Frequently asked questions

Chainlink is the industry standard for building, accessing, and selling oracle services needed to power hybrid smart contracts on any blockchain. Chainlink oracle networks provide smart contracts with a way to reliably connect to any external API and leverage secure offchain computations for enabling feature-rich applications. Chainlink currently secures tens of billions of dollars across DeFi, insurance, gaming, and other major industries, and offers global enterprises and leading data providers a universal gateway to all blockchains.

A blockchain oracle is any system that services a smart contract by providing it with data from an offchain source or connecting it with an offchain system. Oracles enable connectivity between blockchains and real-world data by interfacing with external APIs and data feeds, allowing them to pull data for or push data from a smart contract.

Oracles enable smart contracts to interact with offchain resources. Without oracles, smart contracts can only access data within a blockchain, severely limiting their potential applications. The majority of industry-changing real-world use cases for smart contracts require offchain data and computation for proper execution and often an integration with existing payment rails to settle a contract. For example, a smart contract may require high-quality weather data from a reputable source like AccuWeather to trigger a transaction. It may also require the ability to pay out escrowed fiat currency through existing financial infrastructure, such as a bank checking account.

Real-world data, also known as offchain data or external data, refers to the current global data infrastructure that exists outside of the blockchain that must be brought onchain via oracles to be used by smart contract applications. Like a computer without the Internet, blockchain-based smart contracts have inherent value on their own, such as creating and swapping tokens. However, they become exponentially more powerful when externally connected to the vast and accelerating data and API economy taking root outside the blockchain ecosystem.

The oracle problem, also known as the “smart contract connectivity problem”, refers to a blockchain’s inability to natively pull data from or push data to any external offchain system due to the strong security properties created by a blockchain’s consensus mechanism. 

Blockchain nodes are designed to perform standardized and uniform operations to generate consensus on a set of transactions (solving the double-spend problem). However, they are not suited to answer subjective questions about probabilistic real-world data, as blockchain nodes do not always have access to the same information, making generating consensus on even the most basic data requests challenging and source quality enforcement impossible. It is for this reason blockchains focus on generating definitive truth about the validity of transactions, but limit connections to any offchain systems to ensure the network always remains live and produces deterministic results for incoming transactions. 

In order to create a bridge between the blockchain (onchain) and the outside world (offchain), an additional and separate piece of infrastructure known as an “oracle” is required. However, the use of a centralized oracle can result in manipulated data inputs and outputs, meaning the oracle mechanism itself needs to be highly decentralized to ensure the security of a smart contract’s execution is maintained end-to-end.

The Chainlink Network refers to all of the decentralized oracle networks actively operating using the Chainlink protocol, including individual oracles, data providers running their own node, and node operators. By enabling smart contracts to quickly and securely connect to offchain data sources using decentralized oracle networks, the Chainlink Network helps developers build more robust and diverse blockchain applications using real-world inputs and outputs. Additionally, as middleware between low-level blockchain protocols and external, offchain data sources, the Chainlink Network serves as an abstraction layer for data providers to easily sell their existing APIs to any blockchain network.

A decentralized oracle network consists of multiple blockchain oracles run by independent node operators that are chosen to retrieve and validate data from several different offchain sources. Each of the oracles’ responses within a decentralized oracle network are aggregated together to form a single trusted data point, which can be used to trigger smart contracts on any blockchain and really any system that needs highly reliable data that’s provably accurate. The data delivered onchain can be hosted in a Reference Contract (pull model), and/or delivered directly to consuming smart contracts (push model). 

The Chainlink Network is made up of multiple decentralized oracle networks running simultaneously and independently of one another. For example, if a smart contract requires data about the price of ETH/USD, instead of relying on one individual blockchain oracle to pull price data from one API source, the smart contract can use a decentralized oracle network to have multiple oracle nodes pull data from several different API sources and then aggregate the result. 

Through decentralized computation, Chainlink-powered decentralized oracle networks provide users superior security and reliability guarantees on the inputs and outputs of their smart contract, ensuring that both onchain and offchain components of a decentralized application are tamper-proof end-to-end.

Node operators are the entities that maintain and run the blockchain oracles that make up each Chainlink oracle network providing smart contracts on various blockchains access to external data and resources. These operators consist of professional validators for various blockchain networks, teams of highly experienced DevOps engineers, and leading organizations such as Accuweather, the Associated Press, and Deutsche Telekom MMS that focus specifically on building infrastructure for the Chainlink ecosystem. Additionally, external data vendors and API providers can monetize their data sets by running a Chainlink Node and providing signed data directly to smart contracts. Node operators are able to configure their blockchain oracle node to connect to any offchain data source and onchain blockchain environment, providing a high degree of flexibility. 

