diff --git a/.github/ISSUE_TEMPLATE/bug.yml b/.github/ISSUE_TEMPLATE/bug.yml
new file mode 100644
index 0000000..a3625e6
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/bug.yml
@@ -0,0 +1,35 @@
+name: Bug report
+description: Report reproducible incorrect behavior.
+title: "[Bug]: "
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: Please avoid including secrets or private information.
+  - type: input
+    id: version
+    attributes:
+      label: Library version
+      placeholder: 1.0.0
+    validations:
+      required: true
+  - type: input
+    id: board
+    attributes:
+      label: Board and core version
+      placeholder: Arduino Uno, Arduino AVR Boards 1.8.6
+    validations:
+      required: true
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: Minimal sketch and reproduction steps
+      render: cpp
+    validations:
+      required: true
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected and actual behavior
+    validations:
+      required: true
diff --git a/.github/ISSUE_TEMPLATE/config.yml b/.github/ISSUE_TEMPLATE/config.yml
new file mode 100644
index 0000000..4bbbffe
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/config.yml
@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Security report
+    url: https://github.com/devkyato/Custom-Arduino-Libraries/security/advisories/new
+    about: Report vulnerabilities privately.
diff --git a/.github/ISSUE_TEMPLATE/feature.yml b/.github/ISSUE_TEMPLATE/feature.yml
new file mode 100644
index 0000000..06989e6
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/feature.yml
@@ -0,0 +1,30 @@
+name: Feature request
+description: Propose a focused, reusable improvement.
+title: "[Feature]: "
+labels: ["enhancement"]
+body:
+  - type: textarea
+    id: problem
+    attributes:
+      label: Problem
+      description: What project or teaching problem should this solve?
+    validations:
+      required: true
+  - type: textarea
+    id: proposal
+    attributes:
+      label: Proposed API or behavior
+    validations:
+      required: true
+  - type: dropdown
+    id: compatibility
+    attributes:
+      label: Required boards
+      multiple: true
+      options:
+        - AVR / Uno
+        - ESP32
+        - RP2040 / Pico
+        - Other
+    validations:
+      required: true
diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
new file mode 100644
index 0000000..c0415b7
--- /dev/null
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -0,0 +1,14 @@
+## Summary
+
+<!-- What changes for library users? -->
+
+## Verification
+
+- [ ] Native tests pass (`pio test -e native`)
+- [ ] Relevant board environments compile
+- [ ] Documentation or examples are updated
+- [ ] `CHANGELOG.md` is updated for user-visible changes
+
+## Hardware
+
+<!-- List boards and wiring tested, or write "Not hardware-tested". -->
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..478231b
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,9 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+    groups:
+      actions:
+        patterns: ["*"]
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..9ad3bb3
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,48 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  native-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+      - uses: actions/setup-python@v7
+        with:
+          python-version: "3.14"
+      - run: python -m pip install "platformio==6.1.18"
+      - run: pio test -e native
+
+  compile:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        environment: [uno, esp32dev, pico]
+    steps:
+      - uses: actions/checkout@v7
+      - uses: actions/setup-python@v7
+        with:
+          python-version: "3.14"
+      - run: python -m pip install "platformio==6.1.18"
+      - run: pio run -e ${{ matrix.environment }}
+
+  package:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+      - uses: actions/setup-python@v7
+        with:
+          python-version: "3.14"
+      - run: python tools/build_release.py
+      - uses: actions/upload-artifact@v6
+        with:
+          name: ArduinoPatterns
+          path: dist/ArduinoPatterns-*.zip
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
new file mode 100644
index 0000000..2c2a399
--- /dev/null
+++ b/.github/workflows/release.yml
@@ -0,0 +1,27 @@
+name: Release
+
+on:
+  push:
+    tags: ["v*"]
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+      - uses: actions/setup-python@v7
+        with:
+          python-version: "3.14"
+      - name: Verify tag matches library version
+        shell: bash
+        run: |
+          version="$(sed -n 's/^version=//p' library.properties)"
+          test "${GITHUB_REF_NAME}" = "v${version}"
+      - run: python tools/build_release.py
+      - name: Publish GitHub release
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: gh release create "$GITHUB_REF_NAME" dist/*.zip --generate-notes --verify-tag
diff --git a/.gitignore b/.gitignore
index d4fb281..bff5b2c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -39,3 +39,14 @@
 
