In 2025, financial privacy is under assault from all sides: data breaches, AI training on user data, government surveillance, and aggressive data monetization by financial institutions. Plain text accounting with Beancount represents a fundamentally different approach: privacy by default, control by design.
The Financial Privacy Crisis of 2025
The numbers are sobering:
Data Breaches in Financial Industry
According to IBM’s Cost of a Data Breach Report 2024, the average cost of a data breach in the financial sector is $5.56 million - the second highest of any industry.
Recent major breaches:
- 2024: Multiple credit card processors compromised
- 2023-2024: Banking aggregators (Plaid competitors) exposed user credentials
- 2024: Fintech startups leaked transaction histories
When your financial data lives in the cloud, you’re one breach away from:
Transaction history exposed (spending patterns, income, debts)
Account credentials stolen (bank logins, credit cards)
Personal information leaked (SSN, addresses, phone numbers)
Identity theft (fraudulent accounts opened in your name)
The AI Data Mining Problem
In 2025, financial companies are using your data to:
- Train AI models (your spending patterns = training data)
- Target advertising (personalized ads based on transactions)
- Sell insights to third parties (aggregated data sold to marketers)
- Develop products (your behavior shapes new financial products)
Example: You use a “free” budgeting app. It analyzes your data and discovers you:
- Shop at premium grocery stores → Targeted with luxury credit card ads
- Have student loans → Targeted with refinancing offers
- Spend on baby products → Targeted with life insurance, college savings plans
- Travel frequently → Targeted with travel credit cards, hotel memberships
This is surveillance capitalism applied to your finances.
The SaaS vs Self-Hosted Comparison
| Aspect | SaaS (Cloud) | Self-Hosted (Beancount) |
|---|---|---|
| Data location | Third-party servers | Your computer |
| Data access | Company has full access | Only you have access |
| Privacy policy | Can change anytime | You set the rules |
| Data breaches | High risk (centralized target) | Low risk (no cloud storage) |
| AI training | Your data may be used | Never (it’s private) |
| Government access | Via subpoena to company | Via warrant to you only |
| Data portability | Limited export options | Plain text (universal) |
| Encryption | TLS in transit, varies at rest | You control encryption |
| Vendor lock-in | High (proprietary formats) | None (open format) |
| Long-term access | Until company shuts down | Forever (plain text) |
Why Plain Text Accounting is Privacy-First
1. Local-First Architecture
With Beancount:
Your ledger file lives on YOUR computer
No cloud sync (unless you explicitly choose it)
No third-party servers see your data
No company can access, analyze, or sell your financial information
Example workflow:
# Your entire financial life in one file
~/Documents/finance/main.beancount
# Process it locally
bean-check main.beancount
# View it locally
fava main.beancount
# Your data NEVER leaves your machine
2. Encryption at Rest
You control how (and if) to encrypt your data:
Option 1: Encrypted filesystem (FileVault, BitLocker)
# macOS FileVault encrypts entire disk
# Your Beancount file is encrypted automatically
# Decrypt only when you log in
Option 2: Encrypted container (VeraCrypt)
# Create encrypted volume for sensitive files
veracrypt --create ~/finance.vc
veracrypt --mount ~/finance.vc /mnt/finance
# Work with files in /mnt/finance
veracrypt --dismount /mnt/finance
Option 3: GPG encryption
# Encrypt Beancount file with GPG
gpg --encrypt --recipient [email protected] main.beancount
# Decrypt when needed
gpg --decrypt main.beancount.gpg > main.beancount
# Process
bean-check main.beancount
# Re-encrypt
gpg --encrypt --recipient [email protected] main.beancount
rm main.beancount # Remove plaintext
With cloud services, you have ZERO control over encryption keys. The company can decrypt your data anytime.
3. No Telemetry, No Analytics, No Tracking
Cloud financial apps track EVERYTHING:
- How often you log in
- Which features you use
- How long you spend on each screen
- Which reports you generate
- Search queries you run
Beancount tracks: NOTHING.
- No phone-home
- No usage analytics
- No crash reports (unless you submit them manually)
- No A/B testing
- No behavioral tracking
Your usage patterns are YOUR business.