Node operators within the Chainlink Network strictly adhere to the best security practices and use external monitoring systems to ensure a secure and reliable operation is maintained around the clock. Third-party marketplaces like market.link provide users insight into the current and historical performance of each individual node operator. Additionally, anybody can become a Chainlink node operator and immediately begin providing smart contracts access to offchain data. If you are interested in running a node, please navigate to our documentation.

Transaction Value Enabled (TVE) is a cumulative flow metric that measures the aggregate monetary value of transactions facilitated by a protocol over a given time period. Chainlink TVE is measured as the total US dollar volume of transactions enabled by Chainlink oracles. This includes every transaction where:

• A Chainlink Price Feed reference contract was called on Arbitrum, Avalanche, BSC, Base, Celo, Ethereum, Fantom, Linea, Metis, Moonbeam, Moonriver, Optimism, Polygon, Polygon ZKEVM, Scroll, Solana, and Gnosis (xDai). 
• A Chainlink Data Stream oracle report was pushed onchain on Arbitrum, Avalanche, Base, and Optimism.  
• Chainlink CCIP was used to transfer value cross-chain on Arbitrum, Astar, Avalanche, Base, Binance, Blast, Celo, Ethereum, Gnosis, Kroma, Linea, Mantle, Metis, Mode, Optimism, Polygon, Polygon zkEVM, Scroll, WEMIX3.0, X Layer, Zircuit, and zkSync Era.

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TVE is calculated across millions of transactions using onchain data and resolved across thousands of token prices. TVE measures both volume and facilitated flow, capturing not only input and output values but also how a protocol is used within transactions to facilitate value securely. Chainlink TVE encompasses a wide variety of transactions and movements within transactions that require Chainlink oracles for accurate price updates or cross-chain interoperability, including trading, lending, rebalancing, automated yield farming, stablecoin minting, perpetuals, and many more DeFi use cases.

Chainlink provides users with a simple to integrate and pre-built decentralized oracle solution that can be utilized today by any smart contract on any blockchain. A Chainlink integration allows developers to focus on their application’s core business logic without needing to allocate precious resources to rebuilding infrastructure. Rolling your own oracle is extremely difficult and probabilistic as the oracle problem is complicated, technical, nuanced, and requires constant monitoring, upkeep, funding, and resources to maintain properly.

The ability to easily integrate a project with Chainlink’s decentralized oracle network has enabled numerous teams to avoid the hassle of building their own oracle, allowing them to instead focus on innovating and building use cases. Additionally, as Chainlink users collectively fund oracle networks as a public good, the costs of using Chainlink are far lower than attempting to build and manage your own solution. For example, a growing list of DeFi applications now use and collectively fund Chainlink Price Feeds. If you are interested in integrating with Chainlink, please reach out.

The Chainlink ecosystem includes hundreds of dApps, blockchains, node operators, and data providers, as well as an expansive research and open-source development community. The Chainlink Network powers the leading DeFi applications including Aave, Synthetix, and Compound, securing billions of dollars in user funds. As Chainlink is a permissionless framework for building oracles, anybody can join the network at any time and immediately start contributing to the growing ecosystem. See the Chainlink Data Feeds page for a more in-depth list of users, sponsors, and node operators.

Chainlink’s economic model revolves around the use of the LINK token to pay for the operation of a wide variety of oracle services in demand by smart contract developers and Web2 systems, as well as around using LINK as a cryptoeconomic mechanism for incentivizing the correct performance of oracle services and providing user assurances. 

The supply side of Chainlink economics involves launching new oracle services and continually optimizing existing ones to further the adoption of Chainlinked smart contracts and trust-minimized Web2 systems with the aim of capturing new fee opportunities. It also includes continually provisioning higher security guarantees on oracle services through staking and other security assurances to enable more advanced and higher-value smart contracts to exist.

