table_ctx.start + row == table_ctx.row)
                 break :rowColors .{ table_ctx.active_fg, table_ctx.active_bg };
             if (table_ctx.sel_rows) |rows| {
-                if (mem.indexOfScalar(usize, rows, table_ctx.start + row) != null)
+                if (mem.indexOfScalar(u16, rows, @intCast(table_ctx.start + row)) != null)
                     break :rowColors .{ table_ctx.selected_fg, table_ctx.selected_bg };
             }
             if (row % 2 == 0) break :rowColors .{ .default, table_ctx.row_bg_1 };
@@ -296,7 +296,7 @@ pub fn drawTable(
         };
         var row_win = table_win.child(.{
             .x_off = 0,
-            .y_off = 1 + row + table_ctx.active_y_off,
+            .y_off = @intCast(1 + row + table_ctx.active_y_off),
             .width = .{ .limit = table_win.width },
             .height = .{ .limit = 1 },
             //.border = .{ .where = if (table_ctx.row_borders) .top else .none },
@@ -386,21 +386,21 @@ pub fn drawTable(
 
 /// Calculate the Column Width of `col` using the provided Number of Headers (`num_hdrs`), Width Style (`style`), and Table Window (`table_win`).
 pub fn calcColWidth(
-    col: usize,
+    col: u16,
     headers: []const []const u8,
     style: WidthStyle,
     table_win: vaxis.Window,
-) !usize {
+) !u16 {
     return switch (style) {
         .dynamic_fill => dynFill: {
-            var cw = table_win.width / headers.len;
+            var cw: u16 = table_win.width / @as(u16, @intCast(headers.len));
             if (cw % 2 != 0) cw +|= 1;
             while (cw * headers.len < table_win.width - 1) cw +|= 1;
             break :dynFill cw;
         },
         .dynamic_header_len => dynHdrs: {
             if (col >= headers.len) break :dynHdrs error.NotEnoughStaticWidthsProvided;
-            break :dynHdrs headers[col].len + (style.dynamic_header_len * 2);
+            break :dynHdrs @as(u16, @intCast(headers[col].len)) + (style.dynamic_header_len * 2);
         },
         .static_all => style.static_all,
         .static_individual => statInd: {
diff --git a/src/widgets/TextInput.zig b/src/widgets/TextInput.zig
index c94d86f..ad67c66 100644
--- a/src/widgets/TextInput.zig
+++ b/src/widgets/TextInput.zig
@@ -18,13 +18,13 @@ const ellipsis: Cell.Character = .{ .grapheme = "…", .width = 1 };
 buf: Buffer,
 
 /// the number of graphemes to skip when drawing. Used for horizontal scrolling
-draw_offset: usize = 0,
+draw_offset: u16 = 0,
 /// the column we placed the cursor the last time we drew
-prev_cursor_col: usize = 0,
+prev_cursor_col: u16 = 0,
 /// the grapheme index of the cursor the last time we drew
-prev_cursor_idx: usize = 0,
+prev_cursor_idx: u16 = 0,
 /// approximate distance from an edge before we scroll
-scroll_offset: usize = 4,
+scroll_offset: u16 = 4,
 
 unicode: *const Unicode,
 
@@ -88,8 +88,8 @@ pub fn sliceToCursor(self: *TextInput, buf: []u8) []const u8 {
 }
 
 /// calculates the display width from the draw_offset to the cursor
-pub fn widthToCursor(self: *TextInput, win: Window) usize {
-    var width: usize = 0;
+pub fn widthToCursor(self: *TextInput, win: Window) u16 {
+    var width: u16 = 0;
     const first_half = self.buf.firstHalf();
     var first_iter = self.unicode.graphemeIterator(first_half);
     var i: usize = 0;
@@ -120,10 +120,10 @@ pub fn cursorRight(self: *TextInput) void {
     self.buf.moveGapRight(grapheme.len);
 }
 