4. Selective Sharing
With cloud apps, you’re forced to share:
Everything with the company (they see all your data)
Data with third-party integrations (permissions required)
Aggregated data with partners (sold for revenue)
With Beancount, you share ONLY what you choose:
Share specific accounts with accountant (export subset)
Share anonymized data with family (remove sensitive details)
Share reports with investors (PDF exports only)
Keep everything else completely private
Example: Selective export for tax accountant
#!/usr/bin/env python3
"""
Export only tax-relevant accounts for CPA
"""
from beancount import loader
from beancount.core import getters
import sys
def export_tax_data(ledger_file, output_file):
"""Export only tax-related accounts"""
entries, errors, options = loader.load_file(ledger_file)
with open(output_file, 'w') as f:
for entry in entries:
# Only include tax-related entries
if hasattr(entry, 'account') and 'Tax' in entry.account:
f.write(str(entry) + '\n')
if __name__ == '__main__':
export_tax_data('main.beancount', 'tax_data.beancount')
print("âś… Tax data exported (everything else remains private)")
Your CPA sees ONLY tax-related accounts. Your personal spending, net worth, investment strategy? Private.
The Threat Models
Threat Model 1: Data Breach
Cloud SaaS scenario:
- Attacker breaches budgeting app database
- 10 million users’ transaction histories leaked
- Your spending patterns, account numbers, balances exposed
- Identity theft risk, embarrassment, financial fraud
Beancount scenario:
- Your ledger file is on your computer
- Attacker would need to:
- Compromise your specific computer (targeted attack)
- Bypass disk encryption
- Bypass login password
- Find and exfiltrate your ledger file
- Much harder than breaching a centralized database
Threat Model 2: Government Surveillance
Cloud SaaS scenario:
- Government subpoenas budgeting app company
- Company hands over all your data (they have no choice)
- No notification to you (often gagged by court order)
- Your financial history in government hands
Beancount scenario:
- Government must obtain warrant for YOUR specific computer
- You’re notified (unless sealed warrant)
- They get only what’s on your computer at that moment
- Much higher legal bar for access
Threat Model 3: Corporate Data Mining
Cloud SaaS scenario:
- Company analyzes your transactions
- Builds profile: income level, spending habits, life events
- Sells insights to advertisers, credit bureaus, insurance companies
- You can’t opt out (it’s in the TOS you didn’t read)
Beancount scenario:
- Your data never reaches any company
- No profile building
- No data selling
- Complete privacy by default
Threat Model 4: AI Training
Cloud SaaS scenario:
- Company feeds your transactions into LLMs
- AI learns from your financial patterns
- Your data (anonymized or not) trains commercial AI
- No compensation, no control, no opt-out
Beancount scenario:
- Your data stays on your machine
- Never used for AI training
- If you want AI assistance, use LOCAL LLMs (see earlier discussion)
Privacy Best Practices with Beancount
1. Air-Gapped Financial Management
Maximum security approach:
# Use a dedicated computer for finances
# Never connect it to the internet
# Transfer data via USB only
# On air-gapped computer:
bean-check main.beancount
fava main.beancount
# Export reports to USB
# Print or transfer to internet-connected computer for sharing
This is how high-security organizations handle sensitive data.
2. Git with Encrypted Repository
Balance privacy with version control:
# Create encrypted Git repository
git init ~/finance
cd ~/finance
# Configure git-crypt for transparent encryption
git-crypt init
git-crypt add-gpg-user your_gpg_key_id
# Add .gitattributes to encrypt Beancount files
echo "*.beancount filter=git-crypt diff=git-crypt" > .gitattributes
echo "*.bean filter=git-crypt diff=git-crypt" >> .gitattributes
# Commit as usual
git add main.beancount .gitattributes
git commit -m "Update ledger"
# Files are encrypted in Git, plaintext when checked out
Benefits:
Version control (track all changes)
Encrypted repository (even if someone steals .git folder)
Transparent encryption (work with plaintext, committed as encrypted)
3. Backup Strategy Without Cloud
Avoid cloud backup services (they can access your data):
# Option 1: Encrypted USB drives (multiple copies)
# Keep one at home, one at work, one at relative's house
# Option 2: Encrypted NAS (Network Attached Storage)
# On local network only, no internet access
# Option 3: Encrypted external HDD in safe deposit box
# Manual backup monthly
# Example: Automated encrypted backup to USB
#!/bin/bash
tar czf - ~/Documents/finance | gpg --encrypt --recipient [email protected] > /media/usb/finance_backup_$(date +%Y%m%d).tar.gz.gpg