On the demand side, users pay node operators in LINK to access oracle services. Node operators and community members will also be able to stake LINK in the future as a form of service-level guarantee around oracle node performance, providing a powerful incentive and penalty mechanism for Chainlink nodes to generate accurate and timely oracle reports. Continued Chainlink adoption incentivizes oracle nodes to compete for growing user fees from Chainlinked dApps. This competition encourages oracle nodes to strengthen their reputation and increase their LINK stake, showcasing their commitment to honest behavior and maximizing the cost of attack for malicious actors. Increased stake can also drive increased opportunities for nodes to earn user fees from Chainlinked dApps since they are viewed as having greater incentive to perform jobs in a timely and accurate manner.

Within Chainlink’s economic model, the increased availability and adoption of oracle services cultivates more fee opportunities for node operators who support the protocol. This creates a virtuous cycle in which oracle networks can sustain themselves on user fees alone by providing new trust-minimized services, increasing security guarantees, and capturing new fee opportunities from growing adoption.

For more information on Chainlink economics, see the following resources:

• Chainlink Staking: Long-Term Goals, Roadmap, and Initial Implementation
• Chainlink Economics 2.0 and the Market for Trust-Minimized Apps | Sergey Nazarov
• The Security Impact Curve and Future Fee Opportunity in Chainlink Oracle Networks
• The Chainlink 2.0 Whitepaper

The Chainlink Network is composed of the highest quality Sybil-resistant oracle nodes, operated by leading DevOps and security teams, such as Deutsche Telekom MMS, who have decades of experience running mission-critical infrastructure. The security-reviewed and tamper-resistant nodes that comprise Chainlink oracle networks are highly transparent: Their performance metadata is made publicly available to users and can be found onchain or on third-party sites such as market.link.

Chainlink also employs a defense-in-depth approach where multiple security solutions are used in combination to increase oracle network robustness and reliability. This includes the security design principles underpinning the Cross-Chain Interoperability Protocol (CCIP), cryptoeconomic security through Staking, and much more.

The Chainlink Network consists of hundreds of professionally-operated and community-run nodes, allowing for the creation of numerous Sybil-resistant and tamper-proof oracle networks that can scale up in decentralization as the value being secured rises. Chainlink nodes are operated by professional DevOps and security teams with decades of experience operating mission-critical infrastructure and are already securing tens of billions of dollars of value across multiple blockchain networks. The performance data about each Chainlink node can be found onchain or on independent sites such as market.link.

Chainlink is not a singular monolithic network but rather a collection of more than 1,000 decentralized oracle networks, each configured to meet the specific requirements of its distinct set of users.

While oracle networks share many common characteristics with blockchains—namely decentralization and cryptoeconomic incentives—there are key differences in their operation. Blockchains operate in a highly deterministic and predictable environment, focused on validating transactions using cryptography (private keys and hash functions), as well as historical state (previously validated transactions stored on the ledger). Oracle networks, on the other hand, operate in highly non-deterministic and unpredictable environments where consensus is generated about external events in the real world.

Oracle networks are not static but rather require regular updates and adjustments to maintain a high level of security and reliability. The ability for adjustments to be made in response to unpredictable externalities is how Chainlink has securely scaled to over 1,000 independent oracle networks and can continue scaling to help secure onchain markets that potentially involve trillions of dollars worth of tokenized assets.

In order to meet user demand and continuously improve performance, Chainlink services are updated from time to time to introduce new features and functionalities. Additionally, due to the dynamic nature of offchain environments, swift updates may also be required in response to various externalities. Examples may include, but are not limited to, token migrations, protocol rebrands, extreme market events, and upstream issues with data or node operations.

In alignment with software development best practices, updates can encompass offchain and/or onchain processes as Chainlink services are composed of both onchain smart contract logic and offchain infrastructure such as the Chainlink node client and data provider end-points.

Offchain updates commonly take place at the node operator level, where each individual operator manages their own Chainlink node configuration. Updates can include upgrading to a new Chainlink node software version to improve performance or changing API endpoints in a job specification if a data provider becomes unreliable. Offchain updates can also take place at the data provider level, such as responding to a token migration event or other externalities.

Onchain updates take place at the smart contract level, where a multi-signature safe (multisig) is used to modify onchain parameters relating to a Chainlink service. This can include replacing faulty nodes on a specific oracle network, introducing new features such as Offchain Reporting, or resolving a smart contract logic error. The multisig-coordinated upgradability of Chainlink services involves time-tested processes that balance collusion-resistance with the flexibility required to implement improvements and adjust parameters.