 # debug information files
 *.dwo
+
+# PlatformIO and editor state
+.pio/
+.vscode/
+
+# Python tooling
+__pycache__/
+*.py[cod]
+
+# Release artifacts
+dist/
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..43fd3ca
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,17 @@
+# Changelog
+
+All notable changes to ArduinoPatterns are documented here. The project follows
+[Semantic Versioning](https://semver.org/).
+
+## [1.0.0] - 2026-07-29
+
+### Added
+
+- `LedBank` for controlling up to 32 active-high or active-low outputs as a mask.
+- `LedAnimator` for rollover-safe, non-blocking timed sequences.
+- `PeriodicOutput` for independent periodic digital outputs.
+- Six Arduino IDE examples adapted from the repository's original exercises.
+- Native timing tests and compile checks for Uno, ESP32, and Raspberry Pi Pico.
+- Arduino IDE ZIP and PlatformIO installation metadata.
+
+[1.0.0]: https://github.com/devkyato/Custom-Arduino-Libraries/releases/tag/v1.0.0
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..9fcdb4d
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,27 @@
+# Code of Conduct
+
+## Our commitment
+
+We are committed to a welcoming, harassment-free learning environment regardless
+of experience level, background, identity, or ability.
+
+## Expected behavior
+
+- Be respectful, patient, and constructive.
+- Explain technical feedback without belittling people.
+- Welcome beginner questions and acknowledge honest mistakes.
+- Keep discussions relevant to the project.
+
+Harassment, personal attacks, discriminatory language, and publishing another
+person's private information are not acceptable.
+
+## Enforcement
+
+Report unacceptable behavior privately to the repository maintainer through the
+contact method on their GitHub profile. Reports will be reviewed fairly and kept
+confidential where possible. Maintainers may edit or remove content, reject
+contributions, or restrict participation when needed.
+
+This policy is adapted from the [Contributor Covenant 2.1][covenant].
+
+[covenant]: https://www.contributor-covenant.org/version/2/1/code_of_conduct/
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..8006a27
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,35 @@
+# Contributing
+
+ArduinoPatterns is intended to be approachable for students and first-time
+open-source contributors.
+
+## Before you start
+
+1. Search existing issues before opening a new one.
+2. For behavior changes or new public APIs, open an issue first.
+3. Keep the library non-blocking and avoid heap allocation.
+
+## Local checks
+
+Install [PlatformIO Core](https://docs.platformio.org/en/latest/core/) and run:
+
+```sh
+pio test -e native
+pio run -e uno
+pio run -e esp32dev
+pio run -e pico
+python tools/build_release.py
+```
+
+Changes to timing logic need a native regression test. New features should include
+an Arduino example or update an existing one. Hardware-dependent changes should
+state the board and wiring used for verification.
+
+## Pull requests
+
+- Keep each pull request focused on one change.
+- Use clear commit messages and explain the user-visible result.
+- Update `CHANGELOG.md` for user-facing changes.
+- Do not commit `.pio`, editor state, or generated `dist` files.
+
+By participating, you agree to follow the [Code of Conduct](CODE_OF_CONDUCT.md).
diff --git a/Exercise_A.ino b/Exercise_A.ino
deleted file mode 100644
index 2b089fe..0000000
--- a/Exercise_A.ino
+++ /dev/null
@@ -1,122 +0,0 @@
-// dito natin dine-declare yung variables ng bawat led
-// bawat variable ay naka assign sa pin number ng arduino
-// ibig sabihin kung saan naka connect yung led sa board
-int led_1 = 6;
-int led_2 = 7;
-int led_3 = 8;
-int led_4 = 9;
-int led_5 = 10;
-int led_6 = 11;
-
-// delay variables para mas madaling baguhin ang timing ng lights
-// milliseconds ang unit ng delay
-// halimbawa 1000 = 1 second
-int led_delay1 = 500;
-int led_delay2 = 1000;
-int led_delay3 = 1500;
-
-void setup() {
-
-  // ang setup() function ay tumatakbo lang isang beses kapag nag start ang arduino
-  // dito natin sine-set ang bawat pin bilang output
-  // kailangan ito para makapag send ang arduino ng signal sa leds
-
-  pinMode(6, OUTPUT);
-  pinMode(7, OUTPUT);
-  pinMode(8, OUTPUT);
-  pinMode(9, OUTPUT);
-  pinMode(10, OUTPUT);
-  pinMode(11, OUTPUT);
-}
-
-void loop() {
-
-  // ang loop() function ay paulit ulit tumatakbo habang naka power ang arduino
-  // dito nangyayari ang iba't ibang led patterns
-
-  // pattern kung saan ang led 1,3,5 ay naka on
-  // habang ang led 2,4,6 ay naka off
-
-  digitalWrite(led_1, HIGH);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, HIGH);
-  digitalWrite(led_4, LOW);
-  digitalWrite(led_5, HIGH);
-  digitalWrite(led_6, LOW);
-
-  // maghihintay muna ng kalahating segundo bago mag change ng pattern
-  delay(500);
-
-  // reverse naman ang pattern
-  // ngayon ang led 2,4,6 ang naka on
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, HIGH);
-  digitalWrite(led_3, LOW);
-  digitalWrite(led_4, HIGH);
-  digitalWrite(led_5, LOW);
-  digitalWrite(led_6, HIGH);
-
-  // hintay ng isang segundo bago next sequence
-  delay(1000);
-
-  // bagong pattern kung saan unang tatlong leds ang naka on
-
-  digitalWrite(led_1, HIGH);
-  digitalWrite(led_2, HIGH);
-  digitalWrite(led_3, HIGH);
-
-  // habang ang huling tatlo ay naka off
-
-  digitalWrite(led_4, LOW);
-  digitalWrite(led_5, LOW);
-  digitalWrite(led_6, LOW);
-
-  delay(1000);
-
-  // reverse ulit ng pattern
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, LOW);
-
-  digitalWrite(led_4, HIGH);
-  digitalWrite(led_5, HIGH);
-  digitalWrite(led_6, HIGH);
-
-  delay(1000);
-
-  // pattern kung saan ang led 1 at led 6 lang ang naka on
-
-  digitalWrite(led_1, HIGH);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, LOW);
-  digitalWrite(led_4, LOW);
-  digitalWrite(led_5, LOW);
-  digitalWrite(led_6, HIGH);
-
-  // mas mahaba ang delay dito kaya 1.5 seconds
-  delay(1500);
-
-  // bagong combination ng leds
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, HIGH);
-  digitalWrite(led_3, LOW);
-  digitalWrite(led_4, LOW);
-  digitalWrite(led_5, HIGH);
-  digitalWrite(led_6, LOW);
-
-  delay(1500);
-
-  // huling combination ng leds sa sequence
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, HIGH);
-  digitalWrite(led_4, HIGH);
-  digitalWrite(led_5, LOW);
-  digitalWrite(led_6, LOW);
-
-  delay(1500);
-}
diff --git a/Exercise_B.ino b/Exercise_B.ino
deleted file mode 100644
index de9123c..0000000
--- a/Exercise_B.ino
+++ /dev/null
@@ -1,55 +0,0 @@
-// mga variable para sa tatlong leds
-// ginagaya nito ang kulay ng traffic light
-// led_1 = green, led_2 = yellow, led_3 = red
-
-int led_1 = 6;
-int led_2 = 7;
-int led_3 = 8;
-
-// delay values para sa bawat phase ng traffic light
-// 5000 ms = 5 seconds
-// 2000 ms = 2 seconds
-
-int led_delay1 = 5000;
-int led_delay2 = 2000;
-int led_delay3 = 5000;
-
-void setup() {
-
-  // dito sine-set ang bawat pin bilang output
-  // para makontrol ng arduino ang pag on at off ng leds
-
-  pinMode(6, OUTPUT);
-  pinMode(7, OUTPUT);
-  pinMode(8, OUTPUT);
-}
-
-void loop() {
-
-  // green light phase
-  // ibig sabihin pwede dumaan ang sasakyan
-
