# Four eras of blockchain computing ###### tags: `Reading` :::info [4 Eras of Blockchain Computing: Degrees of Composability](https://a16z.com/2018/12/16/4-eras-of-blockchain-computing-degrees-of-composability/) by [Jesse Walden](https://a16z.com/author/jesse-walden/) December 16, 2018 Andreessen Horowitz ::: Very inspired by an article from @a16z by @Jesse Walden about the role of composability in crypto networks. Though not new, especially with regard to the velocity of innovation in this ecosystem, nevertheless as important today as before. "A platform is composable if its existing resources can be used as building blocks and programmed into higher order applications. Composability is important because it allows developers to do more with less, which in turn, can lead to more rapid and compounding innovation." According to this article, composability allows to sketch out a model of blockchain computing evolution eras, such that the various crypto networks, architectures and infrastructures can be categorized into four distinct eras: Calculator Era – application specific, limited composability Mainframe Era – turing complete, high composability Server Era – application specific, punt on composability Cloud Era – turing-complete, scalable composability Our challenge is to engineer communication interfaces that will allow trustless composability, which in turn will drive the #networkeffects towards greater collaboration and creativity.