-pub fn graphemesBeforeCursor(self: *const TextInput) usize {
+pub fn graphemesBeforeCursor(self: *const TextInput) u16 {
     const first_half = self.buf.firstHalf();
     var first_iter = self.unicode.graphemeIterator(first_half);
-    var i: usize = 0;
+    var i: u16 = 0;
     while (first_iter.next()) |_| {
         i += 1;
     }
@@ -153,8 +153,8 @@ pub fn drawWithStyle(self: *TextInput, win: Window, style: Cell.Style) void {
     // one way to _ensure_ this is to move the gap... but that's a cost we probably don't want to pay.
     const first_half = self.buf.firstHalf();
     var first_iter = self.unicode.graphemeIterator(first_half);
-    var col: usize = 0;
-    var i: usize = 0;
+    var col: u16 = 0;
+    var i: u16 = 0;
     while (first_iter.next()) |grapheme| {
         if (i < self.draw_offset) {
             i += 1;
diff --git a/src/widgets/View.zig b/src/widgets/View.zig
index 7ecb6fc..e068ef6 100644
--- a/src/widgets/View.zig
+++ b/src/widgets/View.zig
@@ -20,8 +20,8 @@ screen: Screen,
 
 /// View Initialization Config
 pub const Config = struct {
-    width: usize,
-    height: usize,
+    width: u16,
+    height: u16,
 };
 
 /// Initialize a new View
@@ -58,8 +58,8 @@ pub fn deinit(self: *View) void {
 }
 
 pub const DrawOptions = struct {
-    x_off: usize = 0,
-    y_off: usize = 0,
+    x_off: u16 = 0,
+    y_off: u16 = 0,
 };
 
 pub fn draw(self: *View, win: Window, opts: DrawOptions) void {
@@ -80,20 +80,20 @@ pub fn draw(self: *View, win: Window, opts: DrawOptions) void {
 
 /// Render Config for `toWin()`
 pub const RenderConfig = struct {
-    x: usize = 0,
-    y: usize = 0,
+    x: u16 = 0,
+    y: u16 = 0,
     width: Extent = .fit,
     height: Extent = .fit,
 
     pub const Extent = union(enum) {
         fit,
-        max: usize,
+        max: u16,
     };
 };
 
 /// Render a portion of this View to the provided Window (`win`).
 /// This will return the bounded X (col), Y (row) coordinates based on the rendering.
-pub fn toWin(self: *View, win: Window, config: RenderConfig) !struct { usize, usize } {
+pub fn toWin(self: *View, win: Window, config: RenderConfig) !struct { u16, u16 } {
     var x = @min(self.screen.width - 1, config.x);
     var y = @min(self.screen.height - 1, config.y);
     const width = width: {
@@ -123,12 +123,12 @@ pub fn toWin(self: *View, win: Window, config: RenderConfig) !struct { usize, us
 }
 
 /// Writes a cell to the location in the View
-pub fn writeCell(self: *View, col: usize, row: usize, cell: Cell) void {
+pub fn writeCell(self: *View, col: u16, row: u16, cell: Cell) void {
     self.screen.writeCell(col, row, cell);
 }
 
 /// Reads a cell at the location in the View
-pub fn readCell(self: *const View, col: usize, row: usize) ?Cell {
+pub fn readCell(self: *const View, col: u16, row: u16) ?Cell {
     return self.screen.readCell(col, row);
 }
 
@@ -138,7 +138,7 @@ pub fn clear(self: View) void {
 }
 
 /// Returns the width of the grapheme. This depends on the terminal capabilities
-pub fn gwidth(self: View, str: []const u8) usize {
+pub fn gwidth(self: View, str: []const u8) u16 {
     return gw.gwidth(str, self.screen.width_method, &self.screen.unicode.width_data);
 }
 
diff --git a/src/widgets/alignment.zig b/src/widgets/alignment.zig
index 0aa7de0..f3c90e9 100644
--- a/src/widgets/alignment.zig
+++ b/src/widgets/alignment.zig
@@ -1,6 +1,6 @@
 const Window = @import("../Window.zig");
 