-  digitalWrite(led_1, HIGH);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, LOW);
-
-  delay(5000);
-
-  // yellow light phase
-  // warning ito na malapit na mag red light
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, HIGH);
-  digitalWrite(led_3, LOW);
-
-  delay(2000);
-
-  // red light phase
-  // ibig sabihin stop ang traffic
-
-  digitalWrite(led_1, LOW);
-  digitalWrite(led_2, LOW);
-  digitalWrite(led_3, HIGH);
-
-  delay(5000);
-}
diff --git a/Exercise_C.ino b/Exercise_C.ino
deleted file mode 100644
index 40c88db..0000000
--- a/Exercise_C.ino
+++ /dev/null
@@ -1,71 +0,0 @@
-// apat na leds na gagamitin para sa knight rider effect
-// parang scanning light na gumagalaw mula kaliwa papunta kanan tapos babalik
-
-int led_1 = 6;
-int led_2 = 7;
-int led_3 = 8;
-int led_4 = 9;
-
-void setup() {
-
-  // dito sine-set ang bawat led pin bilang output
-  // kailangan ito para makapag control ang arduino kung on o off ang leds
-
-  pinMode (led_1,OUTPUT);
-  pinMode (led_2,OUTPUT);
-  pinMode (led_3,OUTPUT);
-  pinMode (led_4,OUTPUT);
-}
-
-void loop() {
-
-  // unang led naka on, yung iba naka off
-  // ito ang simula ng movement ng light
-
-  digitalWrite (led_1, HIGH);
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, LOW);
-
-  // delay para makita ang movement
-  delay(1000);
-
-  // lilipat ang ilaw sa led 2
-
-  digitalWrite (led_1, LOW);
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, LOW);
-
-  delay(1000);
-
-  // lilipat naman sa led 3
-
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_1, LOW);
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_4, LOW);
-
-  delay(1000);
-
-  // huling led sa kanan
-
-  digitalWrite (led_4, HIGH);
-  digitalWrite (led_1, LOW);
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, LOW);
-
-  delay(1000);
-
-  // babalik pabalik ang ilaw
-
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, LOW);
-
-  delay(1000);
-
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-
-  delay(1000);
-}
diff --git a/Exercise_D.ino b/Exercise_D.ino
deleted file mode 100644
index 358b58d..0000000
--- a/Exercise_D.ino
+++ /dev/null
@@ -1,59 +0,0 @@
-// gumagamit ito ng array para sa mga led pins
-// mas madali ito kapag maraming leds ang gagamitin
-
-int ledPins[] = {6, 7, 8, 9, 10, 11};
-
-// kinukuha dito kung ilang leds ang nasa array
-// ginagamit ito sa loops para hindi mano-manong ilagay ang bilang
-
-int numLeds = sizeof(ledPins) / sizeof(ledPins[0]);
-
-// delay value sa bawat pagbabago ng led
-int delayTime = 500;
-
-void setup() {
-
-  // ginagamit ang for loop para i-set lahat ng leds bilang output
-  // mas efficient ito kaysa isa-isang pinMode
-
-  for (int i = 0; i < numLeds; i++) {
-    pinMode(ledPins[i], OUTPUT);
-  }
-}
-
-void loop() {
-
-  // tatawagin ang dalawang functions
-  // una ang count up at pagkatapos ang count down
-
-  countUp();
-  countDown();
-}
-
-void countUp() {
-
-  // sa count up phase
-  // isa-isang i-o-on ang leds mula led1 hanggang led6
-
-  for (int i = 0; i < numLeds; i++) {
-
-    digitalWrite(ledPins[i], HIGH);
-
-    // delay para makita ang step by step na pag-on ng leds
-    delay(delayTime);
-  }
-}
-
-void countDown() {
-
-  // sa count down phase
-  // isa-isang i-o-off ang leds mula sa huli pabalik sa una
-
-  for (int i = numLeds - 1; i >= 0; i--) {
-
-    digitalWrite(ledPins[i], LOW);
-
-    // delay ulit para makita ang pagbaba ng count
-    delay(delayTime);
-  }
-}
diff --git a/Exercise_E.ino b/Exercise_E.ino
deleted file mode 100644
index 99deab1..0000000
--- a/Exercise_E.ino
+++ /dev/null
@@ -1,143 +0,0 @@
-// exercise e
-// binary counter gamit ang 4 leds
-// bawat led ay kumakatawan sa isang binary bit
-
-// dito dine-define kung anong pin naka connect ang bawat led
-int led_1 = 6;
-int led_2 = 7;
-int led_3 = 8;
-int led_4 = 9;
- 
-void setup() {
-
-  // sine-set ang bawat pin bilang output
-  // kailangan ito para makapag send ang arduino ng signal sa leds
-
-  pinMode (led_1,OUTPUT);
-  pinMode (led_2,OUTPUT);
-  pinMode (led_3,OUTPUT);
-  pinMode (led_4,OUTPUT);
-}
- 
-void loop() {
-
-  // binary 0001
-  // led4 lang ang naka on
-  digitalWrite (led_1, LOW); //1
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 0010
-  // led3 naman ang naka on
-  digitalWrite (led_1, LOW); //2
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 0011
-  // led3 at led4 naka on
-  digitalWrite (led_1, LOW); //3
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 0100
-  // led2 lang ang naka on
-  digitalWrite (led_1, LOW); //4
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 0101
-  // led2 at led4 naka on
-  digitalWrite (led_1, LOW); //5
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 0110
-  // led2 at led3 naka on
-  digitalWrite (led_1, LOW); //6
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 0111
-  // led2, led3, led4 naka on
-  digitalWrite (led_1, LOW); //7
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 1000
-  // led1 lang ang naka on
-  digitalWrite (led_1, HIGH); //8
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 1001
-  // led1 at led4 naka on
-  digitalWrite (led_1, HIGH); //9
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 1010
-  // led1 at led3 naka on
-  digitalWrite (led_1, HIGH); //10
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 1011
-  // led1, led3, led4 naka on
-  digitalWrite (led_1, HIGH); //11
-  digitalWrite (led_2, LOW);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 1100
-  // led1 at led2 naka on
-  digitalWrite (led_1, HIGH); //12
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 1101
-  // led1, led2, led4 naka on
-  digitalWrite (led_1, HIGH); //13
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, LOW);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-
-  // binary 1110
-  // led1, led2, led3 naka on
-  digitalWrite (led_1, HIGH); //14
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, LOW);
-  delay(1000);
-
-  // binary 1111
-  // lahat ng leds naka on
-  digitalWrite (led_1, HIGH); //15
-  digitalWrite (led_2, HIGH);
-  digitalWrite (led_3, HIGH);
-  digitalWrite (led_4, HIGH);
-  delay(1000);
-}
diff --git a/Exercise_F.ino b/Exercise_F.ino
deleted file mode 100644
index 54a385c..0000000
--- a/Exercise_F.ino
+++ /dev/null
@@ -1,45 +0,0 @@
-// dalawang leds na magbi-blink
-// magkaiba ang timing kaya parang alternating blink effect
-
-int led1 = 9;
-int led2 = 10;
-
-void setup() {
-
-  // sine-set ang pins bilang output para makapag control ng leds
-
-  pinMode(led1, OUTPUT);
-  pinMode(led2, OUTPUT);
-}
-
-void loop() {
-
-  // parehong off ang leds sa simula
-
-  digitalWrite(led1, LOW);
-  digitalWrite(led2, LOW);
-
-  // maghihintay ng kalahating segundo
-  delay(500);
-
-  // led2 lang ang naka on
-
-  digitalWrite(led1, LOW);
-  digitalWrite(led2, HIGH);
-
-  delay(500);
-
-  // led1 naman ang naka on habang led2 naka off
-
-  digitalWrite(led1, HIGH);
-  digitalWrite(led2, LOW);
-
-  delay(500);
-
-  // parehong leds naka on
-
-  digitalWrite(led1, HIGH);
-  digitalWrite(led2, HIGH);
-
-  delay(500);
-}
diff --git a/README.md b/README.md
index 971524e..34c919d 100644
--- a/README.md
+++ b/README.md
@@ -1,80 +1,78 @@
-# Supplementary Exercise 1 – Arduino LED Exercises
+# ArduinoPatterns
 
