REST API Gateway

Simplify Blockchain Development With Powerful APIs

Enterprise-grade blockchain APIs to deploy and manage Smart Contracts, send Ethereum transactions, query blockchain data, and more.

What it

REST API Gateway


What it is

A Full Suite of APIs to Make Blockchain Development Easy for Any Developer

The REST API Gateway gives application developers everything they need to focus on their app's business logic and user experience, without getting stuck in the complexities of Ethereum transaction submission, thick Web3 client libraries, nonce management, RLP encoding, transaction signing, and smart contract management.

Just use the intuitive REST APIs generated for you, along with industry standard OpenAPI (Swagger) definitions and management APIs.

Let the REST API Gateway take care of the rest, backed by a fully-managed high throughput Apache Kafka infrastructure.  Keep track of your deployed smart contracts, with descriptive names and API documentation, rather than strings of Hex addresses.

Deploy Your First Smart Contract in Seconds

All of the complexities of submitting transactions to Ethereum are handled for you. With one click in the UI you can deploy your first smart contract, then explore that API to send transactions, and read data in a convenient web experience. No special blockchain coding expertise required.

REST APIs for Your On-Chain Logic & Data

OpenAPI (Swagger) definitions are generated for the Solidity Smart Contracts you enable on the REST API Gateway. The Blockchain becomes as simple to code against as any modern web based system. No thick client libraries needed in your app, no complex type mapping. Connect directly from your core applications, or use your existing Integration tier / Enterprise Service Bus (ESB).

Reliable Transaction Streaming, over Apache Kafka

The REST API Gateway handles smart contract compilation, nonce management, RLP encoding and more. It's all backed by the industry standard for reliable ordered streaming of transactions - Apache Kafka. So the same convenient APIs take you from first use, through to enterprise grade production use cases at scale.


Are You a ConsenSys Quorum Blockchain User?

Kaleido is the preferred migration partner working with ConsenSys to ensure continuation of the Quorum Blockchain service. If you’re interested in continuing your service by migrating to Kaleido, please contact our team and we'll be happy to assist.
How it works

What Makes Polygon ID Different on Kaleido

Kaleido makes it easy to build applications that go beyond a simple login to create an identity layer that gives people more control and portability of their data.

Kaleido offers identity as a service with hosting of both claim and verifier servers. Our platform then brings identity solutions to life with pre-built, pluggable services like wallets, tokens, and public and private connectivity. Meet the demands of the most complex use cases with fully customizable identity apps.

Pluggable Tools

Match identity as a service with web3 building blocks to make complete solutions


Build on an ISO 27k and SOC 2 certified platform with built-in HA/DR, 24/7 support, & SLAs

Custom Configurations

Connect directly to public chains or build on custom, permissioned environments

User Friendly

Couple zk-backed security with simple-to-use interfaces for business teams and end users

Flexible Deployments

Deploys on popular cloud properties, hybrid options, and geographic regions

Polygon Approved

Get support from Polygon approved implementation experts to architect next gen identity solutions

Hyperledger Fabric at a glance


Built for permissioned networks


Data isolation and strict governance enabled by Hyperledger Fabric certificate authority

Transaction Flow

Unique Execute-Order-Commit endorsement model where transactions are initially executed on a set of peers while ordering service handles packaging and delivery

Consensus Algorithms

Ordering can be switched based on the needs of the environment with pluggable consensus algorithms

Smart Contract Language

Go, Java, Node.js

What Is Hyperledger Fabric?

Since launching in 2015, Hyperledger Fabric has been a top choice for enterprises looking to build apps on permissioned blockchain networks. The modular architecture is capable of powering large-scale applications that require enterprise-grade data security.

The ability to protect certain details of peer transactions has made Hyperledger Fabric a go-to protocol for industries like financial services, supply chains, and the insurance industry. It works for complex use cases that involve personally identifiable information and proprietary business data.

Hyperledger Fabric is one of the many protocol choices available on Kaleido. With a full suite of plug and play services, flexible cloud deployment options, and powerful APIs, Kaleido is the easiest way to run a Fabric network anywhere.

Benefits of Hyperledger Fabric

Hyperledger Fabric is an open source project designed to handle enterprise-grade use cases. Key differentiators are its quick transaction throughput and its modularity, allowing for more innovation and optimization regardless of industry use cases. Other benefits include scalability and security, key pillars of any enterprise application.

Modular & Pluggable

Hyperledger Fabric is a modular blockchain framework that allows you to plug in different components, such as consensus algorithms and membership services, and tailor networks to your needs

Open source

Part of the Hyperledger project of the Linux Foundation, Hyperledger Fabric is an open source protocol that allows the enterprise to build custom applications and limit vendor risks


With a high level of security for enterprise users, Fabric uses a permissioned network to prevent unauthorized access

Hyperledger Fabric certified service provider badge

Our Hyperledger Fabric Expertise

Kaleido is a Hyperledger Certified Service Provider (HCSP) with a deep expertise in helping enterprises successfully adopt Hyperledger tools. Our founding partners are also active with the Hyperledger Foundation. Sophia Lopez is a General Member representative on the Hyperledger Foundation Governing Board and Jim Zhang is a member of the Hyperledger Foundation Technical Oversight Committee.

