diff --git a/.gitignore b/.gitignore
index b7faf40..f2e693a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -205,3 +205,6 @@ cython_debug/
 marimo/_static/
 marimo/_lsp/
 __marimo__/
+
+# macOS specific files
+.DS_Store
\ No newline at end of file
diff --git a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/.gitignore b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/.gitignore
index f38b114..8fac120 100644
--- a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/.gitignore
+++ b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/.gitignore
@@ -1,208 +1,82 @@
-# Byte-compiled / optimized / DLL files
+# Environment variables and secrets
+.env
+.env.local
+.env.*.local
+*.key
+*.pem
+secrets/
+*.secret
+
+# Virtual environments
+.venv/
+venv/
+env/
+ENV/
+.ENV/
+virtualenv/
+.virtualenv/
+
+# Python cache and compiled files
 __pycache__/
-*.py[codz]
+*.py[cod]
 *$py.class
-
-# C extensions
 *.so
-
-# Distribution / packaging
 .Python
-build/
-develop-eggs/
-dist/
-downloads/
-eggs/
-.eggs/
-lib/
-lib64/
-parts/
-sdist/
-var/
-wheels/
-share/python-wheels/
 *.egg-info/
-.installed.cfg
+dist/
+build/
 *.egg
-MANIFEST
-
-# PyInstaller
-#  Usually these files are written by a python script from a template
-#  before PyInstaller builds the exe, so as to inject date/other infos into it.
-*.manifest
-*.spec
 
-# Installer logs
-pip-log.txt
-pip-delete-this-directory.txt
+# uv
+uv.lock
+.uv/
+
+# IDE and editor files
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.DS_Store
+*.sublime-project
+*.sublime-workspace
+
+# OS files
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+Desktop.ini
+
+# Logs
+*.log
+logs/
+*.log.*
 
-# Unit test / coverage reports
+# Temporary files
+*.tmp
+*.temp
+.cache/
+.pytest_cache/
+.coverage
 htmlcov/
 .tox/
-.nox/
-.coverage
-.coverage.*
-.cache
-nosetests.xml
-coverage.xml
-*.cover
-*.py.cover
-.hypothesis/
-.pytest_cache/
-cover/
-
-# Translations
-*.mo
-*.pot
-
-# Django stuff:
-*.log
-local_settings.py
-db.sqlite3
-db.sqlite3-journal
 
-# Flask stuff:
-instance/
-.webassets-cache
-
-# Scrapy stuff:
-.scrapy
-
-# Sphinx documentation
-docs/_build/
-
-# PyBuilder
-.pybuilder/
-target/
+# Vercel
+.vercel
 
 # Jupyter Notebook
 .ipynb_checkpoints
 
-# IPython
-profile_default/
-ipython_config.py
-
 # pyenv
-#   For a library or package, you might want to ignore these files since the code is
-#   intended to run in multiple environments; otherwise, check them in:
-# .python-version
-
-# pipenv
-#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
-#   However, in case of collaboration, if having platform-specific dependencies or dependencies
-#   having no cross-platform support, pipenv may install dependencies that don't work, or not
-#   install all needed dependencies.
-#Pipfile.lock
+.python-version
 
-# UV
-#   Similar to Pipfile.lock, it is generally recommended to include uv.lock in version control.
-#   This is especially recommended for binary packages to ensure reproducibility, and is more
-#   commonly ignored for libraries.
-#uv.lock
+# Student responses (if storing locally)
+student_responses.txt
+*.txt.bak
 