-This repository contains our solutions for **Supplementary Exercise No. 1 – Introduction to Microcontroller (Arduino) & Digital Output**.  
-The exercises focus on controlling LEDs using an Arduino and practicing basic programming logic such as sequences, delays, counting, and patterns.
+[![CI](https://github.com/devkyato/Custom-Arduino-Libraries/actions/workflows/ci.yml/badge.svg)](https://github.com/devkyato/Custom-Arduino-Libraries/actions/workflows/ci.yml)
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
 
-Each `.ino` file corresponds to a specific exercise given in the activity instructions. The programs demonstrate different LED behaviors like alternating lights, traffic light simulation, chasing LEDs, counting patterns, binary counting, and blinking with different timings.
+ArduinoPatterns is a small teaching library for coordinating LEDs and other digital
+outputs without `delay()`. It turns the original laboratory sketches in this
+repository into reusable components that can run alongside buttons, sensors,
+displays, networking, and serial communication.
 
-## Exercises Included
+## Features
 
-### Exercise A – Alternating Lights
-Simulates alternating LED patterns using six LEDs.  
-Different combinations of LEDs turn on with different delay timings.
+- `LedBank`: treat up to 32 output pins as a bit mask.
+- `LedAnimator`: play timed mask sequences using rollover-safe `millis()` logic.
+- `PeriodicOutput`: blink independent outputs at different rates.
+- No heap allocation, third-party dependencies, interrupts, or board-specific API.
+- Arduino IDE and PlatformIO examples for traffic lights, scanning, counting,
+  alternating patterns, and independent blinkers.
 
-**Done by:** Maurene
+## Install
 
----
+Download the latest release ZIP and choose **Sketch > Include Library > Add .ZIP
+Library** in Arduino IDE. In PlatformIO:
 
-### Exercise B – Traffic Light Simulation
-A simple traffic light system using three LEDs:
-- Green → Yellow → Red  
-Each light stays on for a specific duration to mimic real traffic lights.
+```ini
+lib_deps =
+  https://github.com/devkyato/Custom-Arduino-Libraries.git#v1.0.0
+```
 
-**Done by:** Maurene
+## Quick example
 
----
+```cpp
+#include <ArduinoPatterns.h>
 
-### Exercise C – Knight Rider (Chasing LEDs)
-Creates a "Knight Rider" style LED effect where lights turn on one by one from left to right, then reverse back.
+const uint8_t pins[] = {6, 7, 8};
+const PatternStep traffic[] = {
+    {0b001, 5000},  // green
+    {0b010, 2000},  // yellow
+    {0b100, 5000},  // red
+};
 
-**Done by:** Mayellah
+LedBank lights(pins, 3);
+LedAnimator animation(lights, traffic, 3);
 
----
+void setup() {
+  lights.begin();
+  animation.start(millis());
+}
 
-### Exercise D – Count Up and Down LEDs
-Uses six LEDs to simulate counting:
-- First counts **up** by turning LEDs on one by one
-- Then counts **down** by turning them off one by one
+void loop() {
+  animation.update(millis());
+  // Other application work can run here.
+}
+```
 
-**Done by:** Marquez
+Open **File > Examples > ArduinoPatterns** for complete sketches. The examples map
+the original student work into reusable patterns; the original commits remain in
+the repository history.
 
----
+See the [API reference](docs/API.md) for lifecycle, ownership, rollover, and
+active-low behavior.
 
-### Exercise E – LED Binary Counter
-Uses four LEDs to represent binary numbers from **0 to 15**.  
-Each LED represents a binary bit that turns ON or OFF depending on the number.
+## Compatibility
 
-**Done by:** Mayellah
+The public API uses only `pinMode`, `digitalWrite`, and unsigned millisecond
+arithmetic. CI compiles for Arduino AVR Uno, ESP32, and RP2040. Other Arduino
+architectures are expected to work but should be reported as verified only after an
+actual compile or hardware test.
 
----
+## Contributing
 
-### Exercise F – Double Blink with Different Timings
-Two LEDs blink at different speeds:
-- LED1 blinks every **1 second**
-- LED2 blinks every **0.5 seconds**
+Student-friendly issues are labeled `good first issue`. Changes should remain
+non-blocking, avoid dynamic allocation, include native tests for timing logic, and
+compile at least the Uno example. See [CONTRIBUTING.md](CONTRIBUTING.md).
 
