Folder Organization

Folder Organization Best Practices

Expert guidance for organizing project directories, establishing file naming conventions, and maintaining clean, navigable project structures for research and development work.

When to Use This Skill

• Setting up new projects
• Reorganizing existing projects
• Establishing team conventions
• Creating reproducible research structures
• Managing data-intensive projects

Core Principles

1. Predictability - Standard locations for common file types
2. Scalability - Structure grows gracefully with project
3. Separation of Concerns - Code, data, documentation, outputs separated
4. Discoverability - Easy for others (and future you) to navigate
5. Version Control Friendly - Large/generated files excluded appropriately

Quick Reference: Standard Project Structure

Use the structure matching your project type. Full templates in project-structures.md.

Research/Analysis: data/{raw,processed,external}, notebooks/, src/, scripts/, tests/, docs/, results/, config/

Development: src/package_name/, tests/, docs/, examples/, .github/workflows/

Bioinformatics: data/{raw,reference,processed}, workflows/, config/, scripts/, results/, logs/

Data Analysis with Notebooks: notebooks/, figures/, data/, tests/, scripts/, docs/, archives/

Add MANIFEST.md files for token-efficient navigation (see manifest-system.md).

File Naming Rules

Detailed conventions in naming-conventions.md. Key rules:

1. Use lowercase with hyphens or underscores (not spaces or CamelCase)
2. Be descriptive but concise - process-telomere-data.py not script.py
3. Use consistent separators - hyphens for files, underscores for Python modules
4. Include version/date for important outputs - report-2026-01-23.pdf
5. Zero-pad sequences - 01-exploration.ipynb, 02-analysis.ipynb
6. Standardize session notes in session-saves/ directory

Version Control

DO commit: Source code, documentation, config files, small test data (<1MB), requirements files, READMEs

DON'T commit: Large data files, generated outputs, environment dirs, logs, temp files, API keys/secrets

.gitignore Template

# Claude Code
.claude/

# Python
__pycache__/
*.py[cod]
.venv/
venv/

# Jupyter
.ipynb_checkpoints/

# Data
data/raw/
data/processed/
*.fastq.gz
*.bam

# Outputs
results/
outputs/
*.png
*.pdf

# Logs & Environment
logs/
*.log
.env
.DS_Store

Data Organization

• Never modify raw data - keep originals in data/raw/ (read-only if possible)
• Document data provenance (source, download date)
• Use hierarchy: raw/ -> interim/ -> processed/ -> external/

Common Anti-Patterns

Avoid these patterns:

• Flat structure: Everything in root directory with no organization
• Ambiguous naming: notebook1.ipynb, test.ipynb, analysis_new.ipynb
• Mixed concerns: Data files and output images inside src/ directory

Deprecation Strategy

Deprecate rather than delete to maintain history and recovery options. Full guide in deprecation-guide.md.

Key pattern:

1. Create deprecated/ subdirectory with descriptive name
2. Move old files there
3. Write README.md explaining what, when, why, and how to recover
4. For scattered deprecated dirs, consolidate to single root deprecated/

Project Reorganization

Full systematic guide in reorganization-guide.md. Critical steps:

1. Update all file paths in scripts and notebooks after moving files
2. Search for references: grep -r "\.json\|\.csv\|\.png" --include="*.ipynb" --include="*.py"
3. Verify file counts match expectations (no files lost)
4. Remove temp files (.bak, .ipynb_checkpoints)
5. Test that notebooks/scripts still run correctly

Documentation Standards

Full guide in documentation-organization.md. Key points:

• Every project needs a README with: description, installation, usage, structure, data, results
• After major changes, create dated summary documents
• Consolidate scattered docs into documentation/ directory
• Keep only README.md, LICENSE, .gitignore in project root

MANIFEST System

Token-efficient project navigation system. Full documentation in manifest-system.md.

• Provides 85-90% token reduction for session startup
• Root MANIFEST.md gives complete project overview in ~1,500 tokens
• Subdirectory MANIFESTs for data/, figures/, scripts/, documentation/
• Update at end of every session with /update-manifest

Project Cleanup: Identifying Essential Files

Detailed process in deprecation-guide.md (section "Project Cleanup"). Summary:

1. Analyze notebooks to find referenced figures
2. Map figures to generating scripts
3. Move unused files to deprecated/ with descriptive subdirectory names
4. Document what was kept in MINIMAL_ESSENTIAL_FILES.md
5. Verify notebooks still work with cleaned structure

Integration with Other Skills

• python-environment - Environment setup and management
• claude-collaboration - Team workflow best practices
• jupyter-notebook-analysis - Notebook organization standards
• data-backup - Backup system should include MANIFESTs
• project-sharing - Include MANIFESTs in shared packages

Quick Setup

# Create standard research project structure
mkdir -p data/{raw,processed,external} notebooks scripts src tests docs results config
touch README.md .gitignore environment.yml

Supporting Files

References and Resources

• Cookiecutter Data Science
• A Quick Guide to Organizing Computational Biology Projects
• Good Enough Practices in Scientific Computing