Winding Tree Hackathon Report

Jan Hanák
Siesta Cloud
Published in
8 min readJul 12, 2019


As we wrote in the last article, we attended the Winding Tree #HackTravel hackathon which took place from 3rd to 5th July 2019 in Lisbon, Portugal.

Sintra and West coast road trip

We booked our flights two days before the HackTravel, to explore part of Portugal. We rented a car for a day and visited the western coast and the Sintra area. We have visited Palace of Pena, Capela de Nossa Senhora da Penha, Praia da Adraga and Praia das Azenhas do Mar. Our trip was amazing, all of the locations were really unique, but unfortunately, it was pretty cloudy.

Palace of Pena | Misty forest | Praia das Azenhas do Mar

Business hacking

Day One of TravelHack was business-oriented. The idea was to form teams and brainstorm new ideas and business models, which are enabled thanks to decentralized travel inventory data distribution.

We also presented our tutorial for uploading the hotel data to the Winding Tree.

In a Challenge of Business “hacking”, we joined forces with Sean from Tugo and brainstormed an idea about 0% OTA (Online Travel Agency) with travel insurance.

Zero commission OTA (Online Travel Agency) with insurance services-abstract

Easy access to an immense inventory of travel data can allow new business models to appear. If we combine an OTA generator with a travel insurance company we can create new OTAs with 0% commissions which will profit on upselling their insurance products.

Major OTAs already do this, for instance, Expedia upsells coverage for their trips through AIG. This enables travelers to be covered regardless of the cancellation policies of the providers they book their trips with.
In the future, the insurance products could be stored on the blockchain in a standardized manner, so anyone could buy or upsell them with other services.


Imagine you are booking a trip to go skiing with your friends in the Alps for a week. You had a bad experience in the past because you broke your leg one day before departing on your trip, so this time you want to buy insurance if this or anything else happens you get refunded for the cost of your entire trip (flight, hotel, rentals, lift tickets, etc.).
You also have an experience that on the portal they have on average 7% lower prices than on and they offer additional information about the equipment of the hotel for skiers, so you want to book your trip there.

Particular use-case

Combination of Siesta Cloud OTA generator and TuGo travel insurance company can offer various travel agencies to create their own travel portals with additional insurance products for booking. Their commission can be nominal or eliminated entirely because their primary profit will be made from commissions generated from insurance sales, which allows them to compete with major OTAs on price.

Winding Tree Business Hackathon proposal by Siesta Cloud and TuGo

Winding Tree announcing new features!

The next day there were presentations from the Winding Tree Team about decentralization and new concepts. Our CEO of Siesta Cloud, Mikolas Belec, presented our vision of “small and medium travel businesses in the age of blockchain” and we heard a great presentation about the research of blockchain utilization in the travel industry from Peakwork.

Mikolas Belec talking about small and medium travel businesses in the age of blockchain.

Later on, the Winding Tree developers team pulled out their “big guns” and showed new features related to trust and identity verification. They revealed a new role of organization, which has various features to increase trust, for example, LIF token deposit or domain verification. Support of other data formats, various trust clues, and new travel data segmentation was also introduced.

All these new features are well documented and described on

In our opinion, this new identity & trust features are the final pieces of mosaic which are necessary to implement for real-world usage od the Winding Tree. We are looking forward to implementing it into our product and to become a trusted entity in the Winding Tree ecosystem.

An explanation of new features and live coding, performed by Jiri, showed everyone how simple it is to use it. Afterward, Hacking challenges were announced.


Our team decided to pursue the following challenges in a single project:

#7 Website verification
#6 Receive bookings
#2 Sell a room
#1 Blockchain-based Metasearch

We wanted to play a bit with hardware, so we brought a Google Home Assistant device. We implemented Winding Tree hotel search in the voice assistant API to search for a hotel in a particular city and booking ability with Siesta Cloud as booking endpoint. As a bonus, we implemented a trust clue for the booking sender-signing by our HTTPS certificate.


