From the maker of ttkbootstrap.

bootstack is a batteries-included desktop framework for Python, built on Tk.

60+ themed widgets. Reactive state. Declarative layout. Built-in icons and localization. A CLI that scaffolds, builds, and ships. Everything ttkbootstrap was missing.

Active alpha. APIs may change before the first stable release. See the documentation for guides and the API reference.

Installation

Requires Python 3.12+.

bootstack is currently in active alpha, so the --pre flag is required to opt in to pre-release versions:

pip install --pre bootstack

See it

The widget gallery is a single-window tour of everything bootstack ships — every widget, theme switcher, accent variants, and layout containers. Fastest way to see the framework in action without writing a line of code:

bootstack gallery

Quick Start

import bootstack as bs

app = bs.App(title="Hello bootstack", theme="bootstrap-light")

bs.Label(app, text="Hello from bootstack!").pack(pady=10)
bs.Button(app, text="Primary", accent="primary").pack(pady=5)
bs.Button(app, text="Success", accent="success").pack(pady=5)
bs.Button(app, text="Danger Outline", accent="danger", variant="outline").pack(pady=5)

app.mainloop()

For navigation-based apps, use AppShell — it gives you a toolbar, sidebar, and page stack in one call:

import bootstack as bs

shell = bs.AppShell(title="My App", size=(1000, 650))

home = shell.add_page("home", text="Home", icon="house")
bs.Label(home, text="Welcome!").pack(padx=20, pady=20)

docs = shell.add_page("docs", text="Documents", icon="file-earmark-text")
bs.Label(docs, text="Your documents.").pack(padx=20, pady=20)

shell.mainloop()

How it works

Layout containers

PackFrame and GridFrame let you describe a layout once instead of repeating geometry calls on each child:

form = bs.GridFrame(app, columns=["auto", 1], gap=(12, 6), sticky_items="ew", padding=12)
form.pack(fill="both", expand=True)

bs.Label(form, text="Name").grid()
bs.TextEntry(form).grid()
bs.Label(form, text="Email").grid()
bs.TextEntry(form).grid()
bs.Button(form, text="Submit", accent="primary").grid(columnspan=2)

Semantic styling

Widgets take an accent (color intent) and variant (visual weight) instead of hard-coded colors, so the same code looks right across themes and light/dark modes:

bs.Button(app, text="Save", accent="primary")                       # solid (default)
bs.Button(app, text="Cancel", accent="secondary", variant="outline")
bs.Label(app, text="Heading", font="heading-lg")

Signals (optional)

Plain callbacks work fine for most things. When state needs to flow between widgets, signals give you a small subscribe/get/set primitive:

counter = bs.Signal(0)

label = bs.Label(app)
counter.subscribe(lambda v: label.configure(text=f"Count: {v}"))

bs.Button(app, text="+1", command=lambda: counter.set(counter.get() + 1))

Features

• Application scaffolding — App for blank windows, AppShell for toolbar + sidebar + page-stack apps, undecorated windows with custom chrome
• 60+ themed widgets — ttk-derived primitives plus higher-level composites (TableView, Calendar, DateEntry, Form, FloodGauge, Meter, ToggleGroup, PageStack, Toast, Tooltip, and more)
• 9 dialogs — Message, Query, ColorChooser, ColorDropper, DateDialog, FontDialog, FilterDialog, FormDialog, plus a Dialog base
• Layout containers — PackFrame and GridFrame for declarative layouts; ScrollView, PanedWindow, Accordion, Card, Expander
• Design system — semantic accent colors (primary, secondary, success, danger, warning, info) and variant tokens (solid, outline, ghost, link, text), consistent across widgets
• Built-in themes — paired light/dark variants (amber, aurora, bootstrap, classic, docs, forest, ocean, rose) with runtime theme switching and a custom-theme API
• Reactive signals — observable state with subscribe/get/set, integrates with widgets via signal= / textvariable=
• Forms & validation — Form and Field with built-in validators
• DataSource — common interface over in-memory, SQLite, and file backends, with pagination, filtering, sorting, CRUD, and CSV export
• Localization (i18n) — 23 bundled message catalogs, locale-aware number/date/time formatting via Babel, runtime language switching
• Icons & images — icon handling with theme-aware recoloring, DPI scaling, and caching
• Platform support — DPI awareness, multi-monitor centering, mica/acrylic effects on Windows
• CLI (bootstack) — project scaffolding, run, add components, theme/i18n setup, doctor, build/package

Widget Categories

Category	Widgets
Actions	Button, ButtonGroup, MenuButton, DropdownButton, ContextMenu
Inputs	TextEntry, PasswordEntry, PathEntry, NumericEntry, SpinnerEntry, Scale, ScrolledText, DateEntry, TimeEntry
Selection	CheckButton, CheckToggle, RadioButton, RadioToggle, RadioGroup, ToggleGroup, OptionMenu, SelectBox, Calendar, Switch
Data Display	Label, Badge, ListView, TreeView, TableView, Progressbar, Meter, FloodGauge
Layout	Frame, PackFrame, GridFrame, LabelFrame, PanedWindow, ScrollView, Accordion, Card, Expander, Separator, SizeGrip
Navigation	AppShell, Toolbar, SideNav, Tabs, PageStack
Dialogs	MessageDialog, QueryDialog, ColorChooser, ColorDropper, DateDialog, FontDialog, FilterDialog, FormDialog
Overlays	Toast, Tooltip
Forms	Form, Field (with validation)

CLI

bootstack ships with an optional CLI for scaffolding, running, and packaging applications:

bootstack gallery                           # Launch the interactive widget gallery
bootstack start MyApp                       # Create a new project (basic template)
bootstack start MyApp --template appshell   # ...or with sidebar navigation
bootstack run                               # Run the app defined in the project config
bootstack add page Dashboard                # Add a new page (appshell)
bootstack add view Settings                 # Add a new view (basic)
bootstack add dialog Preferences            # Add a new dialog
bootstack add theme my-brand                # Scaffold a custom theme
bootstack add i18n --languages en es fr     # Add i18n support
bootstack list themes                       # List available themes
bootstack doctor                            # Diagnose project & environment
bootstack build                             # Package for distribution

Documentation

• Documentation: https://bootstack.org
• Getting Started: https://bootstack.org/getting-started/
• Guides: https://bootstack.org/guides/
• Widgets: https://bootstack.org/widgets/

Links

• GitHub: https://github.com/israel-dryer/bootstack
• Icons: https://github.com/israel-dryer/ttkbootstrap-icons

Acknowledgements

bootstack is derived from ttkbootstrap and continues that project's mission. See NOTICE for license attribution.