-**Done by:** Marquez
+## License
 
----
-
-## Materials Used
-- Arduino Microcontroller  
-- Data Cable  
-- Computer  
-- Connecting Wires  
-- LEDs  
-
----
-
-## Group Members
-
-**Group 4**
-
-- Maurene – Exercise A & B  
-- Mayellah – Exercise C & E  
-- Marquez – Exercise D & F  
-
----
-
-## Notes
-These exercises were created as part of a laboratory activity for learning the basics of **Arduino programming and digital output control**.
+[MIT](LICENSE)
diff --git a/SECURITY.md b/SECURITY.md
new file mode 100644
index 0000000..3f7e9f5
--- /dev/null
+++ b/SECURITY.md
@@ -0,0 +1,16 @@
+# Security policy
+
+## Supported versions
+
+Security fixes are provided for the latest release.
+
+## Reporting a vulnerability
+
+Please do not open a public issue for a suspected vulnerability. Use GitHub's
+private vulnerability reporting feature on the repository's **Security** tab.
+Include the affected version, board, a minimal reproduction, and the potential
+impact. You should receive an initial response within seven days.
+
+This library directly controls GPIO and does not process network input, but
+memory-safety, unexpected pin-state, and denial-of-service findings are still
+welcome.
diff --git a/docs/API.md b/docs/API.md
new file mode 100644
index 0000000..293eee9
--- /dev/null
+++ b/docs/API.md
@@ -0,0 +1,70 @@
+# API reference
+
+Include the library with:
+
+```cpp
+#include <ArduinoPatterns.h>
+```
+
+## `PatternStep`
+
+```cpp
+struct PatternStep {
+  uint32_t mask;
+  uint32_t durationMs;
+};
+```
+
+Bit zero in `mask` controls the first pin in a `LedBank`. `durationMs` is the
+time before advancing to the next step. A zero-duration step advances at most
+once per `update()` call, preventing an infinite loop.
+
+## `LedBank`
+
+```cpp
+LedBank(const uint8_t* pins, size_t count, bool activeHigh = true);
+```
+
+The caller owns the pin array and must keep it alive for as long as the bank is
+used. A bank supports 1–32 pins. A larger count or null pin array creates an
+invalid bank.
+
+- `begin()` configures pins as outputs and clears them.
+- `writeMask(mask)` writes the lowest `count` bits.
+- `clear()` turns every logical output off.
+- `size()`, `mask()`, and `valid()` inspect current state.
+
+With `activeHigh = false`, a logical on state writes `LOW`, which is useful for
+active-low relay and LED modules.
+
+## `LedAnimator`
+
+```cpp
+LedAnimator(LedBank& bank, const PatternStep* steps, size_t count,
+            bool repeat = true);
+```
+
+- `start(now)` selects step zero and returns whether the configuration is valid.
+- `update(now)` catches up all elapsed non-zero-duration steps without blocking.
+- `stop(clearOutputs)` stops playback and optionally clears the bank.
+- `setRepeat(repeat)` changes end-of-sequence behavior.
+- `running()` and `currentStep()` expose playback state.
+
+Pass the current `millis()` value to `start()` and `update()`. Unsigned
+subtraction makes elapsed-time checks safe across the `millis()` rollover.
+
+## `PeriodicOutput`
+
+```cpp
+PeriodicOutput(uint8_t pin, uint32_t intervalMs,
+               bool activeHigh = true, bool initialState = false);
+```
+
+- `begin(now)` configures and writes the initial state.
+- `update(now)` processes elapsed intervals and reports whether any interval
+  elapsed. When an even number was skipped, the final logical state is unchanged.
+- `setInterval(intervalMs, now)` updates the period and restarts its timer.
+- `set(active, now)` writes a logical state and restarts its timer.
+- `active()` and `interval()` return the current configuration.
+
+An interval of zero disables automatic toggling.
diff --git a/examples/AlternatingPatterns/AlternatingPatterns.ino b/examples/AlternatingPatterns/AlternatingPatterns.ino
new file mode 100644
index 0000000..73152bf
--- /dev/null
+++ b/examples/AlternatingPatterns/AlternatingPatterns.ino
@@ -0,0 +1,22 @@
+#include <ArduinoPatterns.h>
+
+const uint8_t pins[] = {6, 7, 8, 9, 10, 11};
+const PatternStep steps[] = {
+    {0b010101, 500},
+    {0b101010, 1000},
+    {0b000111, 1000},
+    {0b111000, 1000},
+    {0b100001, 1500},
+    {0b010010, 1500},
+    {0b001100, 1500},
+};
+
+LedBank lights(pins, sizeof(pins));
+LedAnimator animation(lights, steps, sizeof(steps) / sizeof(steps[0]));
+
+void setup() {
+  lights.begin();
+  animation.start(millis());
+}
+
+void loop() { animation.update(millis()); }
diff --git a/examples/BinaryCounter/BinaryCounter.ino b/examples/BinaryCounter/BinaryCounter.ino
new file mode 100644
index 0000000..fe87b89
--- /dev/null
+++ b/examples/BinaryCounter/BinaryCounter.ino
@@ -0,0 +1,21 @@
+#include <ArduinoPatterns.h>
+
+const uint8_t pins[] = {9, 8, 7, 6};  // least-significant bit first
+LedBank bits(pins, sizeof(pins));
+
+uint8_t value = 0;
+uint32_t changedAt = 0;
+
+void setup() {
+  bits.begin();
+  bits.writeMask(value);
+}
+
+void loop() {
+  const uint32_t now = millis();
+  if (static_cast<uint32_t>(now - changedAt) >= 1000) {
+    changedAt += 1000;
+    value = (value + 1) & 0x0F;
+    bits.writeMask(value);
+  }
+}
diff --git a/examples/CountUpDown/CountUpDown.ino b/examples/CountUpDown/CountUpDown.ino
new file mode 100644
index 0000000..a988b89
--- /dev/null
+++ b/examples/CountUpDown/CountUpDown.ino
@@ -0,0 +1,28 @@
+#include <ArduinoPatterns.h>
+
+const uint8_t pins[] = {6, 7, 8, 9, 10, 11};
+const PatternStep countSteps[] = {
+    {0b000001, 300},
+    {0b000011, 300},
+    {0b000111, 300},
+    {0b001111, 300},
+    {0b011111, 300},
+    {0b111111, 300},
