Some Comments on the Security of ECIES with secp256k1

The challenge of modern cryptography is to find efficient but secure encryption schemes. The Elliptic Curve Integrated Encryption Scheme (ECIES) is a widely used encryption scheme which is specified in many standards. It is used for example in Ethereum’s Whisper. While Bitcoin Core does not implement ECIES, it can be employed to send secure messages […]

Interdependent Transactions in Bitcoin, RSK and Ethereum

A recent paper titled The Blockchain Anomaly presents the difficulties the authors encountered when trying to make two transactions interdependent such that the second transaction cannot be executed without the first being confirmed. Although the paper may be useful as a guide, the title is misleading since Bitcoin does not guarantee the order of transactions (no […]

Swagger Specification for Coinbase API v2

Coinbase has official client libraries for Python, Ruby, PHP, Node.js and Java, but what about other languages? Enter Swagger. Swagger is an open-source project which includes an specification for describing APIs in JSON or YAML and tools for generating ready-to-go client libraries in several languages. Here at CoinFabrik, we have been writing a first draft […]