Specifically, the use of a multisig to modify the onchain parameters of Chainlink services allows for a safe, secure, and rapid response to black swan events and other potential incidents on the order of minutes, minimizing service interruption for users. Alternative methods to incident response that don’t utilize a multisig can introduce severe risk to users. For instance, oracle services with immutable onchain logic require a full contract redeployment if any onchain parameter requires modification. This can delay incident response times, introduce significant coordination friction, and necessitate additional actions from users who may not respond in a timely enough manner. 

Signers on Chainlink Gnosis Safe multisigs are selected from multiple high-quality Chainlink node operators with a proven, multi-year track record of securing billions in value within the Chainlink Network, as well as from Chainlink Labs. Signers are also spread across multiple different geographic locations globally and may be rotated on a periodic basis to help mitigate potential risks, such as geographic concentration, as they arise. 

In alignment with industry practices, the identities of signers in Chainlink Gnosis Safe multisigs are not publicly disclosed. Disclosing the exact identities could put those individual signers at risk, such as exposing them to potential spear phishing attacks and other forms of targeted exploitation or social engineering. This balance between transparency and operational security reflects the security-conscious approach taken to every aspect of the Chainlink Network. 

As the Chainlink ecosystem continues to evolve, so too has the approach taken to the upgradability of different oracle networks. For example, all onchain security-critical configuration changes and upgrades to the Cross-Chain Interoperability Protocol (CCIP) must pass through a Role-based Access Control Timelock (RBACTimelock) smart contract. Any proposal must either (1) be proposed by a dedicated ManyChainMultiSig contract and then be subjected to a review period, during which the node operators securing CCIP are able to veto the proposal; or (2) be proposed by a dedicated ManyChainMultiSig contract and be explicitly approved by a quorum of the node operators securing CCIP, providing an alternative path during time-sensitive circumstances. 

Any onchain update that passes the timelock without a veto becomes executable by anyone, which can be done by running a timelock-worker to process executable upgrades. Additionally, CCIP uses a novel ManyChainMultiSig contract structure, which supports the signing of multiple transactions that target multiple chains with a single set of signatures. This provides a scalable solution to managing various CCIP configurations across a growing number of supported blockchains.

With Chainlink Staking v0.2, all onchain security-critical configuration changes and upgrades must pass through a timelock smart contract, which features a time delay of up to a few weeks, with critical configuration changes taking the longest (longer than the unbonding period for withdrawing staked LINK). This allows the community to review and choose to opt out of such changes before they are implemented onchain. 

Moreover, Chainlink is a generalized and modular protocol that enables oracle networks to be customized to meet the exact requirements of users. This includes the ability of users to set up and launch their own Chainlink oracle networks with custom configurations and upgradability processes. 

Security is the number one priority for the Chainlink ecosystem, a north-star objective we do not compromise on. As new technologies arise and the Chainlink platform expands, we will continue to evaluate and implement the best and most secure processes for managing the upgradability of Chainlink services. Information on the upgradability of Chainlink Data Feeds can be found in the Chainlink Documentation.

Yes. The Chainlink source code can be viewed at https://github.com/smartcontractkit.

High-quality data with premium APIs - The Chainlink Network has credential management capabilities, meaning it can fetch and deliver data to smart contracts from premium, password-protected data sources. While free data APIs are useful, most inputs that trigger transactions related to secure user funds will likely need to come from premium APIs. 

‍Flexibility - The Chainlink Network is a highly flexible and blockchain-agnostic oracle framework utilized by DeFi applications, web services, and traditional enterprises alike. By acting as a universal blockchain abstraction layer, users can leverage Chainlink to transmit any kind of data to and from any blockchain environment as desired. 

‍Highly secure and transparent nodes - Chainlink oracle networks consist of security-reviewed and tamper-resistant nodes, such as Deutsche Telekom MMS. These nodes are highly transparent, and their performance data are publicly available to all users at market.link. 

Decentralized and Sybil-resistant networks - Chainlink is the most decentralized oracle network, consisting of security-reviewed nodes that are backed by professional teams, allowing for the creation of numerous Sybil-resistant and tamper-proof oracle networks that can scale up as the value being secured rises. 

Defense in depth - Chainlink employs a defense in depth approach where multiple security solutions are used in combination to increase oracle network robustness and reliability. This includes privacy-preserving cryptography like DECO, trusted hardware such as Town Crier, cryptoeconomic security through implicit/explicit staking, reputation systems, and much more. This multi-layered approach to security increases Chainlink’s end-to-end reliability.

