Lethe

Data anonymization CLI for structured files and SQL dumps. Scan for PII with compliance framework mapping, then anonymize using Presidio and spaCy NER with Faker-generated replacements that stay consistent across your dataset.

Lethe performs pseudo-anonymization: PII is replaced with realistic fake values, preserving data structure and relationships. This is different from true anonymization, which irreversibly removes personal data. See Architecture docs for the full distinction and GDPR implications.

Install

pip install lethe-cli
python -m spacy download en_core_web_trf

For a faster, lighter model instead of the transformer:

python -m spacy download en_core_web_sm

Usage

Scan

Analyze a file for PII and map findings to compliance frameworks (GDPR, HIPAA, CCPA, PCI-DSS, SOX, FERPA). No data is modified.

lethe scan data.csv                    # quick scan with Rich report
lethe scan data.csv --json             # machine-readable JSON output
lethe scan data.csv --model trf        # accurate transformer model

Anonymize

Replace detected PII with consistent fake values:

lethe anonymize data.csv -o anonymized.csv
lethe anonymize data.csv --model sm --threshold 0.7
lethe anonymize notes.txt -o clean.txt --locale nl_NL

Multiply

Generate synthetic rows from an existing dataset:

lethe multiply data.csv --factor 5 -o expanded.csv
lethe multiply data.csv --factor 10 --sanitize --seed 42

Options

Run lethe scan --help, lethe anonymize --help, or lethe multiply --help for the full list of options.

License

MIT