+    {0b011111, 300},
+    {0b001111, 300},
+    {0b000111, 300},
+    {0b000011, 300},
+    {0b000001, 300},
+    {0b000000, 300},
+};
+
+LedBank lights(pins, sizeof(pins));
+LedAnimator counter(lights, countSteps,
+                    sizeof(countSteps) / sizeof(countSteps[0]));
+
+void setup() {
+  lights.begin();
+  counter.start(millis());
+}
+
+void loop() { counter.update(millis()); }
diff --git a/examples/IndependentBlink/IndependentBlink.ino b/examples/IndependentBlink/IndependentBlink.ino
new file mode 100644
index 0000000..6696ad6
--- /dev/null
+++ b/examples/IndependentBlink/IndependentBlink.ino
@@ -0,0 +1,16 @@
+#include <ArduinoPatterns.h>
+
+PeriodicOutput slowLed(9, 1000);
+PeriodicOutput fastLed(10, 500);
+
+void setup() {
+  const uint32_t now = millis();
+  slowLed.begin(now);
+  fastLed.begin(now);
+}
+
+void loop() {
+  const uint32_t now = millis();
+  slowLed.update(now);
+  fastLed.update(now);
+}
diff --git a/examples/ScanningLight/ScanningLight.ino b/examples/ScanningLight/ScanningLight.ino
new file mode 100644
index 0000000..317cd35
--- /dev/null
+++ b/examples/ScanningLight/ScanningLight.ino
@@ -0,0 +1,21 @@
+#include <ArduinoPatterns.h>
+
+const uint8_t pins[] = {6, 7, 8, 9};
+const PatternStep scan[] = {
+    {0b0001, 180},
+    {0b0010, 180},
+    {0b0100, 180},
+    {0b1000, 180},
+    {0b0100, 180},
+    {0b0010, 180},
+};
+
+LedBank lights(pins, sizeof(pins));
+LedAnimator scanner(lights, scan, sizeof(scan) / sizeof(scan[0]));
+
+void setup() {
+  lights.begin();
+  scanner.start(millis());
+}
+
+void loop() { scanner.update(millis()); }
diff --git a/examples/TrafficLight/TrafficLight.ino b/examples/TrafficLight/TrafficLight.ino
new file mode 100644
index 0000000..f995b98
--- /dev/null
+++ b/examples/TrafficLight/TrafficLight.ino
@@ -0,0 +1,20 @@
+#include <ArduinoPatterns.h>
+
+// Pins are ordered green, yellow, red; bit 0 maps to the first pin.
+const uint8_t pins[] = {6, 7, 8};
+const PatternStep phases[] = {
+    {0b001, 5000},
+    {0b010, 2000},
+    {0b100, 5000},
+};
+
+LedBank trafficLights(pins, sizeof(pins));
+LedAnimator traffic(trafficLights, phases,
+                    sizeof(phases) / sizeof(phases[0]));
+
+void setup() {
+  trafficLights.begin();
+  traffic.start(millis());
+}
+
+void loop() { traffic.update(millis()); }
diff --git a/keywords.txt b/keywords.txt
new file mode 100644
index 0000000..ee2952a
--- /dev/null
+++ b/keywords.txt
@@ -0,0 +1,10 @@
+LedBank	KEYWORD1
+LedAnimator	KEYWORD1
+PeriodicOutput	KEYWORD1
+PatternStep	KEYWORD1
+begin	KEYWORD2
+writeMask	KEYWORD2
+start	KEYWORD2
+stop	KEYWORD2
+update	KEYWORD2
+setInterval	KEYWORD2
diff --git a/library.json b/library.json
new file mode 100644
index 0000000..9c2acdb
--- /dev/null
+++ b/library.json
@@ -0,0 +1,15 @@
+{
+  "name": "ArduinoPatterns",
+  "version": "1.0.0",
+  "description": "Non-blocking LED and digital-output patterns for Arduino.",
+  "keywords": ["arduino", "led", "non-blocking", "millis", "education"],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/devkyato/Custom-Arduino-Libraries.git"
+  },
+  "authors": [{"name": "devkyato", "maintainer": true}],
+  "license": "MIT",
+  "frameworks": ["arduino"],
+  "platforms": "*",
+  "headers": "ArduinoPatterns.h"
+}
diff --git a/library.properties b/library.properties
new file mode 100644
index 0000000..7e4e7bb
--- /dev/null
+++ b/library.properties
@@ -0,0 +1,10 @@
+name=ArduinoPatterns
+version=1.0.0
+author=devkyato and contributors
+maintainer=devkyato
+sentence=Non-blocking LED and digital-output patterns for Arduino.
+paragraph=Coordinate timed LED sequences, bit-mask output banks, and independent periodic outputs without delay() or heap allocation.
+category=Signal Input/Output
+url=https://github.com/devkyato/Custom-Arduino-Libraries
+architectures=*
+includes=ArduinoPatterns.h
diff --git a/platformio.ini b/platformio.ini
new file mode 100644
index 0000000..5bd45d4
--- /dev/null
+++ b/platformio.ini
@@ -0,0 +1,29 @@
+[platformio]
+default_envs = uno, esp32dev, pico
+src_dir = examples/TrafficLight
+
+[env]
+framework = arduino
+lib_extra_dirs = .
+build_flags = -Wall -Wextra
+
+[env:uno]
+platform = atmelavr
+board = uno
+
+[env:esp32dev]
+platform = espressif32
+board = esp32dev
+
+[env:pico]
+platform = raspberrypi
+board = pico
+
+[env:native]
+platform = native
+framework =
+test_framework = custom
+build_flags =
+  -std=c++17
+  -I test/test_native
+lib_ignore = Unity
diff --git a/src/ArduinoPatterns.cpp b/src/ArduinoPatterns.cpp
new file mode 100644
index 0000000..ef900f2
--- /dev/null
+++ b/src/ArduinoPatterns.cpp
@@ -0,0 +1,156 @@
+#include "ArduinoPatterns.h"
+
+LedBank::LedBank(const uint8_t* pins, size_t count, bool activeHigh)
+    : pins_(pins),
+      count_(count <= kMaximumPins ? count : 0),
+      activeHigh_(activeHigh),
+      mask_(0) {}
+
+void LedBank::begin() {
+  if (!valid()) {
+    return;
+  }
+  for (size_t index = 0; index < count_; ++index) {
+    pinMode(pins_[index], OUTPUT);
+  }
+  clear();
+}
+
+void LedBank::writeMask(uint32_t mask) {
+  if (!valid()) {
+    return;
+  }
+  const uint32_t bounded =
+      count_ == kMaximumPins ? mask : mask & ((uint32_t{1} << count_) - 1);
+  for (size_t index = 0; index < count_; ++index) {
+    const bool active = (bounded & (uint32_t{1} << index)) != 0;
+    digitalWrite(pins_[index], active == activeHigh_ ? HIGH : LOW);
+  }
+  mask_ = bounded;
+}
+
+void LedBank::clear() { writeMask(0); }
+
+size_t LedBank::size() const { return count_; }
+
+uint32_t LedBank::mask() const { return mask_; }
