🐍 Anpyra · Python to Native Android

Write small Android apps in a typed Python subset, compile them directly to DEX, and build signed APKs. Anpyra is a Python-written compiler and build framework based on the PyAndroid experiments 001–008.

Status: v0.1.3 alpha. Android is the only implemented target. This release adds native Button shapes, state colors, ripple, placement/margins and raster icons alongside Screen styling and expanded TextView typography with system/local fonts, size, alignment, padding, spacing, overflow, decorations, shadows and selection. Screen rendering passed 25 pixel checks and typography passed 30 recorded cases and Button passed 20 native cases on Android API 33. Other Android versions, broader lifecycle behavior and independent binary verification still need recorded coverage.

🐍 Python-based builds

Build with Python 3.11+ and Python dependencies. No Java/JDK, Kotlin, Android SDK build kit, Android NDK, Android Studio, Gradle, D8, R8, AAPT2 or apksigner is required. cryptography and Pillow are installed automatically for signing and Screen image/color handling. Optional adb provides device installation.

⚡ Install the published package

Install from PyPI using uv (recommended):

uv venv --python 3.12
uv pip install "anpyra==0.1.3"

Or use pip inside a virtual environment:

python -m pip install "anpyra==0.1.3"

Activate your environment, then:

anpyra doctor
anpyra init myapp --package dev.example.myapp --label "My App"
anpyra check myapp
anpyra build myapp
anpyra verify myapp/build/dev.example.myapp.apk

For checkout installation and host-specific commands, see the installation guide.

🔄 Upgrade from an earlier release

Use the same environment where you installed Anpyra. With that environment activated, choose uv (recommended) or pip:

uv pip install --upgrade "anpyra==0.1.3"
# Or:
python -m pip install --upgrade "anpyra==0.1.3"
python -m anpyra --version

The version should print Anpyra 0.1.3. To upgrade to the latest compatible release, use --upgrade anpyra without the version pin. Keep your app's .anpyra/ signing identity and rebuild its APK after upgrading. See the upgrade guide for explicit environment paths.

🧩 Application example

from anpyra import Activity
from anpyra.components import Font, TextView


class MainActivity(Activity):
    def on_create(self, state):
        title = TextView(self, text="Hello from Anpyra!")
        title.style.color = "#663399"
        title.style.size = 28
        title.style.font = Font(family="sans-serif", bold=True)
        title.style.padding = (16, 24)
        title.style.width = "match_parent"
        title.style.alignment = "center"
        self.set_content_view(title)

Anpyra parses application source on the host. Android runs the generated bytecode. The authoring classes provide editor support; they do not preview a UI on the host.

🟦 Native Button example

from anpyra import Activity
from anpyra.components import Button, Border


class MainActivity(Activity):
    def on_create(self, state):
        button = Button(self, text="Continue")
        button.style.bg.color = "#2563eb"
        button.style.color = "white"
        button.style.all_caps = False
        button.style.corner_radius = 16
        button.style.border = Border("#93c5fd", width=2)
        button.style.width = 260
        button.style.height = 64
        button.style.placement = "center"
        button.style.pressed.bg.color = "#1e40af"
        button.style.ripple_color = "#50ffffff"
        self.set_content_view(button)

This example demonstrates native design and press feedback. Python click-action callbacks are not compiled in this version.

📦 Supported features and limits

• One Activity and TextView with Font/Shadow/TextStyle declarations, constructor text, typography, dp dimensions/padding, sp size and native selection.
• Native Button design with shared typography, state colors, rounded shapes, stroke, ripple, layout/margins and signed raster icons.
• Validated standalone local TTF/OTF fonts preserved in signed digest-named APK assets.
• Screen colors, local raster images with seven fit modes, linear/radial/sweep gradients and transparency.
• Initialized str, int and bool locals, simple integer arithmetic and comparisons.
• Nested conditions and typed integer helper functions.
• DEX, binary manifest, signed APK and JSON report generation.
• Retained project debug identity and local APK/DEX integrity checks.

This is a restricted compiler, not general Python on Android. A Screen supports one TextView or Button content child and static styling. General layouts/multiple children, callbacks, arbitrary imports, collections, reassignment, multi-module apps and release/store signing are not implemented. Source locals/temporaries have a 14-symbol budget; rendering uses separate scratch registers. See the Screen guide, TextView guide, Button guide and language guide.

📚 Documentation and contribution

User guide · Developer guide · Roadmap · Issues · Contributing

Anpyra is licensed under Apache-2.0.