Application Binary Interface And Why It Matters To Understand Blockchain Business Models

An Application Binary Interface (ABI) is the interface between two binary program modules that work together. An ABI is a contract between pieces of binary code defining the mechanisms by which functions are invoked and how parameters are passed between the caller and callee. ABIs have become critical in the development of applications leveraging smart contracts, on Blockchain protocols like Ethereum.

Understanding an Application Binary Interface

In understanding an Application Binary Interface, it can be helpful to first define the Application Programming Interface (API). 

Think of an API as a contract between pieces of source code. This contract defines the return value and parameters of a function and dictates whether inheritance is allowed. An API is enforced by a compiler, or a program converting instructions into a format that can be read and executed by a computer. In other words, the API contains instructions on what the source code can and cannot do as part of a platform operating system.

An ABI, on the other hand, is a contract between pieces of binary code. An Application Binary Interface defines the mechanisms by which functions are invoked and how parameters are passed between the caller and callee. The ABI also governs how programs are loaded into memory and how libraries are implemented. Indeed, the ABI is enforced by the linker – defined as a program used with a compiler to provide links to libraries needed for an executable program.

This means the ABI contains rules on how unrelated code must work together and how processes should coexist on the same system. While the API lists the functions that may be called, the ABI dictates how each function may be called. ABIs are commonly established between user programs and libraries but also in OS services and programming languages.

Application Binary Interface functions

ABIs cover a variety of functions, including:

  • Processor instruction sets that denote details such as memory access types and register file structure.
  • How an application makes system calls to the OS and whether direct systems calls or procedure calls are used to system call stubs.
  • Basic data type layout, size, and alignment. 

Calling convention, which dictates how arguments of functions are passed and return values retrieved. Calling convention controls which parameters are passed on the stack and which are passed in registers. It also assigns registers to function parameters and determines whether the first function parameter passed on the stack is pushed first or last.

Complete and embedded ABIs

Complete ABIs

A complete ABI enables a program from the OS supporting it to run without modifications on any similar system. This is on the proviso that shared libraries exist and similar prerequisites are satisfied.

For example, the Intel Binary Compatibility Standard (iBCS) is the standardized ABI for Unix operating systems on Intel-compatible computers. 

Embedded ABIs

Embedded ABIs (EABIs) specify conventions for register usage, data types, stack frame organization, and file formats for use in an embedded operating system.

Object code created by compilers to support the EABI is compatible with the code generated by other compilers. This enables developers to link the library generated with one compiler with the library generated by another using object code.

Ultimately, embedded ABIs are designed for performance optimization. Operating within the limits of an embedded system, the ABI removes the majority of abstractions made between kernel and user code in complex operating systems.

PowerPC – created in an alliance between Apple, IBM, and Motorola – is an example of a widely used EABI.

Key takeaways:

An Application Binary Interface is the interface between two binary program module programs allowing them to work together.

While an Application Programming Interface (API) is a contract between two pieces of source code, an ABI is a contract between two sources of binary code. The ABI also dictates how functions may be called from the API.

Application Binary Interfaces are present in several scenarios. They influence processor instruction sets and determine how an application makes system calls to the OS. An ABI also dictates the layout, size, and alignment of basic data types.

Related Blockchain Business Frameworks


Web3 describes a version of the internet where data will be interconnected in a decentralized way. Web3 is an umbrella that comprises various fields like semantic web, AR/VR, AI at scale, blockchain technologies, and decentralization. The core idea of Web3 moves along the lines of enabling decentralized ownership on the web.

Blockchain Protocol

A blockchain protocol is a set of underlying rules that define how a blockchain will work. Based on the underlying rules of the protocol it’s possible to build a business ecosystem. Usually, protocol’s rules comprise everything from how tokens can be issued, how value is created, and how interactions happen on top of the protocol.

