Where the data comes from, and why you can trust it
evac.lt doesn’t make its own shelter lists or maps. It uses official and open sources, and packages them so they work without the internet.
Packs
The shelter data and the overview map are installed with the app. Everything else you download yourself – only what you need. Downloads are compressed; a pack takes more space once installed.
| Pack | Download | Licence |
|---|---|---|
| Maps with navigation and search | ||
| Overview map required The Baltics and Poland without streets; town and village search. | 86 MB | Map data © OpenStreetMap contributors, ODbL 1.0. Basemap: Protomaps. Routing: Valhalla. |
| Lithuania Street-level map of Lithuania, address search, walking and driving navigation. | 413 MB | Map data © OpenStreetMap contributors, ODbL 1.0. Basemap: Protomaps. Routing: Valhalla. |
| Latvia Latvia: map, addresses and navigation. | 333 MB | Map data © OpenStreetMap contributors, ODbL 1.0. Basemap: Protomaps. Routing: Valhalla. |
| Estonia Estonia: map, addresses and navigation. | 194 MB | Map data © OpenStreetMap contributors, ODbL 1.0. Basemap: Protomaps. Routing: Valhalla. |
| Poland Poland: map, addresses and navigation. | 1.7 GB | Map data © OpenStreetMap contributors, ODbL 1.0. Basemap: Protomaps. Routing: Valhalla. |
| Civil-protection data | ||
| Shelters, evacuation and sirens requiredpre-installedupdates itself Official PAGD data: shelters, collective protection buildings, evacuation points and sirens. | 546 KB | CC BY 4.0, PAGD / Valstybės duomenų agentūra. |
| Library | ||
| Official publications LT Ministry of National Defence and PAGD preparedness publications, the Vilnius evacuation plan. | 147 MB | See each document. |
| Survival manuals EN Survival, navigation and first aid manuals (US Army, Hesperian). | 56 MB | Mixed: US Government works (public domain) and documents licensed for free non-commercial redistribution; see each document. |
| Medicine EN Medical encyclopedia (MDWiki): conditions, injuries, drugs, procedures. | 385 MB illustrated: 1.5 GB | CC BY-SA 4.0, MDWiki and Wikipedia contributors. |
| Encyclopedia LT The whole Lithuanian Wikipedia. | 424 MB illustrated: 2.6 GB | CC BY-SA 4.0, Wikipedia contributors. |
| Travel and phrasebooks EN Travel guide: Poland, the Baltic and Nordic countries, Germany, phrasebooks, safety. | 11 MB | CC BY-SA 4.0, Wikivoyage contributors. |
| Appropriate technology EN Appropriate technology: water treatment, stoves, sanitation, food drying. | 81 MB illustrated: 347 MB | CC BY-SA 4.0, Appropedia contributors. |
| Off-grid energy EN Off-grid energy: solar power, fuels, cooking. | 22 MB | CC BY-SA 3.0, Energypedia contributors. |
Packs are hosted at packs.evac.lt (Cloudflare R2). The shelter, evacuation point and siren data is updated when PAGD changes it.
How the app checks that packs are genuine
Nobody – not a network middleman, not someone passing on a tampered file – should be able to change where the shelters are or what an article says.
A signed catalog
The list of packs carries an Ed25519 digital signature. The app checks it with a public key built into the app itself.
Every file is checked
The catalog lists a SHA-256 checksum for every file. A download that doesn’t match is not installed.
Even when shared offline
A shared pack carries a copy of the signed catalog, so the receiving app verifies it the same way – even if it’s an older version.
Public keys
Two keys: the primary one, and a backup kept separately in case the primary ever has to be replaced.
| Key | Public key (Ed25519, base64) |
|---|---|
evac-2026-a primary | ot7g5NQWnFNpXbVMeIt/jDggwz3yZWnaryF0tt0rioo= |
evac-2026-b | KfofuxNGvusZ6JbWzXEg6NUmcsNtnFmMDe+AcTKtn8o= |
Data sources
Thank you to everyone whose work makes this app possible.
- OpenStreetMap ODbL 1.0
Map data © OpenStreetMap contributors. The map, place search and routing packs are derived from OpenStreetMap data and are distributed under the Open Database License (ODbL) 1.0. See openstreetmap.org/copyright
- Protomaps BSD-3-Clause (style), ODbL (tiles)
Basemap tiles and style by Protomaps (protomaps.com), including Natural Earth data (public domain).
- PAGD – priedangos, evakavimo punktai, sirenos CC BY 4.0
Fire and Rescue Department under the Ministry of the Interior / State Data Agency, open data (open.geodata.gov.lt). Simplified for the app.
- LRT RADIJAS
Radio frequency list from LRT (apie.lrt.lt).
- Gidai ir sąrašai
Written from LT72.lt, PAGD, the Ministry of National Defence booklet, the Health Emergency Situations Centre and European Resuscitation Council (ERC) guidance. An unofficial summary.
- Wikipedia, WikiMed, Wikivoyage, Appropedia CC BY-SA 4.0
Content by the Wikipedia, MDWiki, Wikivoyage and Appropedia contributors under CC BY-SA 4.0. Converted from Kiwix / openZIM archives; changes: images and some formatting removed.
- Energypedia CC BY-SA 3.0
Content by the Energypedia contributors under CC BY-SA 3.0; images removed.
- Oficialūs leidiniai / Official publications
Public-information publications for citizens by the Lithuanian Ministry of National Defence (kam.lt) and the Fire and Rescue Department (PAGD, lt72.lt). Provided unmodified with their source; the latest versions are on kam.lt and lt72.lt.
- Išgyvenimo vadovai / Survival manuals
US Government publications (public domain) and documents licensed for free redistribution. Hesperian Health Guides books are used under their free, not-for-profit permission – thanks to Hesperian (hesperian.org). Each document shows its source and licence.
Essential places (hospitals, pharmacies, water and so on) come from OpenStreetMap – community data, not official, and possibly inaccurate or out of date. If you spot a mistake, you can fix it directly on openstreetmap.org.
Software
evac.lt is built on open-source libraries. The full licence texts are in the app, under “Settings → About and licences”.
- MapLibre Native – BSD-2-Clause
- MapLibre Native – third-party components – various
- Valhalla – MIT
- valhalla-mobile – MIT
- valhalla-openapi-models-swift – MIT
- AnyCodable – MIT
- Light-Swift-Untar – BSD-2-Clause
- Boost C++ Libraries (in Valhalla) – BSL-1.0
- Protocol Buffers (in Valhalla) – BSD-3-Clause
- Abseil (in Valhalla) – Apache-2.0
- LZ4 (in Valhalla) – BSD-2-Clause
- RapidJSON (in Valhalla) – MIT
- robin-hood-hashing (in Valhalla) – MIT
- unordered_dense (in Valhalla) – MIT
- Protomaps basemaps – BSD-3-Clause
- Noto Sans (map labels) – SIL Open Font License 1.1
- SQLite – Public domain
Hosting
The website and packs are hosted by Cloudflare (Pages and R2). Thank you for keeping them fast everywhere.