Talk to an Expert

Benefits of Quorum

Quorum is a blockchain protocol specially designed for use in a private blockchain network, where there is only a single member owning all the nodes or a consortium blockchain network where multiple members each own a portion of the network.


Quorum is designed to be highly scalable, with low transaction latencies and the ability to support a higher number of transactions per second than other blockchain protocols. This makes it well-suited for use in high-volume applications.


Quorum includes a number of security features that are designed to protect sensitive or proprietary data, like private transactions that allow network participants to transact without revealing the details of their transactions to the rest of the network.


Quorum is based on the Ethereum protocol and can support a wide range of decentralized applications and smart contracts. It is also highly modular and customizable so that it can be tailored to the needs of specific use cases.

Gas-free transactions

There is no cost required to submit transactions to a Quorum network, unlike Ethereum, which requires the payment of high and unpredictable gas fees to submit transactions.

Hyperledger Fabric certified service provider badge

Our Hyperledger Fabric Expertise

Kaleido is a Hyperledger Certified Service Provider (HCSP) with a deep expertise in helping enterprises successfully adopt Hyperledger tools. Our founding partners are also active with the Hyperledger Foundation. Sophia Lopez is a General Member representative on the Hyperledger Foundation Governing Board and Jim Zhang is a member of the Hyperledger Foundation Technical Oversight Committee.

Talk to an Expert
How it works

How it Works

Blockchain Development, Simplified

Kaleido provides the enterprise grade connectivity your applications and back-office systems need for high throughput reliable connectivity to your on-chain smart contracts. You can submit transactions to your nodes with ease, query the data on your chain, and listen to events. We generate modern REST APIs with full OpenAPI (Swagger) documentation from your Solidity source code, with all of the methods, events and types processed – even the developer docs loaded into the definition. 

For simple first use you can then perform transactions synchronously against the chain, waiting for them to complete. Then as you move towards production, use our throttling and nonce management over our Kafka backbone to stream transactions into the chain. Of course all of this is in addition to having direct JSON/RPC access to your nodes, for development of smart contract logic using Truffle, or DevOps activities with a Geth console.

Deploy and manage your Smart Contracts via our blockchain API and user interface. You upload your .sol or .zip file containing your Solidity package, and we generate you a REST API that can interact with any on-chain contract with the same Application Binary Interface (ABI). 

For example, if you upload an ERC20 contract you get an interface that can query common data and submit transactions to any ERC20 based contract. You can use this generated gateway REST API to deploy new contract instances, which you know are using the same Solidity package and compiler version. e.g. each contract instance is identical. The UI and REST API of the gateway lets you manage these instances.

Enterprise Use Cases
Run Better on Kaleido

Hyperledger Fabric is a private blockchain that allows developers to create subnets, or channels, meaning that certain proprietary or personal information can remain confidential. This makes Fabric a protocol of choice for industries like financial services, insurance, and supply chain management.

Supply Chains

Hyperledger Fabric networks can increase transparency and traceability of transactions within the network. This transparency can be used to monitor real-time location data, limit fraud and counterfeit goods, and track ESG efforts.

Digital Assets

Complex multi-party business networks built on Fabric can easily tokenize assets, transact instantly, share data, and eliminate cumbersome paperwork as financial business flows are automated.


Moving insurance transactions to blockchain can eliminate fraud, automate claim processing, and digitize legacy systems. Hyperledger Fabric also allows stakeholders to automate Know Your Customer (KYC) processes via smart contracts.
Why Kaleido

Everything You Need to Build Enterprise-Grade Blockchain Networks & Digital Assets

Try Truffle on Kaleido

Kaleido's blockchain platform makes it radically simple for businesses to create complete web3 networks and applications. With just a few clicks, you can launch a blockchain network, deploy it globally, set up governance, and start plugging in familiar services.