Adoption and network effects - Chainlink is the most widely used and adopted oracle solution in DeFi, securing billions in value in production for innovative DeFi protocols such as Aave, Synthetix, Compound, and creating a growing network effect attracting more users. Chainlink has undergone numerous security audits and has been time-tested on mainnet. 

‍Solid security foundation and world-class research - Chainlink is supported by a multitude of leading engineers and academics, such as Chainlink Labs Chief Scientist Ari Juels, Chainlink Labs Chief Research Officer Dahlia Malkhi, and Chainlink Labs Chief Product Officer Kemal El Moujahid. The researchers working on the Chainlink protocol are industry experts in blockchain oracles and are responsible for some of the most innovative developments in the space, such as DECO, VRF, Mixicles, Town Crier, and more.

Patenting inventions is a common practice around new technologies and can help protect public goods like Chainlink from frivolous litigation and bad actors who could claim ownership of technology that they did not develop. Notable open-source platforms have used patents as a way to help ensure key technologies remain viable and accessible for the long term.

Chainlink nodes can access any authenticated or premium data source API through the use of modular external adapters. External adapters can be written in any programming language and hosted as a serverless function on any cloud provider or web server. These adapters allow Chainlink nodes to access a wide array of data sources, including authenticated and private APIs that require sensitive password keys, such as enterprise backends and subscription-based sources. Thus, Chainlink nodes have a high degree of flexibility as API credentials can be kept offchain and stored securely, separate from the node itself.  

Chainlink oracle networks operate using multiple layers of data aggregation to ensure there is no single point of failure or any reliance on a single source of truth that could be corrupted. This redundancy is not only required to ensure high-value smart contracts consume highly refined data, but also to ensure Chainlink Price Feeds provide full market coverage that reflects the true market price of assets. With Price Feeds securing tens of billions in user funds, these layers of aggregation secure the DeFi ecosystem.

The first aggregation layer is at the data source level where professional data aggregation firms (e.g. BraveNewCoin, CoinGecko) fetch market data from hundreds of exchanges, taking into account volume and liquidity differences, and generate a single weighted reference price point. The second aggregation layer is at the node operator level where each individual Chainlink oracle node sources price data from multiple data aggregation firms and takes the median, mitigating outliers, API downtime, and ensuring nodes do not rely on any one source. The third aggregation layer is at the oracle network level where the responses from multiple oracle nodes are aggregated by taking the median, ensuring no individual node has control over the resulting data point delivered to contracts. All of this together ensures smart contracts consume only the highest quality data that reflects the true market-wide price.

For more information on secure oracle design, refer to our articles on the importance of data quality for DeFi smart contracts and the three levels of data aggregation in Chainlink Price Feeds. 

The Chainlink Price Feeds page provides real-time visualizations of each decentralized price feed that provides onchain exchange rates for cryptocurrencies, stablecoins, commodities, and indices. Users can explore each individual price feed, which offers transparency around which nodes power each feed, each node’s latest response, how often feed updates occur, the gas price paid by each node, the users sponsoring each feed, and hyperlinks to onchain transactions.

LinkPool’s market.link is a permissionless marketplace that allows node operators to display their historical performance and list what oracle services they offer. Users can use this data to filter and analyze each node’s revenue, gas costs, and response times. Developers can also query the Chainlink Market’s Metrics API to access all of this raw data themselves and build their own analysis framework using real-time data regarding the performance of the Chainlink Network.

Through offchain reporting and threshold signatures, Chainlink oracle networks can scale to thousands of secure nodes within a network. Instead of each node making their own onchain transaction for each update, node responses are aggregated offchain, and only a single transaction needs to be submitted onchain. The security of data is cryptographically maintained throughout the entire process. This allows for the creation of Chainlink oracle networks that are highly decentralized while remaining cost-efficient and secure against manipulation through a defense in depth approach. Additionally, unlike other oracle projects, each Chainlink oracle network is entirely independent of one another and does not affect the scalability or throughput of any other Chainlink Network.

Offchain Reporting (OCR) is the third and latest version of the Chainlink Core software client run by Chainlink nodes, which significantly improves the efficiency of how data is aggregated by Chainlink oracles. OCR reduces operating costs by up to 90% and enables the Chainlink Network to generate a 10x increase in the amount of secure, real-world data available to smart contract applications. 