-pub fn center(parent: Window, cols: usize, rows: usize) Window {
+pub fn center(parent: Window, cols: u16, rows: u16) Window {
     const y_off = (parent.height / 2) -| (rows / 2);
     const x_off = (parent.width / 2) -| (cols / 2);
     return parent.child(.{
diff --git a/src/widgets/terminal/Screen.zig b/src/widgets/terminal/Screen.zig
index 6afdbb2..9bc0aeb 100644
--- a/src/widgets/terminal/Screen.zig
+++ b/src/widgets/terminal/Screen.zig
@@ -49,8 +49,8 @@ pub const Cursor = struct {
     style: vaxis.Style = .{},
     uri: std.ArrayList(u8) = undefined,
     uri_id: std.ArrayList(u8) = undefined,
-    col: usize = 0,
-    row: usize = 0,
+    col: u16 = 0,
+    row: u16 = 0,
     pending_wrap: bool = false,
     shape: vaxis.Cell.CursorShape = .default,
     visible: bool = true,
@@ -68,10 +68,10 @@ pub const Cursor = struct {
 };
 
 pub const ScrollingRegion = struct {
-    top: usize,
-    bottom: usize,
-    left: usize,
-    right: usize,
+    top: u16,
+    bottom: u16,
+    left: u16,
+    right: u16,
 
     pub fn contains(self: ScrollingRegion, col: usize, row: usize) bool {
         return col >= self.left and
@@ -81,8 +81,8 @@ pub const ScrollingRegion = struct {
     }
 };
 
-width: usize = 0,
-height: usize = 0,
+width: u16 = 0,
+height: u16 = 0,
 
 scrolling_region: ScrollingRegion,
 
@@ -93,7 +93,7 @@ cursor: Cursor = .{},
 csi_u_flags: vaxis.Key.KittyFlags = @bitCast(@as(u5, 0)),
 
 /// sets each cell to the default cell
-pub fn init(alloc: std.mem.Allocator, w: usize, h: usize) !Screen {
+pub fn init(alloc: std.mem.Allocator, w: u16, h: u16) !Screen {
     var screen = Screen{
         .buf = try alloc.alloc(Cell, w * h),
         .scrolling_region = .{
@@ -313,7 +313,7 @@ pub fn sgr(self: *Screen, seq: ansi.CSI) void {
     }
 }
 
-pub fn cursorUp(self: *Screen, n: usize) void {
+pub fn cursorUp(self: *Screen, n: u16) void {
     self.cursor.pending_wrap = false;
     if (self.withinScrollingRegion())
         self.cursor.row = @max(
@@ -324,7 +324,7 @@ pub fn cursorUp(self: *Screen, n: usize) void {
         self.cursor.row -|= n;
 }
 
-pub fn cursorLeft(self: *Screen, n: usize) void {
+pub fn cursorLeft(self: *Screen, n: u16) void {
     self.cursor.pending_wrap = false;
     if (self.withinScrollingRegion())
         self.cursor.col = @max(
@@ -335,7 +335,7 @@ pub fn cursorLeft(self: *Screen, n: usize) void {
         self.cursor.col = self.cursor.col -| n;
 }
 
-pub fn cursorRight(self: *Screen, n: usize) void {
+pub fn cursorRight(self: *Screen, n: u16) void {
     self.cursor.pending_wrap = false;
     if (self.withinScrollingRegion())
         self.cursor.col = @min(
diff --git a/src/widgets/terminal/Terminal.zig b/src/widgets/terminal/Terminal.zig
index 67c40fe..07d9ba9 100644
--- a/src/widgets/terminal/Terminal.zig
+++ b/src/widgets/terminal/Terminal.zig
@@ -31,7 +31,7 @@ const posix = std.posix;
 const log = std.log.scoped(.terminal);
 
 pub const Options = struct {
-    scrollback_size: usize = 500,
+    scrollback_size: u16 = 500,
     winsize: Winsize = .{ .rows = 24, .cols = 80, .x_pixel = 0, .y_pixel = 0 },
     initial_working_directory: ?[]const u8 = null,
 };
@@ -52,7 +52,7 @@ pub var global_vts: ?std.AutoHashMap(i32, *Terminal) = null;
 pub var global_sigchild_installed: bool = false;
 
 allocator: std.mem.Allocator,
-scrollback_size: usize,
+scrollback_size: u16,
 
 pty: Pty,
 cmd: Command,
@@ -221,9 +221,9 @@ pub fn draw(self: *Terminal, win: vaxis.Window) !void {
         }
     }
 
-    var row: usize = 0;
+    var row: u16 = 0;
     while (row < self.front_screen.height) : (row += 1) {
-        var col: usize = 0;
+        var col: u16 = 0;
         while (col < self.front_screen.width) {
             const cell = self.front_screen.readCell(col, row) orelse continue;
             win.writeCell(col, row, cell);