4. Minimize Digital Footprint
Reduce attack surface:
# Don't sync ledger to cloud (Dropbox, Google Drive, iCloud)
# Don't email ledger files (unencrypted email is insecure)
# Don't use web-based editors (Google Docs, Office 365)
# Don't share via cloud file sharing services
# Instead:
# - Transfer via encrypted USB
# - Transfer via secure file transfer (scp, rsync over SSH)
# - Share encrypted exports only
Real-World Privacy Benefits
Case Study 1: Medical Expenses
Sensitive scenario: You have expensive medical treatments (mental health, fertility, chronic illness)
With cloud budgeting app:
Company sees all medical expenses
Potentially sold to health insurance data brokers
Could affect insurance rates or employment
Stigma if breached (mental health treatment exposed)
With Beancount:
Complete privacy
No third party ever sees this data
No insurance implications
No breach risk (local-only)
Case Study 2: Legal/Divorce Situations
Sensitive scenario: Going through divorce, need to document finances
With cloud budgeting app:
Spouse may have shared account access
Company could be subpoenaed by opposing counsel
Data might be used against you in court
No control over who sees what
With Beancount:
Complete control over access
Can create separate ledgers for different purposes
Share only specific accounts/periods with attorney
No third party has access to dispute
Case Study 3: Business Financial Strategy
Sensitive scenario: Small business owner planning expansion, acquisition, or sale
With cloud accounting (QuickBooks Online):
Intuit sees all financial data
Potentially sells insights to competitors
Data breach could expose business strategy
Required to use their cloud (no self-hosted option)
With Beancount:
Complete confidentiality
No risk of strategic information leaking
Share only what’s needed with investors/buyers
Full control over sensitive business data
The Cost of Privacy
Privacy isn’t free. What are you trading?
What you GAIN with Beancount:
Complete financial privacy
Data ownership and control
No surveillance or tracking
No data breaches (local-only)
No AI training on your data
No data monetization by companies
Future-proof format (plain text)
What you LOSE vs cloud apps:
Automatic bank syncing (must download CSVs manually)
Mobile app convenience (Fava works in browser, but not native app)
AI categorization (unless you run local LLMs)
One-click setup (learning curve required)
Is the trade-off worth it?
My answer: Absolutely.
I’d rather spend 15 minutes per week managing my finances privately than have my entire financial life analyzed, sold, and potentially breached by cloud companies.
The Philosophical Case for Privacy
“I Have Nothing to Hide”
This argument misses the point:
- You close bathroom door (but you’re not doing anything illegal)
- You use curtains on windows (but you’re not hiding crimes)
- You don’t post bank statements on social media (but you’re not ashamed)
Privacy isn’t about hiding wrongdoing. It’s about controlling your personal information.
“But Google/Facebook Already Know Everything”
Two wrongs don’t make a right:
- Just because some companies track you doesn’t mean ALL companies should
- Financial data is especially sensitive (affects credit, insurance, employment)
- You can reduce tracking incrementally (every bit helps)
“Encryption is Too Hard”
Modern tools make encryption easy:
- FileVault / BitLocker: One-click disk encryption
- GPG: Command-line, but straightforward
- Git-crypt: Transparent encryption for version control
The real question: Is your financial privacy worth 1 hour to set up encryption?
My Recommendation
Start with basic privacy:
- Use Beancount locally (no cloud sync)
- Enable disk encryption (FileVault/BitLocker)
- Back up to encrypted USB drives (not cloud)
Enhance privacy incrementally:
- Use GPG for ledger file encryption
- Set up air-gapped computer for finances
- Use Tor for any online banking (anonymize IP address)
- Use local LLMs for AI assistance (no data sent to OpenAI)
Maximum privacy (for the paranoid):
- Air-gapped computer (never connected to internet)
- Encrypted repository with git-crypt
- Hardware security keys (YubiKey for GPG)
- Physical security (safe for backup drives)
Questions for the Community
- How are you protecting your financial privacy?
- What encryption tools are you using with Beancount?
- Any concerns about privacy I haven’t addressed?
- Is anyone using air-gapped computers for financial management?
In 2025, financial privacy is a choice. Beancount lets you choose privacy.
Sources:
- IBM Cost of a Data Breach Report 2024 ($5.56M financial industry average)
- Data breach reports 2024-2025 (financial sector)
- Surveillance capitalism research
- Privacy engineering best practices
- My 8 years of privacy-focused financial management