Hard Fork

In software engineering, a fork consists of a “split” of a project, as developers take the source code to start independently developing on it. Software protocols (the set of rules underlying the software) usually fork as a group decision-making process. All developers have to agree on the new course and direction of the software protocol. A fork can be “soft” when an alteration to the software protocol keeps it backward compatible or “hard” where a divergence of the new chain is permanent. Forks are critical to the development and evolution of Blockchain protocols.

Merkle Tree

A Merkle tree is a data structure encoding blockchain data more efficiently and securely. The Merkle tree is one of the foundational components of a Blockchain protocol.


The nothing-at-stake problem argues that validators on a blockchain with a financial incentive to mine on each fork are disruptive to consensus. Potentially, this makes the system more vulnerable to attack. This is a key problem that makes possible underlying blockchain protocols, based on core mechanisms like a proof-of-stake consensus, a key consensus system, that together the proof-of-work make up key protocols like Bitcoin and Ethereum.

51% Attack

A 51% Attack is an attack on the blockchain network by an entity or organization. The primary goal of such an attack is the exclusion or modification of blockchain transactions. A 51% attack is carried out by a miner or group of miners endeavoring to control more than half of a network’s mining power, hash rate, or computing power. For this reason, it is sometimes called a majority attack. This can corrupt a blockchain protocol that malicious attackers would take over.

Proof of Work

A Proof of Work is a form of consensus algorithm used to achieve agreement across a distributed network. In a Proof of Work, miners compete to complete transactions on the network, by commuting hard mathematical problems (i.e. hashes functions) and as a result they get rewarded in coins.

Application Binary Interface

An Application Binary Interface (ABI) is the interface between two binary program modules that work together. An ABI is a contract between pieces of binary code defining the mechanisms by which functions are invoked and how parameters are passed between the caller and callee. ABIs have become critical in the development of applications leveraging smart contracts, on Blockchain protocols like Ethereum.

Proof of Stake

A Proof of Stake (PoS) is a form of consensus algorithm used to achieve agreement across a distributed network. As such it is, together with Proof of Work, among the key consensus algorithms for Blockchain protocols (like the Ethereum’s Casper protocol). Proof of Stake has the advantage of security, reduced risk of centralization, and energy efficiency.

Proof of Work vs. Proof of Stake


Proof of Activity

Proof-of-Activity (PoA) is a blockchain consensus algorithm that facilitates genuine transactions and consensus amongst miners. That is a consensus algorithm combining proof-of-work and proof-of-stake. This consensus algorithm is designed to prevent attacks on the underlying Blockchain.

Blockchain Economics

According to Joel Monegro, a former analyst at USV (a venture capital firm) the blockchain implies value creation in its protocols. Where the web has allowed the value to be captured at the applications layer (take Facebook, Twitter, Google, and many others). In a Blockchain Economy, this value might be captured by the protocols at the base of the blockchain (for instance Bitcoin and Ethereum).

Blockchain Business Model Framework

A Blockchain Business Model is made of four main components: Value Model (Core Philosophy, Core Value and Value Propositions for the key stakeholders), Blockchain Model (Protocol Rules, Network Shape and Applications Layer/Ecosystem), Distribution Model (the key channels amplifying the protocol and its communities), and the Economic Model (the dynamics through which protocol players make money). Those elements coming together can serve as the basis to build and analyze a solid Blockchain Business Model.


Blockchain companies use sharding to partition databases and increase scalability, allowing them to process more transactions per second. Sharding is a key mechanism underneath the Ethereum Blockchain and one of its critical components. Indeed, sharding enables Blockchain protocols to overcome the Scalability Trilemma (as a Blockchain grows, it stays scalable, secure, and decentralized).


A decentralized autonomous organization (DAO) operates autonomously on blockchain protocol under rules governed by smart contracts. DAO is among the most important innovations that Blockchain has brought to the business world, which can create “super entities” or large entities that do not have a central authority but are instead managed in a decentralized manner.