+
+bool LedBank::valid() const { return pins_ != nullptr && count_ > 0; }
+
+LedAnimator::LedAnimator(LedBank& bank, const PatternStep* steps, size_t count,
+                         bool repeat)
+    : bank_(bank),
+      steps_(steps),
+      count_(count),
+      repeat_(repeat),
+      running_(false),
+      current_(0),
+      changedAt_(0) {}
+
+bool LedAnimator::start(uint32_t now) {
+  if (!bank_.valid() || steps_ == nullptr || count_ == 0) {
+    running_ = false;
+    return false;
+  }
+  current_ = 0;
+  changedAt_ = now;
+  running_ = true;
+  bank_.writeMask(steps_[current_].mask);
+  return true;
+}
+
+void LedAnimator::stop(bool clearOutputs) {
+  running_ = false;
+  if (clearOutputs) {
+    bank_.clear();
+  }
+}
+
+bool LedAnimator::update(uint32_t now) {
+  if (!running_) {
+    return false;
+  }
+
+  bool changed = false;
+  while (running_ && static_cast<uint32_t>(now - changedAt_) >=
+                         steps_[current_].durationMs) {
+    const uint32_t duration = steps_[current_].durationMs;
+    changedAt_ += duration;
+    advance(now);
+    changed = true;
+    if (duration == 0) {
+      changedAt_ = now;
+      break;
+    }
+  }
+  return changed;
+}
+
+void LedAnimator::setRepeat(bool repeat) { repeat_ = repeat; }
+
+bool LedAnimator::running() const { return running_; }
+
+size_t LedAnimator::currentStep() const { return current_; }
+
+void LedAnimator::advance(uint32_t now) {
+  if (current_ + 1 < count_) {
+    ++current_;
+    bank_.writeMask(steps_[current_].mask);
+    return;
+  }
+  if (repeat_) {
+    current_ = 0;
+    bank_.writeMask(steps_[current_].mask);
+    return;
+  }
+  running_ = false;
+  changedAt_ = now;
+}
+
+PeriodicOutput::PeriodicOutput(uint8_t pin, uint32_t intervalMs,
+                               bool activeHigh, bool initialState)
+    : pin_(pin),
+      intervalMs_(intervalMs),
+      activeHigh_(activeHigh),
+      state_(initialState),
+      changedAt_(0) {}
+
+void PeriodicOutput::begin(uint32_t now) {
+  pinMode(pin_, OUTPUT);
+  changedAt_ = now;
+  write();
+}
+
+bool PeriodicOutput::update(uint32_t now) {
+  if (intervalMs_ == 0 ||
+      static_cast<uint32_t>(now - changedAt_) < intervalMs_) {
+    return false;
+  }
+  const uint32_t elapsed = static_cast<uint32_t>(now - changedAt_);
+  const uint32_t periods = elapsed / intervalMs_;
+  changedAt_ += periods * intervalMs_;
+  if ((periods & 1U) != 0) {
+    state_ = !state_;
+    write();
+  }
+  return true;
+}
+
+void PeriodicOutput::setInterval(uint32_t intervalMs, uint32_t now) {
+  intervalMs_ = intervalMs;
+  changedAt_ = now;
+}
+
+void PeriodicOutput::set(bool active, uint32_t now) {
+  state_ = active;
+  changedAt_ = now;
+  write();
+}
+
+bool PeriodicOutput::active() const { return state_; }
+
+uint32_t PeriodicOutput::interval() const { return intervalMs_; }
+
+void PeriodicOutput::write() {
+  digitalWrite(pin_, state_ == activeHigh_ ? HIGH : LOW);
+}
diff --git a/src/ArduinoPatterns.h b/src/ArduinoPatterns.h
new file mode 100644
index 0000000..b85010c
--- /dev/null
+++ b/src/ArduinoPatterns.h
@@ -0,0 +1,80 @@
+#pragma once
+
+#include <Arduino.h>
+
+#include <stddef.h>
+#include <stdint.h>
+
+struct PatternStep {
+  uint32_t mask;
+  uint32_t durationMs;
+};
+
+class LedBank {
+ public:
+  static constexpr size_t kMaximumPins = 32;
+
+  LedBank(const uint8_t* pins, size_t count, bool activeHigh = true);
+
+  void begin();
+  void writeMask(uint32_t mask);
+  void clear();
+
+  size_t size() const;
+  uint32_t mask() const;
+  bool valid() const;
+
+ private:
+  const uint8_t* pins_;
+  size_t count_;
+  bool activeHigh_;
+  uint32_t mask_;
+};
+
+class LedAnimator {
+ public:
+  LedAnimator(LedBank& bank, const PatternStep* steps, size_t count,
+              bool repeat = true);
+
+  bool start(uint32_t now);
+  void stop(bool clearOutputs = true);
+  bool update(uint32_t now);
+  void setRepeat(bool repeat);
+
+  bool running() const;
+  size_t currentStep() const;
+
+ private:
+  LedBank& bank_;
+  const PatternStep* steps_;
+  size_t count_;
+  bool repeat_;
+  bool running_;
+  size_t current_;
+  uint32_t changedAt_;
+
+  void advance(uint32_t now);
+};
+
+class PeriodicOutput {
+ public:
+  PeriodicOutput(uint8_t pin, uint32_t intervalMs, bool activeHigh = true,
+                 bool initialState = false);
+
+  void begin(uint32_t now);
+  bool update(uint32_t now);
+  void setInterval(uint32_t intervalMs, uint32_t now);
+  void set(bool active, uint32_t now);
+
+  bool active() const;
+  uint32_t interval() const;
+
+ private:
+  uint8_t pin_;
+  uint32_t intervalMs_;
+  bool activeHigh_;
+  bool state_;
+  uint32_t changedAt_;
+
+  void write();
+};
diff --git a/test/test_custom_runner.py b/test/test_custom_runner.py
new file mode 100644
index 0000000..094385b
--- /dev/null
+++ b/test/test_custom_runner.py
@@ -0,0 +1,11 @@
+from platformio.public import TestCase, TestRunnerBase, TestStatus
+
+
+class CustomTestRunner(TestRunnerBase):
+    """Use PlatformIO's native build/run stages and the program exit code."""
+
+    def stage_testing(self):
+        super().stage_testing()
+        self.test_suite.add_case(
+            TestCase(name="native_assertions", status=TestStatus.PASSED)
+        )
diff --git a/test/test_native/Arduino.h b/test/test_native/Arduino.h
new file mode 100644
index 0000000..afb5bee
--- /dev/null
+++ b/test/test_native/Arduino.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+
+#define LOW 0x0
+#define HIGH 0x1