Quickly Launch Blockchain

Launch blockchain networks in minutes
Choose from leading protocols including Ethereum, Polygon Edge, Hyperledger Fabric and more
Select permissioned chains, appchains,  sidechains, or consortium chains
Deploy on AWS, Azure or on-prem
Stand up nodes worldwide in regions of your choice

Simplify Development to Get to
Production Fast

Access 40+ plug-and-play services for wallets, key management, storage, data, and more
Automate management and deployment with our fully API-enabled platform
Turn any smart contract into familiar APIs with our smart contract API generator
Make digital assets, NFTs, and consortia easy with our dedicated solutions
Mint, manage, and burn tokens at scale with robust tooling

All Backed by Enterprise-Grade Infrastructure and Support

Modern cloud scale architecture
Built-in high availability and disaster recovery
ISO 27k and SOC 2 Type 2 compliant
Integrate seamlessly with existing internal systems
Open source tech and no vendor lockin
24x7 support and SLAs

Use Cases

Picture of a Bank in Hexagons

Decentralized finance

Make AML & KYC instant and automated with verified identities
A Person Gaming in Hexagons

Digital onboarding

Verify the identity of users remotely and securely with immutable IDs

Healthcare applications

Transfer data, verify IDs, and reduce administrative costs with pluggable DID solutions

Self-sovereign ID

Allow people to fully own and control access to their data with immutable identity

Voting and elections

Eliminate fraud with secure and transparent voting processes that are free manipulation

Loyalty and rewards

Simplify reward and loyalty programs with automated and verified connections to customers

Enterprise Use Cases Run Better on Kaleido

Quorum is a protocol of choice for industries like financial services, insurance, and supply chain management where enterprise-grade.

Additional Resources
Learn More About
REST API Gateway
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REST API Gateway

Common Questions about Blockchain REST APIs

What is a REST API?

A REST API (Representational State Transfer API) is a type of API (Application Programming Interface) that allows communication between different systems or applications over the internet. REST APIs use HTTP (Hypertext Transfer Protocol) methods to send and receive data, and are designed to be lightweight, easy to use, and flexible.

REST APIs typically use HTTP methods such as GET, POST, PUT, DELETE, and PATCH to perform different actions. For example, the GET method is used to retrieve data from a server, while the POST method is used to send data to a server for processing.

REST APIs use a standard set of HTTP status codes to indicate the success or failure of a request. For example, a status code of 200 indicates that the request was successful, while a status code of 404 indicates that the requested resource could not be found.

REST APIs are often used to expose the data and functionality of web-based systems and services to developers, allowing them to build applications that interact with those systems and services.

How are REST APIs used in blockchain development?

REST APIs can be used in blockchain development to allow applications and services to interact with a blockchain and access its data and functionality.

For example, a blockchain-based application might use a REST API to:

  1. Query the blockchain for information about specific transactions, blocks, or addresses.
  2. Submit transactions to the blockchain for processing and inclusion in a block.
  3. Monitor the blockchain for new transactions or blocks and receive notifications when they occur.
  4. Interact with smart contracts deployed on the blockchain.

By using a REST API, developers can build applications that can read data from and write data to a blockchain, as well as interact with smart contracts and other features of the blockchain.

Some blockchain platforms, such as Ethereum, provide their own built-in REST APIs that developers can use to interact with the blockchain. Other platforms, such as Bitcoin, do not have built-in REST APIs, but developers can use third-party tools or services to create their own APIs that allow access to the blockchain's data and functionality.

Overall, REST APIs are an important tool for developers building applications on top of a blockchain, as they provide a convenient and easy-to-use interface for accessing and interacting with the blockchain.

What are the benefits of using REST APIs for blockchain development?

There are several benefits to using REST APIs in blockchain development:

  1. Flexibility: REST APIs are flexible and can be used to access a wide range of data and functionality on a blockchain. This makes them suitable for use in a variety of different blockchain-based applications and services.
  2. Ease of use: REST APIs use simple HTTP methods and follow standard conventions, making them easy for developers to use and understand.
  3. Platform independence: REST APIs use standard HTTP protocols, which makes them platform-independent. This means that applications and services built using REST APIs can be used on any device or platform that has an internet connection and an HTTP client.
  4. Scalability: REST APIs are designed to be scalable, allowing them to handle large volumes of requests without experiencing performance issues.
  5. Interoperability: REST APIs allow different applications and services to communicate and exchange data with each other, regardless of their underlying technologies. This promotes interoperability and makes it easier for developers to build applications that can interact with a wide range of systems and services.

Overall, the use of REST APIs in blockchain development can help developers build flexible, scalable, and interoperable applications that can interact with a blockchain and access its data and functionality.

Who should use blockchain REST APIs?

REST APIs can be used by a wide range of individuals and organizations that are interested in building applications or services on top of a blockchain. Some examples of groups that might use blockchain REST APIs include:

  1. Supply chain management companies: Companies that manage supply chain systems can use REST APIs to track goods as they move through the supply chain and to verify the authenticity of products using the blockchain.
  2. Financial institutions: Financial institutions can use REST APIs to access data from a blockchain and perform functions such as verifying the ownership of assets or tracking the movement of funds.
  3. Healthcare organizations: Healthcare organizations can use REST APIs to securely manage medical records with blockchain, allowing for more efficient and secure sharing of patient data.
  4. Government agencies: Government agencies can use REST APIs to access data on a blockchain and perform functions such as verifying the authenticity of documents or tracking the movement of assets.

Overall, any organization or individual that is interested in building applications or services on top of a blockchain can benefit from using REST APIs.