Verified Winding Tree voice assistant

We used Google Home Voice Assistant to search for hotels in a particular city using Winding Tree read. We also used it to list hotels, choosing one with the dates to create a booking. We Signed the booking with the private key of SSL certificate of a particular domain. Composed the Winding Tree booking object and attached the signature as header to the booking request. We Received booking and got the public key out of domain SSL certificate and checked the signature of booking object.

Team Members

  • David Duong
  • Jan Hanák
  • Mikolas Belec



We wanted to explore the possibilities of voice assistant and use it for search and booking of accommodation of Winding Tree inventory. We haven’t worked with the Google voice assistant before, so we had to learn the API and features. We used libraries from the previous hackathon for connection to Winding Tree and composed a booking object. We used our SSL certificate private key to sign a hash of booking object, so the receiving party can verify the origin of booking from our domain. However the trust clue mechanism we did not finish due lack of time.

Screenshot of Verified Winding Tree voice assistant


  • Booking hotel without OTA
  • Trust clue: domain verification via SSL certificate


  1. Implementation of Google Home Voice Assistant dialog flow API > Listening for the city input.
  2. Searching in Winding Tree (using WT read API) for hotels in a particular city.
  3. Reading the found hotels
  4. Selecting hotel and dates
  5. Composing WT booking object, hashing, and signing by verified domain SSL certificate private key
  6. Sending a booking to WT booking API endpoint
  7. Receiving booking and fetching public key of the verified domain
  8. Checking the validity of the signature with the domain public key

We learned

  1. Google Home API / Dialog is not that easy
  2. The signatures and hashes should be in headers so the content of the request always correspond to the signature
  3. Various SSL certificate formats
  4. Searching by city and WT read filter params

Pitching and the results

It was really fun to pitch the voice assistant, we performed searching, booking and receiving a reservation without any problems. Then we tried to search for hotels in a different city, which resulted in reading a long list of hotels stored in Winding Tree located in New York, and the only way to stop it was to plug out the power cable :-).

We ended up at a 3rd place and we are really happy about that!

The winning projects implemented very useful toolkits for organization development, debugging and trust verification. We will definitely use these new tools for further development! Well done guys!

HackTravel by Winding Tree

Guest House Foreign Friend

As we wrote before, we made a deal with a local Guest House Foreign Friend a few weeks before the HackTravel. Joao and Fatima were lovely hosts and they gave us great tips for hidden gems in the Lisbon area, we also had a great discussion about the business environment in Portugal.

In exchange for accommodation, we have listed their property to Siesta PMS, hosted their inventory in Siesta Cloud and connected to Winding Tree testnet.

By performing this real-world use case, we demonstrate that it is possible for various roles in the travel ecosystem to share their assets and exchange values with each other.

But mainly, that it is easy and possible for a small accommodation business to do a fast and cheap tech upgrade to the latest hospitality technology and offer their inventory in a decentralized manner.

And this is just a beginning, there are millions of rooms yet to be connected.

We totally recommend Foreign Friend Guest House! It’s really cozy with a family atmosphere and we are definitely coming back there one day.

Farewell Lisbon

We really enjoyed Lisbon area as well as hacking, networking and learning new stuff.

Siesta Cloud team

Some amazing photos from our developer and photographer David.

Elevador da Bica, Streets of Lisbon, View from Lx Factory


Sadly, this HackTravel had fewer participants then it would deserve. Probably because in summer, developers are more focused on vacations rather than coding. Anyway, we learned a lot, met new friends and business partners!

The announced new features look really useful. We are looking forward to implementing them to Siesta Cloud soon. Also, we might polish the voice assistant and release it to production, so anyone will be able to search and book in Winding Tree using just voice!

As Jakub told during the speech, the Winding Tree is comparable to the internet. If you think about it, once the computer was invented, the invention of the internet was inevitable. It wasn’t a question of if it will be invented and adopted anymore, but when. The same story is with the decentralization of data in the travel industry, thanks to blockchain its not question if it will happen, but when. And we are proud to be part of this transformation.

Thanks, Winding Tree for the organization of this event, and Adel Ecosystem Ltd. for the community support of this project.

See you on next HackTravel!



Jan Hanák
Siesta Cloud

Project manager at Siesta Cloud, traveller and water sports enthusiast