Post mortem written on January 11, 2021

tl;dr: Someone found an exploit to create bitcoin (on the Autobahn Network) via double spend and tried to cash them out of the pool but only managed to obtain BTC worth 50$. We fixed the problem and froze the attackers accounts.

On Thursday evening, January 07, a user reported, that he had not received the bitcoin transaction from his withdrawal in the Autobahn Network. On Friday morning the core-team started investigating. …

The Autobahn Network delivers a novel way to move other assets on the network that is used by Tixl, which offers speed and privacy. In contrast to existing solutions we don’t rely on peer to peer payment channels, nor on centralized solutions to swap tokens.

Photo by Christian on Unsplash

The basic idea is to send the native tokens (we will use Bitcoin as the example for all assets in the following) to the address of a decentralized committee that stores the Bitcoins safely until they are withdrawn from the Autobahn Network. This is achieved by giving a subset of all validators, called the committee…


*** Update: In a token split done in 2020, MTXLT became TXL with a split ratio of 1:1,000. The MTXLT mentioned in this article migrated to TXL.***

!!! Notice !!!

The Tixl Testnet Blankenese is not yet released, but will be released soon! The deposit will work as soon as the new version is released!

With the release of the Tixl Testnest Blankenese comes the feature to send and receive Bitcoin. We wrote you a guide how to simply get some testnet bitcoin so you can transfer them to your Tixl wallet.

An online wallet

The easiest way to get a wallet for testnet bitcoins…

In this article we’ll briefly outline our progress and milestones for the Tixl prototype.

Photo by Capturing the human heart. on Unsplash


Validator node: A node running the consensus and storing the transactions in the ledger. Accepts transactions.
Gateway: The gateway accepts transactions and forwards them to all known validators.
Ledger: The ledger is the sum of all transactions and implements the Tixl DAG.
Consensus: An algorithm that is used to sync and validate the state (transactions) between all participants (validators).
Explorer: A website where you can see all transactions, approved by the network.

The road so far

We’re documenting our progress in this github repository. To summarise: We’ve already built a…

*** Update: In a token split done in 2020, MTXLT became TXL with a split ratio of 1:1,000. The MTXLT mentioned in this article migrated to TXL.***

In this post we announce how we determined who gets a share of the Airdrop of the Binance DEX AMA and the winners of the best questions!

Update: We updated the winning mechanism of section 2.

Photo by Josh Appel on Unsplash

Our top 5 questions:

What is the Consensus Algorithm used in Tixl and How was it Picked ?

What applications for the Tixl are you working on at the moment and, in your opinion, what is going to be the first…

Cryptocurrencies are decentralized, so there are many participants (or nodes, or validators), that validate the transactions. The sum of transactions constitutes the ledger and is replicated to all participating nodes. But how do they agree, which transactions happend? In Bitcoin this is decided by calculation power, but consensus protocols like the Stellar Consensus Protocol (SCP) can also be used to achieve the same goal. This article explains a basic building block of SCP, the Federated Byzantine Agreement System (FBAS) or ‘federated voting’ to enable synchronisation of the distributed ledger.

Byzantine Agreement

In consensus protocols, the goal is to get all nodes to…

Initial release documentation and explanation for the new serverless benchmark on .

Maybe you stumbled upon my first benchmark on Medium, that I released half a year ago. In the last weeks I have been working on a newer and better version of this benchmark. It aims to deal with the shortcomings of the first version. The methods of measuring requests have been improved and more rigor has been applied to both data collection and evaluation.

First of all the benchmark is now continuous, which means that the actual benchmark is executed every hour (for now) and the aggregated data over a larger span of time is used for the evaluation. Also…

The Honey Badger BFT is a consensus algorithm for asynchronous environments. Most consensus algorithms rely on a synchronous networks and elect a leader. Honey Badger is especially suitable for application for blockchains, as it makes progress even under highly adverse conditions. As I first read the paper, I quickly realized that my university din’t prepare me for such an elaborate algorithm, even the lecture on cryptography and distributed systems didn’t provide all the necessary basics for understanding that algorithm. After a week of reading around in different papers and source code I now think, that I have a superficial understanding…

Important Note: Deprecated

I released a newer and more reliable benchmark on this site.

We have Serverless around for almost four years now, since Amazon introduced it on the re:Invent in the end of 2014. In 2016 Google, Microsoft and IBM joined the party. While there is no big difference in pricing, when comparing those 4 major providers, there is a difference in delivered performance, as the following benchmark will show you.

At the end of the article you will find information how you can help me with collecting more data to provide more thorough research and insights about Serverless.

Experiment setup

To benchmark the…

This tutorial is targeted at coders, with at least some experience in React and Solidity. It will guide step by step through the smart contract and point out the specifics of an Ethereum react app.

Photo by Tobias Moore on Unsplash

The goal of this tutorial is to build a fictional market place on the blockchain for advertisements. As a user you can create tokens, that represent ad space on your website. Other users then can buy the token for an amount of ETH, specified by you, to take ownership of the token and define the content of the advert. If you’re just interested in the code, you can find the repository containing the whole application here.


Firstly, if you don’t have any experience with Solidity, the programming language for implementing smart contracts on the Ethereum blockchain, I recommend you to…

Bernd Strehl

Tixl, serverless, DevOps mindest, DApps, Node.js & Beer 🍺

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