OCR allows Chainlink nodes to communicate offchain and aggregate data at zero gas costs using a distributed, peer-to-peer network. In OCR’s computation model, each node fetches data from one or multiple data sources, signs it with their unique private key, and broadcasts it to the rest of the oracle network offchain. Once a sufficient number of responses have been generated, a single transaction is transmitted onchain containing every node’s observation. The oracle report and node signatures are then validated onchain by a smart contract, providing the transparency and end-to-end security guarantees that are fundamental to Chainlink oracle networks. 

All Chainlink nodes operating in-production run the OCR and FluxMonitor clients in parallel to achieve multi-client diversity and security through redundancy. For a deeper dive into OCR’s design goals and report generation process, read the OCR protocol paper.

Offchain computation refers to trust-minimized executions that are performed outside of a blockchain environment by Decentralized Oracle Networks (DONs). The Chainlink Network provides a wide range of offchain computations that significantly enhance the capabilities of smart contracts and blockchain networks, including scalable code execution, oracle update transaction batching, random number generation, privacy-preserving contracts, fair transaction ordering, and more. The offchain computations performed by DONs extend Chainlink’s functionality far beyond secure data delivery while meeting the decentralized computation guarantees that are fundamental to blockchain technology.

Hybrid smart contracts are an evolution of smart contract design that was pioneered in the Chainlink 2.0 Whitepaper, in which contracts are securely composed of both onchain and offchain computing resources. Hybrid smart contracts are made possible by Chainlink Decentralized Oracle Networks (DONs), which provide a multiplicity of offchain services to existing and future blockchain networks, enabling feature-rich, privacy-preserving, and scalable smart contract applications.

Chainlink Data Feeds are decentralized oracle networks that provide aggregated financial market data used by leading DeFi applications such as Aave, Synthetic, Compound, and more. Powered by a multitude of professional, security-reviewed oracle nodes and premium data aggregators, these purpose-built price feeds provide broad market coverage on a wide array of assets and enable developers to rapidly create innovative smart contract applications that require a secure source of external market data. 

Chainlink Data Feeds are a community resource sponsored by a large collection of users and Chainlink, creating highly secure and decentralized oracle networks through the aggregation of user fees. With each additional user, existing and future users gain the benefits of a more cost-efficient and secure oracle network than they could afford on their own. As the DeFi ecosystem has grown, Chainlink Data Feeds have become a widely adopted solution that is lowering the barrier to creating highly secure financial smart contract applications.

The smart contract ecosystem is constantly evolving. As a result, Data Feeds within the Chainlink ecosystem are continuously evaluated for their usage and economic viability across all the blockchains and layer-2 networks they are deployed on.

Data Feeds with low or no usage or feeds that do not have a viable path to economic sustainability may be scheduled for deprecation. Doing so not only helps preserve blockchains as public goods by optimizing blockspace usage, but it helps reduce unnecessary costs incurred by Chainlink node operators. This process is part of a broader ecosystem shift towards Chainlink Economics 2.0, designed to maximize the adoption of the Chainlink protocol while optimizing for cost-efficiency and long-term economic sustainability. Over time, new Data Feeds may be launched or relocated to alternative blockchains/layer-2s that better reflect current user demand.

A list of Data Feeds designated for deprecation along with their corresponding shutdown date can be found in the Chainlink Documentation: https://docs.chain.link/docs/deprecating-feeds/

For status updates regarding Data Feeds, users should join the official Chainlink Discord and subscribe to the data-feeds-user-notifications channel: https://discord.gg/Dqy5N9UbsR

Developers are responsible for maintaining the security and user experience of their applications. They must also securely manage all interactions between their applications and third-party services.

In particular, developers implementing Chainlink Data Feeds in their code and applications are responsible for their application’s market integrity and code risks that may cause unanticipated pricing data behavior. For more information about developer responsibilities, please refer to: https://docs.chain.link/data-feeds/developer-responsibilities

Chainlink VRF brings secure random number generation to the blockchain. Chainlink VRF solves the difficult problem of providing an onchain source of randomness that is publicly verifiable to be authentic and tamper-proof. Many smart contracts are augmenting the value they can create by utilizing Chainlink VRF, specifically applications such as gaming dApps that must prove to their users that their source of randomness is provably fair and resistant to manipulation from any external entity. Chainlink VRF enables and accelerates the development of smart contracts focused on blockchain gaming, security, layer-two protocols, and various other use cases.

Chainlink Automation is a decentralized solution that enables projects to perform key smart contract functions and DevOps tasks in a highly reliable, trust-minimized, and cost-efficient manner. Individual developers, teams, and DAOs can utilize Chainlink Automation as an offchain computation layer to reliably perform key functions and unlock advanced utility.