+#define OUTPUT 0x1
+
+void pinMode(uint8_t pin, uint8_t mode);
+void digitalWrite(uint8_t pin, uint8_t value);
+uint32_t millis();
diff --git a/test/test_native/test_main.cpp b/test/test_native/test_main.cpp
new file mode 100644
index 0000000..b272eff
--- /dev/null
+++ b/test/test_native/test_main.cpp
@@ -0,0 +1,120 @@
+#include <ArduinoPatterns.h>
+
+#include <cassert>
+#include <climits>
+#include <cstring>
+
+namespace {
+uint8_t modes[256];
+uint8_t values[256];
+uint32_t fakeMillis;
+}  // namespace
+
+void pinMode(uint8_t pin, uint8_t mode) { modes[pin] = mode; }
+
+void digitalWrite(uint8_t pin, uint8_t value) { values[pin] = value; }
+
+uint32_t millis() { return fakeMillis; }
+
+void resetFakes() {
+  std::memset(modes, 0, sizeof(modes));
+  std::memset(values, 0, sizeof(values));
+  fakeMillis = 0;
+}
+
+void test_led_bank_initializes_and_writes_masks() {
+  resetFakes();
+  const uint8_t pins[] = {2, 4, 7};
+  LedBank bank(pins, 3);
+  assert(bank.valid());
+
+  bank.begin();
+  assert(modes[2] == OUTPUT);
+  assert(values[2] == LOW);
+
+  bank.writeMask(0b101);
+  assert(values[2] == HIGH);
+  assert(values[4] == LOW);
+  assert(values[7] == HIGH);
+  assert(bank.mask() == 0b101);
+
+  bank.writeMask(0xFFFFFFFF);
+  assert(bank.mask() == 0b111);
+}
+
+void test_led_bank_supports_active_low_outputs() {
+  resetFakes();
+  const uint8_t pins[] = {3};
+  LedBank bank(pins, 1, false);
+  bank.begin();
+  assert(values[3] == HIGH);
+  bank.writeMask(1);
+  assert(values[3] == LOW);
+}
+
+void test_animator_advances_without_delay_and_catches_up() {
+  resetFakes();
+  const uint8_t pins[] = {2, 3};
+  const PatternStep steps[] = {{0b01, 10}, {0b10, 20}, {0b11, 30}};
+  LedBank bank(pins, 2);
+  LedAnimator animation(bank, steps, 3);
+  bank.begin();
+
+  assert(animation.start(100));
+  assert(bank.mask() == 0b01);
+  assert(!animation.update(109));
+  assert(animation.update(130));
+  assert(bank.mask() == 0b11);
+  assert(animation.currentStep() == 2);
+}
+
+void test_animator_handles_millis_rollover() {
+  resetFakes();
+  const uint8_t pins[] = {2};
+  const PatternStep steps[] = {{0, 10}, {1, 10}};
+  LedBank bank(pins, 1);
+  LedAnimator animation(bank, steps, 2, false);
+  bank.begin();
+
+  animation.start(UINT32_MAX - 5);
+  assert(animation.update(4));
+  assert(bank.mask() == 1);
+}
+
+void test_non_repeating_animation_stops() {
+  resetFakes();
+  const uint8_t pins[] = {2};
+  const PatternStep steps[] = {{1, 5}, {0, 5}};
+  LedBank bank(pins, 1);
+  LedAnimator animation(bank, steps, 2, false);
+  bank.begin();
+  animation.start(0);
+
+  animation.update(10);
+  assert(!animation.running());
+  assert(bank.mask() == 0);
+}
+
+void test_periodic_output_handles_skipped_periods() {
+  resetFakes();
+  PeriodicOutput output(9, 100, true, false);
+  output.begin(0);
+  assert(values[9] == LOW);
+
+  assert(output.update(100));
+  assert(output.active());
+  assert(output.update(300));
+  assert(output.active());
+  assert(output.update(400));
+  assert(!output.active());
+}
+
+int main(int, char**) {
+  test_led_bank_initializes_and_writes_masks();
+  test_led_bank_supports_active_low_outputs();
+  test_animator_advances_without_delay_and_catches_up();
+  test_animator_handles_millis_rollover();
+  test_non_repeating_animation_stops();
+  test_periodic_output_handles_skipped_periods();
+  return 0;
+}
diff --git a/tools/build_release.py b/tools/build_release.py
new file mode 100644
index 0000000..6d201ab
--- /dev/null
+++ b/tools/build_release.py
@@ -0,0 +1,68 @@
+"""Build a deterministic Arduino IDE library ZIP."""
+
+from __future__ import annotations
+
+import configparser
+import zipfile
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+DIST = ROOT / "dist"
+INCLUDED = (
+    "src",
+    "examples",
+    "README.md",
+    "CHANGELOG.md",
+    "LICENSE",
+    "library.properties",
+    "library.json",
+    "keywords.txt",
+)
+FIXED_TIME = (2026, 1, 1, 0, 0, 0)
+
+
+def library_version() -> str:
+    parser = configparser.ConfigParser()
+    text = "[library]\n" + (ROOT / "library.properties").read_text(encoding="utf-8")
+    parser.read_string(text)
+    return parser["library"]["version"]
+
+
+def files_to_package() -> list[Path]:
+    files: list[Path] = []
+    for item in INCLUDED:
+        path = ROOT / item
+        if path.is_dir():
+            files.extend(candidate for candidate in path.rglob("*") if candidate.is_file())
+        else:
+            files.append(path)
+    return sorted(files, key=lambda path: path.as_posix())
+
+
+def main() -> None:
+    version = library_version()
+    DIST.mkdir(exist_ok=True)
+    output = DIST / f"ArduinoPatterns-{version}.zip"
+
+    with zipfile.ZipFile(output, "w", compression=zipfile.ZIP_DEFLATED) as archive:
+        for path in files_to_package():
+            relative = path.relative_to(ROOT).as_posix()
+            info = zipfile.ZipInfo(f"ArduinoPatterns/{relative}", FIXED_TIME)
+            info.compress_type = zipfile.ZIP_DEFLATED
+            info.external_attr = 0o100644 << 16
+            archive.writestr(info, path.read_bytes())
+
+    with zipfile.ZipFile(output) as archive:
+        required = {
+            "ArduinoPatterns/library.properties",
+            "ArduinoPatterns/src/ArduinoPatterns.h",
+        }
+        missing = required.difference(archive.namelist())
+        if missing:
+            raise RuntimeError(f"release archive is missing: {sorted(missing)}")
+
+    print(output)
+
+
+if __name__ == "__main__":
+    main()