-# poetry
-#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
-#   This is especially recommended for binary packages to ensure reproducibility, and is more
-#   commonly ignored for libraries.
-#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
-#poetry.lock
-#poetry.toml
-
-# pdm
-#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
-#   pdm recommends including project-wide configuration in pdm.toml, but excluding .pdm-python.
-#   https://pdm-project.org/en/latest/usage/project/#working-with-version-control
-#pdm.lock
-#pdm.toml
-.pdm-python
-.pdm-build/
-
-# pixi
-#   Similar to Pipfile.lock, it is generally recommended to include pixi.lock in version control.
-#pixi.lock
-#   Pixi creates a virtual environment in the .pixi directory, just like venv module creates one
-#   in the .venv directory. It is recommended not to include this directory in version control.
-.pixi
-
-# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
-__pypackages__/
-
-# Celery stuff
-celerybeat-schedule
-celerybeat.pid
-
-# SageMath parsed files
-*.sage.py
-
-# Environments
-.env
-.envrc
-.venv
-env/
-venv/
-ENV/
-env.bak/
-venv.bak/
-
-# Spyder project settings
-.spyderproject
-.spyproject
-
-# Rope project settings
-.ropeproject
-
-# mkdocs documentation
-/site
-
-# mypy
-.mypy_cache/
-.dmypy.json
-dmypy.json
-
-# Pyre type checker
-.pyre/
-
-# pytype static type analyzer
-.pytype/
-
-# Cython debug symbols
-cython_debug/
-
-# PyCharm
-#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
-#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
-#  and can be added to the global gitignore or merged into this file.  For a more nuclear
-#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
-#.idea/
-
-# Abstra
-# Abstra is an AI-powered process automation framework.
-# Ignore directories containing user credentials, local state, and settings.
-# Learn more at https://abstra.io/docs
-.abstra/
-
-# Visual Studio Code
-#  Visual Studio Code specific template is maintained in a separate VisualStudioCode.gitignore 
-#  that can be found at https://github.com/github/gitignore/blob/main/Global/VisualStudioCode.gitignore
-#  and can be added to the global gitignore or merged into this file. However, if you prefer, 
-#  you could uncomment the following to ignore the entire vscode folder
-# .vscode/
-
-# Ruff stuff:
-.ruff_cache/
-
-# PyPI configuration file
-.pypirc
-
-# Cursor
-#  Cursor is an AI-powered code editor. `.cursorignore` specifies files/directories to
-#  exclude from AI features like autocomplete and code analysis. Recommended for sensitive data
-#  refer to https://docs.cursor.com/context/ignore-files
-.cursorignore
-.cursorindexingignore
-
-# Marimo
-marimo/_static/
-marimo/_lsp/
-__marimo__/
-.vercel
+# macOS specific files
+.DS_Store
\ No newline at end of file
diff --git a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/README.md b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/README.md
index 66ba023..748e943 100644
--- a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/README.md
+++ b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/TreatOrHell/README.md
@@ -2,6 +2,9 @@
 
 ## <h1 align="center" id="heading"> 🎁 TreatOrHell App — Holiday Edition</h1>
 
+### About This Project
+This is a complete FastAPI application demonstrating production-ready deployment patterns with Vercel. It showcases character-based LLM interactions (St. Nicholas, Angel, and Devil) using OpenAI's Chat Completions API, environment variable management, and serverless deployment configuration.
+
 A FastAPI app that lets you chat with St. Nicholas, an Angel, or a Devil using the OpenAI Chat Completions API. Each character has their own unique personality and response style!
 
 ### Quick Start
@@ -15,6 +18,8 @@ uv run uvicorn api.index:app --reload --host 0.0.0.0 --port 8000
 
 Open http://localhost:8000
 
+**Note:** A `.gitignore` file is included to protect your `.env` file and API keys from being committed to version control. Always store sensitive credentials in `.env` files, never commit them to git.
+
 ## Run locally
 
 ### Option A: Using uv (recommended)
diff --git a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/.gitignore b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/.gitignore
new file mode 100644
index 0000000..eb08d81
--- /dev/null
+++ b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/.gitignore
@@ -0,0 +1,150 @@
+# Environment variables
+.env
+.envrc
+
+# Python virtual environments
+.venv
+venv/
+env/
+ENV/
+env.bak/
+venv.bak/
+
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+.python-version
+
+# UV
+uv.lock
+
+# PDM
+.pdm-python
+.pdm-build/
+
+# PEP 582
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# VS Code
+.vscode/
+
+# Ruff cache
+.ruff_cache/
+
+# Cursor
+.cursorignore
+.cursorindexingignore
+
+# macOS
+.DS_Store
diff --git a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/README.md b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/README.md
index 6fbfdf3..21fcd8d 100644
--- a/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/README.md
+++ b/Session_02_Back_End_Web_App_Development_&_Deployment_of_LLM_Applications/sample_backend_scripts/README.md
@@ -5,6 +5,9 @@
 
 ## <h1 align="center" id="heading"> 🎁 TreatOrHell App — Holiday Edition LLM App Variants</h1>
 
+### About This Project
+This folder contains progressive FastAPI examples demonstrating backend development concepts from basic HTML rendering to LLM-powered applications with document processing. Each step builds on the previous, teaching FastAPI routing, LLM integration (OpenAI), and file upload handling through holiday-themed examples.
+
 This repo contains a few minimal FastAPI examples that progress from a basic HTML page to an LLM-backed UI with document upload. Features St. Nicholas, Angel, and Devil characters for holiday-themed interactions. Keep the vibe, keep it simple.
 
 Our deployed Vercel applications are here: 
@@ -22,6 +25,8 @@ export OPENAI_API_KEY=sk-...   # required for LLM variants
 # Or create a .env file with: OPENAI_API_KEY=sk-...
 ```
 
+**Note:** A `.gitignore` file is included to protect your `.env` file and API keys from being committed to version control. Always store sensitive credentials in `.env` files, never commit them to git.
+
 ### App Variants (FastAPI)
 
 - **STEP0_app_html.py** - TreatOrHell Meter