A decentralized network of nodes provides trust-minimized and reliable automation with no single point of failure, mitigating risks around manual interventions or centralized servers. Projects using Chainlink Automation are able to reduce time spent on DevOps, eliminate automation infrastructure costs, and build faster and more efficiently.

Chainlink Proof of Reserve provides smart contracts with the data required to calculate the true collateralization of any onchain asset backed by offchain reserves such as stablecoins and cross-chain assets. Operated by a decentralized network of oracles, Chainlink Proof of Reserve enables the autonomous auditing of collateral used within DeFi in real-time, ensuring users’ funds are protected from unforeseen fractional reserve practices and other fraudulent activity from offchain custodians. This provides both the growing DeFi ecosystem and the traditional financial system a way to increase the transparency of operations with definitive onchain proof of any asset’s true collateralization.

The Cross-Chain Interoperability Protocol (CCIP) provides a universal, open standard for developers to build secure services and applications that can send messages, transfer tokens, and initiate actions across multiple blockchain networks.

CCIP provides smart contract developers a generalized, compute-enabled infrastructure for transferring data and smart contract commands across blockchain networks. CCIP will underpin a variety of cross-chain services, such as the Chainlink Programmable Token Bridge, which will empower users to move their tokens across any blockchain network in a highly secure, scalable, and cost-efficient manner.

DECO is a novel privacy-preserving oracle protocol that allows users to prove facts about their web (TLS) sessions to oracles without unveiling any confidential information onchain. 

Developed by researchers at Cornell University and acquired by Chainlink, this technology extends the data security capabilities of HTTPS and TLS, guaranteeing that data remains private and tamper-proof during its delivery from various private and premium data sources. It does so by employing advanced cryptography and zero-knowledge proofs from any server using HTTPS/TLS, without revealing that data to the outside world or even to the final computation using the data. DECO creates a new method of providing private and premium data across the internet while maintaining its confidentiality and security at previously unachievable levels.

This additional level of data security enables previously inaccessible data to be made accessible to both existing web systems and various blockchains and smart contracts through Chainlink oracles. Using DECO-enabled Chainlink nodes:

• Premium data sources that have so far been unable to place high-quality data on public blockchains due to confidentiality concerns will be able to provide data to various blockchains and DeFi protocols. 
• Enterprises will be able to prove the state of private data to other enterprises and blockchain records without revealing internal data onchain.
• Consumers will be able to prove personal data like identity or bank balances to smart contracts without giving applications full access to their personal accounts, maintaining their privacy.

Chainlink Data Streams provides low-latency delivery of market data offchain that you can verify onchain. With Chainlink Data Streams, decentralized applications (dApps) now have on-demand access to high-frequency market data backed by decentralized, fault-tolerant, and transparent infrastructure.

Any individual or group that needs real-world data to power and secure the execution of their smart contracts can benefit from Chainlink’s robust and customizable framework for creating decentralized oracle networks. Today, hundreds of teams working on dApps, blockchains, industry consortiums, enterprise projects, and more rely on Chainlink to provide tamper-proof inputs and outputs for their smart contracts. Chainlink has become the de facto oracle solution for the DeFi space, supporting top projects like Aave, Synthetix, and Compound, and securing billions in value across the sector.

If you’d like more information on how Chainlink could provide solutions for your project, join us in the Official Discord Channel and reach out through the integrations submission form.

Secure oracles that provide tamper-proof inputs and outputs for smart contracts are required for the vast majority of valuable smart contract use cases.

Robust and decentralized Chainlink Price Feeds for powering DeFi, verifiable randomness for onchain gaming, smart contract execution with Chainlink Automation, additional security and transparency with Chainlink Proof of Reserve, premium weather data for parametric insurance, cross-chain communication with CCIP, and enterprise blockchain middleware are just a small handful of applications powered by Chainlink’s oracle infrastructure.

Additionally, Chainlink oracle networks not only benefit onchain smart contracts but also benefit offchain systems, providing them with a reliable source of censorship-resistant and tamper-proof data that is cryptoeconomically secured. High-value enterprise backend systems can use Chainlink’s data as inputs to ensure only the highest quality data is being utilized to trigger mission-critical business functions. This greatly broadens the use case of oracles and can provide the global economy with even more verifiable data sources around the definitive state of the world. 

