An interactive map showing where ~20,000 municipalities across 47 European countries host their official email — whether with US hyperscalers (Microsoft, Google, AWS), local/EU providers, or self-hosted solutions.
All 27 EU member states plus 20 non-EU European countries including Norway, Iceland, the United Kingdom, Switzerland's neighbours, the Western Balkans, and the Caucasus.
The data pipeline has three steps:
- Preprocess — Loads ~20,000 municipalities from curated seed data across 47 countries, performs MX, SPF, CNAME, DKIM, autodiscover, and TXT DNS lookups on their official domains (with domain guessing for missing entries), detects email security gateways (SeppMail, Barracuda, Hornetsecurity, etc.), and classifies each municipality's email provider. TXT domain verification tokens (e.g.,
MS=for Microsoft 365,google-site-verification=for Google Workspace) serve as tiebreakers when other signals are ambiguous. - Postprocess — Applies manual overrides for edge cases, retries DNS for unresolved domains, checks SMTP banners of independent MX hosts for hidden providers, then scrapes websites of still-unclassified municipalities for email addresses.
- Validate — Cross-validates MX and SPF records, assigns a confidence score (0–100) to each entry, and generates a validation report.
flowchart TD
trigger["Nightly trigger"] --> seed
subgraph pre ["1 · Preprocess"]
seed[/"Seed data (47 countries)"/] --> fetch["Load ~20,000 municipalities"]
fetch --> domains["Extract domains +<br/>guess candidates"]
domains --> dns["MX + TXT lookups<br/>(3 resolvers)"]
dns --> spf_resolve["Resolve SPF includes<br/>& redirects"]
spf_resolve --> cname["Follow CNAME chains"]
cname --> asn["ASN lookups<br/>(Team Cymru)"]
asn --> autodiscover["Autodiscover DNS<br/>(CNAME + SRV)"]
autodiscover --> dkim["DKIM selector<br/>CNAME lookups"]
dkim --> gateway["Detect gateways<br/>(SeppMail, Barracuda,<br/>Proofpoint, Sophos ...)"]
gateway --> classify["Classify providers<br/>MX → CNAME → SPF →<br/>Autodiscover → DKIM → TXT"]
end
classify --> overrides
subgraph post ["2 · Postprocess"]
overrides["Apply manual overrides"] --> retry["Retry DNS<br/>for unknowns"]
retry --> smtp["SMTP banner check<br/>(EHLO on port 25)"]
smtp --> scrape_urls["Probe municipal websites<br/>(/kontaktid, /kontakti, /kontaktai …)"]
scrape_urls --> extract["Extract emails<br/>+ decrypt TYPO3 obfuscation"]
extract --> scrape_dns["DNS lookup on<br/>email domains"]
scrape_dns --> reclassify["Reclassify<br/>resolved entries"]
end
reclassify --> data[("data.json")]
data --> score
subgraph val ["3 · Validate"]
score["Confidence scoring · 0–100"] --> gwarn["Flag potential<br/>unknown gateways"]
gwarn --> gate{"Quality gate<br/>avg ≥ 70 · high-conf ≥ 80%"}
end
gate -- "Pass" --> deploy["Commit & deploy to Pages"]
gate -- "Fail" --> issue["Open GitHub issue"]
style trigger fill:#e8f4fd,stroke:#4a90d9,color:#1a5276
style seed fill:#e8f4fd,stroke:#4a90d9,color:#1a5276
style data fill:#d5f5e3,stroke:#27ae60,color:#1e8449
style deploy fill:#d5f5e3,stroke:#27ae60,color:#1e8449
style issue fill:#fadbd8,stroke:#e74c3c,color:#922b21
style gate fill:#fdebd0,stroke:#e67e22,color:#935116
uv sync
uv run preprocess
uv run postprocess
uv run validate
# Serve the map locally
python -m http.serveruv sync --group dev
# Run tests with coverage
uv run pytest --cov --cov-report=term-missing
# Lint the codebase
uv run ruff check src tests
uv run ruff format src testsThis project is a fork of mxmap.ch by David Huser, which maps email providers of Swiss municipalities. Adapted for 47 European countries with region-specific provider detection (Telia, TET, Zone.eu, local ISPs), gateway look-through (SeppMail, Barracuda, Hornetsecurity, etc.), DKIM/TXT verification-based classification, curated seed data, and per-country TopoJSON geodata.
- mxmap.ch — the original Swiss municipality email provider map
- hpr4379 :: Mapping Municipalities' Digital Dependencies
- If you know of similar projects for other countries, please open an issue or submit a PR!
If you spot a misclassification, please open an issue with the municipality ID and the correct provider.
For municipalities where automated detection fails, corrections can be added to the MANUAL_OVERRIDES dict in src/mail_sovereignty/postprocess.py.