Add citation and accessibility publication polish

ACCESSIBILITY.md

@@ -0,0 +1,67 @@
+# Accessibility Guide
+
+This repository is primarily text- and code-based. The goal of this guide is to keep the course usable for learners who rely on keyboard navigation, screen readers, zoom, high-contrast settings, or reduced visual complexity.
+
+## Learner guidance
+
+The course can be used directly in GitHub or through Google Colab.
+
+For a lower-friction path:
+
+1. begin with [Start Here](START_HERE.md);
+2. use the [Colab notebook index](COLAB.md);
+3. increase browser/Colab zoom or font size as needed;
+4. use the Markdown course notes when notebook rendering is difficult;
+5. use the module README, exercises, assignment, and mastery checks as text alternatives to notebook navigation.
+
+## Content authoring rules
+
+When adding or editing course material:
+
+- use descriptive headings in logical order;
+- use meaningful link text instead of "click here";
+- keep code examples small and explain their purpose in surrounding text;
+- do not rely on color alone to communicate meaning;
+- provide text explanations for diagrams and visual relationships;
+- add useful alt text to images if images are introduced;
+- keep tables simple enough to read linearly;
+- avoid decorative Unicode that carries essential meaning without a text explanation;
+- avoid autoplaying audio/video or time-dependent interaction as required course content;
+- keep essential instructions available as plain text.
+
+## Diagrams
+
+ASCII or text diagrams are used throughout the course because they remain readable without image rendering.
+
+When a richer diagram is added, include a nearby text description that communicates the same learning point.
+
+Example:
+
+```text
+Car
+  └── has-a → Engine
+```
+
+The surrounding explanation should still state the relationship in words.
+
+## Notebooks
+
+Notebook cells should remain understandable when read from top to bottom.
+
+Authors should:
+
+- introduce the goal of a code cell before or immediately after it;
+- avoid making a screenshot the only source of required information;
+- keep learner TODO instructions in Markdown or comments;
+- avoid hidden setup steps;
+- preserve sequential execution.
+
+## Assessment accessibility
+
+Assessment quality should depend on understanding OOP concepts, not on visual speed or familiarity with a specific interface.
+
+Facilitators may adapt presentation or timing to learner needs as long as the assessed learning outcome is preserved.
+
+## Contributions
+
+Accessibility improvements are welcome. Use the repository issue templates or follow [CONTRIBUTING.md](CONTRIBUTING.md).

CHANGELOG.md

@@ -83,4 +83,10 @@ The GitHub Actions validation workflow passed on `main` after the audit and lear
 
 ## Unreleased
 
-Future changes should preserve the course progression, assessment guardrails, reference alignment, and self-paced/open-course neutrality described in the repository documentation.
+### Publication polish
+
+- added `CITATION.cff` so the repository has machine-readable citation metadata;
+- added `ACCESSIBILITY.md` with learner and contributor accessibility guidance;
+- added validation guards for citation/accessibility publication assets.
+
+Future changes should preserve the course progression, assessment guardrails, reference alignment, accessibility guidance, and self-paced/open-course neutrality described in the repository documentation.

CITATION.cff

@@ -0,0 +1,16 @@
+cff-version: 1.2.0
+message: "If you use this open course in teaching, training, research, or adapted learning materials, please cite it as below."
+title: "Object Oriented Programming — Open Course"
+type: software
+authors:
+  - family-names: "Muhammad"
+    given-names: "Bofandra"
+repository-code: "https://github.com/bofandra/oop-course"
+url: "https://github.com/bofandra/oop-course"
+abstract: "A self-paced open course for learning object-oriented thinking using Python, with executable notebooks, assessments, mastery checks, and a complete capstone."
+keywords:
+  - object-oriented-programming
+  - python
+  - open-course
+  - education
+  - jupyter-notebook

CONTRIBUTING.md

@@ -10,6 +10,7 @@ Read:
 - [Reference Map](REFERENCE_MAP.md)
 - [Assessment Alignment](ASSESSMENT_ALIGNMENT.md)
 - [Execution Audit](EXECUTION_AUDIT.md)
+- [Accessibility Guide](ACCESSIBILITY.md)
 
 ## Course design guardrails
 
@@ -22,6 +23,7 @@ Please preserve these principles:
 5. Keep learner-facing material self-paced and independent of institution-specific or fixed-calendar scheduling.
 6. Do not publish answer keys for assessments that may be reused by facilitated cohorts.
 7. Keep formal concepts aligned to the documented references.
+8. Preserve accessibility: essential meaning must not depend only on color, images, or a specific interface.
 
