Cardano native oracle · 2021 to 2026
Data infrastructure for Cardano. Now open source.
Charli3 was the data infrastructure connecting builders on the Cardano blockchain to accurate, reliable, and secure data in an EUTXO format consumable by their contracts. Unlike many other decentralized oracle solutions, Charli3 went all-in on the Cardano ecosystem, pioneering many firsts along the way and supporting the ecosystem to get to the next phase of adoption. Operations ceased in May 2026. The contracts, SDKs and node software remain public, documented and free to run.
Operations ceased May 2026Milestones
$50M+ secured
At peak, C3 data infrastructure secured over USD $50M
13 Catalyst projects delivered
2 pending, 1 abandoned when the company ceased operations
2 audits passed
CertiK (2023) and Anastasia Labs (2025)
First push oracle on Cardano
Data supplied at a custom set interval. MVP 2021, production Oct 2022
First pull oracle on Cardano
Data supplied on request by contracts on chain, updated next block. 2025
First Proof of Reserve on Cardano
Securing $10M+ USD for the USDM stablecoin, including integrations with multiple EURO and US banks
First Oracle Validation service
On-chain records verifying off-chain records, for example identity checks
First L2 Partnerchain MVP
Oracle partnerchain with 500K+ data feeds. Funding ran out in 2026 before production release
First block-accurate token price API
Tracking movement of liquidity pools between blocks, providing 17K+ Cardano token data more accurately than any solution in the world (closed source, available for sale)
3+ years of subsidized public data
Public data infrastructure subsidized to support the growth of the ecosystem and new builders
Among the first on Cardano
One of the first protocols on Cardano, one of the first smart contracts on chain, and the first decentralized oracle solution on the Radix chain (Religant)
Status
Charli3 no longer operates oracle feeds, runs nodes, or offers commercial services. Hosted services, including the Token Data API, have been shut down. Charli3 does not provide support or guarantees for the software below.
Anyone can deploy and operate the oracle infrastructure independently. Everything needed to do so is in the documentation and the repositories.
How a Charli3 oracle works
Data providers
Exchanges, APIs and reserve attestations supply raw values.
Independent nodes
Decentralized node operators fetch, validate and sign each value.
On-chain consensus
Smart contracts aggregate node submissions into a single verified value.
Standard datum
A CBOR-formatted oracle datum any Cardano contract can read.
Components available
Push Oracle
Periodic, scheduled data feeds published on chain by a network of nodes using a consensus algorithm. Contracts, SDK and node software.
Push Oracle docs →Pull Oracle (ODV)
On-demand validation. Request-based data access where a consumer pays for a fresh datum when it needs one. Client, contracts, SDK and node.
Pull Oracle docs →Node operator guides
How to run a Charli3 node: data source connections, configuration and operations for both oracle types.
Node operators →SDK and platform tools
Python-based SDKs for platform operators to deploy and manage oracle networks on Cardano.
Get started →Open source repositories
| Repository | Contents | License |
|---|---|---|
| charli3-push-oracle-contracts | Validators and minting policies | MIT |
| charli3-push-oracle-sdk | Transaction building, oracle deployment, configuration | AGPL-3.0 |
| charli3-push-oracle-node | Data source connections and node logic | MIT |
| charli3-pull-oracle-client | Client library for requesting and consuming feeds | MIT |
| charli3-pull-oracle-contracts | Validators and minting policies | AGPL-3.0 |
| charli3-pull-oracle-sdk | Transaction building, oracle deployment, configuration | AGPL-3.0 |
| charli3-pull-oracle-node | Data source connections and off-chain integration | MIT |
Full list and licensing details: docs.charli3.io/oracles/open-source-project
A note from the team
Charli3 was a pioneering team of technical builders. We delivered one of the industry's most reliable decentralized oracle infrastructures. That is why Charli3 is one of the few oracles, if not the only one, to hold 99.99% uptime.
The incumbent standard for responding to a missed data update is six hours or more. We measured ours in seconds.
Much of that reliability came from the technical foundation of Cardano. We built on a chain that was in constant development and adapted to technological uncertainty every step of the way. That was the mission, and it was an exciting one. Our team believes Cardano is the best architecture for enterprise-grade solutions that require a public blockchain.
The company's vision was a bet on Cardano scaling. The bet was risky. Other oracle providers hopped from chain to chain and were unwilling to commit to Cardano. Charli3 became the sole provider of data on the chain. Early builders could integrate accurate, reliable and secure data feeds without building one of blockchain's most complex and vulnerable pieces of infrastructure themselves.
We were the unseen infrastructure behind builders. Our community data feeds subsidized early projects so they could scale and focus on their products instead of data integration and security. Charli3 was rarely in the news. That meant everything was functioning properly in the back end.
The company behind Charli3 received modest funding from Cardstarter in 2021, under $850K. We did not raise through our token launch in February 2022 and did not benefit from any other token sale. Our utility token was an economic necessity for a true decentralized data infrastructure.
The decision to cease operations is documented in our X post. The short version: we chose to absorb the cost of being first to market and to build a moat in Cardano. The demand for our services was never high enough to support a profitable decentralized oracle. Today, there is no native oracle on Cardano for this very reason. In 2026, the team decided the best move was to open source. Our mission was to enable access to accurate, reliable and secure data on Cardano. Open sourcing is aligned with that mission.
We still believe in the vision of Cardano. From a technical standpoint, our team has no regrets. We are proud of the production releases we shipped from 2022 to 2026, including a weekend hackathon in 2026 that produced 16 production-grade projects.
Thank you to our builders, community, customers, developers and supporters through the years. Our team could not have shipped this infrastructure without your Catalyst grant support.
Contributors
Charli3 is the collaborative effort of many talented developers and teams, including but not limited to the following labs. We are very grateful for their contributions over the years.
History
- 2021Charli3 founded. One of the first projects built on Cardano. Modest raise through our accelerator.
- Feb 2022C3 token launched as a Cardano native token (CNT).
- 2022–26Push oracle, pull oracle (ODV), proof of reserve and partner chain solutions shipped to production on EUTXO infrastructure. 13 Catalyst projects delivered, 2 pending, 1 abandoned when the company ceased operations.
- Jan 2025Open-sourcing of the oracle stack begins.
- May 2026Operations cease. Repositories and documentation left public for the community.
Contact
You can still reach us through our official X account, @Oraclecharli3, for questions about deploying or operating the infrastructure, or for contract support.