Explore the blog post 77+ Smart Contract Use Cases Enabled by Chainlink and the categories below for a deeper dive into applications of decentralized oracles: 

• Decentralized finance
• External payments
• NFTs, gaming and randomness
• Insurance
• Enterprise systems
• Supply chain
• Utilities
• Authorization and identity
• Government
• Sustainability
• Offchain computation

Decentralized finance (often referred to as DeFi) is a growing movement around recreating common financial instruments from traditional finance using decentralized infrastructure. Rather than needing centralized entities to facilitate the movement of financial markets, users can access, trade, and lend assets using open-source software running on decentralized networks. The result is self-running, peer-to-peer financial markets based on transparency, open access, and data-driven automation.

Chainlink oracle networks enable tamper-resistant and sustainable price feeds that are currently in use by several top DeFi applications to secure billions of dollars worth of locked value. By enabling smart contracts to access new forms of data as inputs, while retaining the underlying security and reliability guarantees of the smart contract, Chainlink plays a crucial role in the DeFi industry’s growth.

In the current price reference feed model, independent nodes in the Chainlink Network monitor for price changes offchain, trigger an update when the price change hits a defined threshold (e.g. 1%), fetch aggregated market prices from high-quality data providers, and then aggregate node responses to generate a highly available and manipulation-resistant price update onchain. Smart contracts can then access an extremely accurate price using a simple function call.

Some examples of price feed users include:

• Synthetic asset platforms that require the price of real-world assets in order to mint their representation onchain. These platforms use Chainlink reference contracts to create tokens tied to real-world assets, such as gold, indices, or even car loans.
• Lending and borrowing platforms that require a price feed to ensure the total value of the collateral. These platforms use Chainlink to issue and settle loans, liquidate collateral, and calculate interest payments.
• Stablecoins that require a price feed to assert the value of the underlying collateral backing the asset. These platforms use Chainlink to create stablecoins pegged to fiat currency, currency baskets, or commodities.
• Asset management platforms that require a reliable price feed for the critical rebalancing of asset ratios. These platforms use Chainlink to power a decentralized exchange (DEX), adjust capital pools, or facilitate multiple forms of payment.

Explore the expansive collection of Chainlink Price Feeds: data.chain.link

Chainlink has a variety of active channels where you can find more information about the latest Chainlink announcements, discover helpful technical resources, and connect with other members of our rapidly growing community. Below is a list of official Chainlink channels. As a security best practice, always double-check the URL that you are visiting to ensure you are accessing official Chainlink properties. Chainlink will never ask for your passwords, seed phrases, private keys, or other confidential information. 

• Blog: https://blog.chain.link/
• Discord: https://discord.com/invite/chainlink
• Docs: https://docs.chain.link/
• Events: https://events.chain.link/
• GitHub: https://github.com/smartcontractkit/chainlink
• Kakao: https://open.kakao.com/o/gWXAAf0b
• Lens Protocol: https://lenster.xyz/u/chainlink
• LinkedIn: https://www.linkedin.com/company/chainlink-labs/
• Newsletter: https://pages.chain.link/subscribe
• Reddit: https://www.reddit.com/r/Chainlink/
• TikTok: https://www.tiktok.com/@chainlinkofficial
• Twitch: https://www.twitch.tv/chainlinklabs
• @Chainlink Twitter: https://twitter.com/chainlink
• @ChainlinkLabs Twitter: https://twitter.com/chainlinklabs
• @SmartContract Twitter: https://twitter.com/SmartContract
• WeChat: https://blog.chain.link/chainlink-chinese-communities/
• YouTube: https://www.youtube.com/c/chainlink
• Telegram: https://t.me/chainlinkofficial

For status updates regarding Chainlink Data Feeds, users should join the official Chainlink Discord and follow the data-feeds channel: https://discord.gg/Dqy5N9UbsR

The Chainlink development team is continuously building the network and protocol. To keep up to date with current progress you can follow the Chainlink Github. You can find a full list of open roles on the Chainlink Labs careers page.

For inquiries related to security and support, please reach out to the admins of official Chainlink channels or email support@chain.link‍. You can also find more technical information in the documentation. 

Always practice a security mindset and ensure that users you are interacting with on community channels have verifiable trusted identities. You can confirm the accounts of official Chainlink community admin by clicking their names in the chat or viewing their handles under the official channel info.

There are numerous projects working on the development of the Chainlink ecosystem, including Chainlink Labs. You can find a full list of open roles on the Chainlink Labs careers page.