 ## Module changes
 
@@ -74,4 +76,5 @@ Confirm that:
 - Colab launch coverage remains complete;
 - reference mapping remains accurate;
 - learner-facing wording remains self-paced and institution-neutral;
+- new visuals have meaningful text alternatives and essential instructions remain text-accessible;
 - no assessment answer key has been published accidentally.

README.md

@@ -85,6 +85,7 @@ Open-course guidance:
 - [Reference Map](REFERENCE_MAP.md)
 - [Instructor Guide](INSTRUCTOR_GUIDE.md)
 - [Execution Audit](EXECUTION_AUDIT.md)
+- [Accessibility Guide](ACCESSIBILITY.md)
 - [Changelog](CHANGELOG.md)
 - [Grading Operational System](GRADING_SYSTEM.md)
 - [Gradebook Quick Start](GRADEBOOK_GUIDE.md)
@@ -211,6 +212,16 @@ Move to next module when ready
 
 Use the [Colab notebook index](COLAB.md) to launch the executable course notebooks directly in Google Colab. Save a personal copy, run the examples, complete the TODO cells, and compare your work against the stated requirements and rubrics.
 
+## Citation and reuse
+
+If you use or adapt this course for teaching, training, or research, use the repository's [citation metadata](CITATION.cff). GitHub can use this file to provide a **Cite this repository** action.
+
+For adapted instructional material, preserve appropriate attribution and follow the license terms below.
+
+## Accessibility
+
+See the [Accessibility Guide](ACCESSIBILITY.md) for learner guidance and content-authoring rules. Essential course instructions should remain available as text, and new visuals should include equivalent text descriptions.
+
 ## License
 
 Instructional materials are licensed under **Creative Commons Attribution 4.0 International (CC BY 4.0)** and code/software portions are licensed under the **MIT License**, except where otherwise noted. See [LICENSE.md](LICENSE.md).

scripts/validate_course.py

@@ -27,6 +27,8 @@ def required_structure(errors: list[str]) -> None:
     required = [
         "README.md",
         "CHANGELOG.md",
+        "CITATION.cff",
+        "ACCESSIBILITY.md",
         "COURSE_MAP.md",
         "OPEN_COURSE_GUIDE.md",
         "SELF_PACED_GUIDE.md",
@@ -395,6 +397,8 @@ def validate_publication_navigation(errors: list[str]) -> None:
             "REFERENCE_MAP.md",
             "SELF_PACED_GUIDE.md",
             "SELF_ASSESSMENT_GUIDE.md",
+            "ACCESSIBILITY.md",
+            "CITATION.cff",
             "CHANGELOG.md",
             "00-python-primer/readiness-check.md",
             "week-01/",
@@ -421,6 +425,35 @@ def validate_publication_navigation(errors: list[str]) -> None:
                 fail(errors, f"{path.name}: missing public navigation link to {link}")
 
 
+def validate_publication_metadata(errors: list[str]) -> None:
+    citation_path = ROOT / "CITATION.cff"
+    if citation_path.exists():
+        text = citation_path.read_text(encoding="utf-8")
+        required_fragments = [
+            "cff-version: 1.2.0",
+            'title: "Object Oriented Programming — Open Course"',
+            "authors:",
+            'family-names: "Muhammad"',
+            'given-names: "Bofandra"',
+            'repository-code: "https://github.com/bofandra/oop-course"',
+        ]
+        for fragment in required_fragments:
+            if fragment not in text:
+                fail(errors, f"CITATION.cff: missing required metadata fragment: {fragment}")
+
+    accessibility_path = ROOT / "ACCESSIBILITY.md"
+    if accessibility_path.exists():
+        text = accessibility_path.read_text(encoding="utf-8")
+        for heading in [
+            "# Accessibility Guide",
+            "## Learner guidance",
+            "## Content authoring rules",
+            "## Assessment accessibility",
+        ]:
+            if heading not in text:
+                fail(errors, f"ACCESSIBILITY.md: missing required section: {heading}")
+
+
 def validate_open_course_neutrality(errors: list[str]) -> None:
     forbidden_patterns = {
         "institution affiliation": re.compile(r"TANRI\s+ABENG", re.IGNORECASE),
@@ -553,6 +586,7 @@ def main() -> int:
     validate_module_colab_navigation(errors)
     validate_reference_map(errors)
     validate_publication_navigation(errors)
+    validate_publication_metadata(errors)
     validate_assessment_structure(errors)
     validate_public_assessment_safety(errors)
     validate_open_course_neutrality(errors)
@@ -580,6 +614,7 @@ def main() -> int:
     print("- direct module Colab navigation: OK")
     print("- reference-map coverage: OK")
     print("- publication navigation: OK")
+    print("- citation/accessibility metadata: OK")
     print("- assignment rubric / quiz structure: OK")
     print("- learner-facing assessment neutrality: OK")
     print("- public assessment-key guard: OK")