Smart Contracts

Smart contracts are protocols designed to facilitate, verify, or enforce digital contracts without the need for a credible third party. These contracts work on an “if/when-then” principle and have some similarities to modern escrow services but without a third party involved in guaranteeing the transaction. Instead, it uses blockchain technology to verify the information and increase trust between the transaction participants.

Non-Fungible Tokens

Non-fungible tokens (NFTs) are cryptographic tokens that represent something unique. Non-fungible assets are those that are not mutually interchangeable. Non-fungible tokens contain identifying information that makes them unique. Unlike Bitcoin – which has a supply of 21 million identical coins – they cannot be exchanged like for like.

Decentralized Finance

Decentralized finance (DeFi) refers to an ecosystem of financial products that do not rely on traditional financial intermediaries such as banks and exchanges. Central to the success of decentralized finance is smart contracts, which are deployed on Ethereum (contracts that two parties can deploy without an intermediary). DeFi also gave rise to dApps (decentralized apps), giving developers the ability to build applications on top of the Ethereum blockchain.

History of Bitcoin

The history of Bitcoin starts before the 2008 White Paper by Satoshi Nakamoto. In 1989 first and 1991, David Chaum created DigiCash, and various cryptographers tried to solve the “double spending” problem. By 1998 Nick Szabo began working on a decentralized digital currency called “bit gold.” By 2008 the Bitcoin White Paper got published. And from there, by 2014, the Blockchain 2.0 (beyond the money use case) sprouted out.


An altcoin is a general term describing any cryptocurrency other than Bitcoin. Indeed, as Bitcoin started to evolve since its inception, back in 2009, many other cryptocurrencies sprouted due to philosophical differences with the Bitcoin protocol but also to cover wider use cases that the Bitcoin protocol could enable.


Ethereum was launched in 2015 with its cryptocurrency, Ether, as an open-source, blockchain-based, decentralized platform software. Smart contracts are enabled, and Distributed Applications (dApps) get built without downtime or third-party disturbance. It also helps developers build and publish applications as it is also a programming language running on a blockchain.

Ethereum Flywheel

An imaginary flywheel of the development of a crypto ecosystem, and more, in particular, the Ethereum ecosystem. As developers join in and the community strengthens, more use cases are built, which attract more and more users. As users grow exponentially, businesses become interested in the underlying ecosystem, thus investing more in it. These resources are invested back in the protocol to make it more scalable, thus reducing gas fees for developers and users, facilitating the adoption of the whole business platform.


Solana is a blockchain network with a focus on high performance and rapid transactions. To boost speed, it employs a one-of-a-kind approach to transaction sequencing. Users can use SOL, the network’s native cryptocurrency, to cover transaction costs and engage with smart contracts.


In essence, Polkadot is a cryptocurrency project created as an effort to transform and power a decentralized internet, Web 3.0, in the future. Polkadot is a decentralized platform, which makes it interoperable with other blockchains.


Launched in October 2020, Filecoin protocol is based on a “useful work” consensus, where the miners are rewarded as they perform useful work for the network (provide storage and retrieve data). Filecoin (⨎) is an open-source, public cryptocurrency and digital payment system. Built on the InterPlanetary File System.


BAT or Basic Attention Token is a utility token aiming to provide privacy-based web tools for advertisers and users to monetize attention on the web in a decentralized way via Blockchain-based technologies. Therefore, the BAT ecosystem moves around a browser (Brave), a privacy-based search engine (Brave Search), and a utility token (BAT). Users can opt-in to advertising, thus making money based on their attention to ads as they browse the web.

Decentralized Exchange

Uniswap is a renowned decentralized crypto exchange created in 2018 and based on the Ethereum blockchain, to provide liquidity to the system. As a cryptocurrency exchange technology that operates on a decentralized basis. The Uniswap protocol inherited its namesake from the business that created it — Uniswap. Through smart contracts, the Uniswap protocol automates transactions between cryptocurrency tokens on the Ethereum blockchain.

Read Next: Proof-of-stakeProof-of-workBitcoinEthereumBlockchain.

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