Architecture
Chromia organizes blockchains and dapps into clusters with reliable consensus, secure anchoring, and elastic resources. This setup keeps performance high, preserves tamper-evident data, and lets chains and dapps coordinate smoothly.
Nodes
A node in the Chromia network is a computer, either a virtual or physical server, that runs the core Chromia software known as Postchain and the open-source relational database, PostgreSQL. Each node runs Postchain plus PostgreSQL, exposes REST endpoints for GTX transactions, executes Rell logic inside isolated dapp containers, and keeps per-dapp histories so state can be reconstructed at any block height. Nodes also handle automatic indexing, query execution, and dynamic block production parameters.
Platform architecture
Chromia splits the network into two types of clusters. System clusters run the core services that keep Chromia organized and secure, while dapp clusters host individual applications, each with dedicated computing resources so spikes in one app don't slow the rest. A built-in anchoring process routinely snapshots every chain and stores those proofs on higher level chains (and even on Ethereum), giving the network a trustworthy trail it can fall back on if something goes wrong.
Chains
Chromia relies on a family of specialized blockchains, each with a focused role so upgrades and troubleshooting stay scoped:
- Directory Chain – records the network's topology, dapp code, and configuration so clusters can be restored quickly.
- Economy Chain – manages hosting prices, provider rewards, and payments tied to leased resources.
- Token Chain – standardizes FT4-compatible token creation, account strategies, and bridge automation.
- Cluster Anchoring Chains – collect block headers from every dapp chain in a cluster.
- System Anchoring Chain – batches those headers and anchors them to higher-trust destinations.
- Transaction Submitter Chain – periodically submits Chromia's state to Ethereum for external anchoring.
Governance
Chromia's governance model keeps the network decentralized without overwhelming newcomers: dedicated provider teams operate clusters, propose upgrades, and vote on changes so dapps can rely on predictable rules. Today there are 15 system providers and 6 node providers, and system-level changes need a two-thirds supermajority to pass. The Directory Chain tracks approved code and configuration, while public metrics—like the Nakamoto coefficients of 6 (system) and 3 (dapp) clusters—show how resistant each cluster is to collusion.
Cross-chain interoperability
Chromia was built to talk to other blockchains, so projects can plug into existing ecosystems instead of starting from scratch. The Ethereum Interoperability Framework pairs a Rell module with EVM smart contracts to run the H-Bridge, which locks assets on one chain and mints their equivalents on another. CHR already moves between Chromia's Economy Chain, Ethereum, and BNB Chain, with support for stablecoins like USDT/USDC on the roadmap, and builders can follow the bridge deployment and client guides to integrate the same flow into their own dapps.
For deeper dives into each topic, continue with the Architecture section in Fundamentals.