Introduction
On May 22, 2025, Maghnus Mareneck, co-executive of Interchain Labs, revealed that the Colombian government is collaborating with a bank consortium to test a CBDC for cross-border payment scenarios on the Cosmos network, choosing a private, permissioned node model and the IBC Eureka technology stack. [Source: news.bitcoin.com]
No DAO, no on-chain governance, just permissioned nodes and a distributed ledger. Who would have thought that Cosmos, dubbed the "decentralized Lego," would become the ideal partner for central bank digital currencies?
Cosmos: Building Blocks, A Perfectly Fitted Power Coat
Cosmos is not a public chain, but a complete toolbox for "chain building + inter-chain communication," designed for a multi-chain architecture. Compared to the standardized, open Ethereum, Cosmos's flexibility and controllability provide an ideal template for central banks to "customize a sovereign ledger".
Cosmos SDK: Assembling Sovereign Chains Like Lego
Cosmos SDK is a modular development framework that central banks can assemble as needed:
- Add account permissions and KYC modules
- Disable smart contract virtual machines to prevent "uncontrollable" contract deployments
- Add regulatory audit and targeted payment plugins
Tendermint BFT: Taking Turns as the 'Central Bank'
Cosmos uses Tendermint consensus, which doesn't rely on computing power for mining, but instead allows authorized validators to take turns producing blocks. Node members are controllable, with extremely low latency and strong block finality, naturally adapting to CBDC's real-time payment scenarios.
IBC: The 'TCP/IP' Between Chains
IBC is Cosmos's inter-blockchain communication protocol:
- Supports state proof and cross-chain asset transfer
- Zone chains are independent, exchanging authentication data packets when necessary
- Implements chain-level whitelisting and packet inspection for "controllable interoperability" rather than unordered interaction
Using this protocol and the ICS-20 standard, tokens like ATOM and OSMO can circulate freely among multiple Zones in the Cosmos ecosystem without bridging.
Hub-and-Zone: Refusing to Reinvent the Wheel L2
Cosmos's architecture is based on "Hub and Zone":
- Cosmos Hub is the earliest chain in the ecosystem, but not the "supreme commander"
- Zones refer to independent chains like Osmosis and Juno, each with its own ledger and validators
- They communicate through IBC without Hub intermediation
Each Zone is a "pluggable, self-maintained" sovereign chain that can interoperate without subordination.
Colombian Path: The Sovereignty Calculation Behind Technology Selection
Colombia's CBDC chain is essentially a Zone using Cosmos technology.
- Not dependent on Cosmos Hub
- Not directly interoperable with other DeFi ecosystems
- A closed permissioned chain, only borrowing Cosmos SDK, Tendermint, and IBC components
For the Colombian central bank, this is not "idealistic" decentralization, but a "instrumentalist" choice.
Cosmos and mBridge Crossroads: Balancing Cost, Efficiency, and Control
In the infrastructure selection for central bank digital currencies, Cosmos might not have expected to become one of the routes.
Currently, the leading route is the mBridge - a consortium chain network connecting CBDC networks (including 5 members from central banks and international organizations, with over 32 observer members) led by the Bank for International Settlements (BIS). Member countries' central banks establish Operator Nodes, resembling a joint central bank, and allow commercially licensed banks or settlement institutions to execute nodes for currency exchange.
The author compares mBridge, Cosmos, and mainstream cross-chain bridges as follows:
Why Did Colombia Not Choose mBridge, but Turn to Cosmos?
On one hand, mBridge is a product of great power competition, with slow technological update rhythm and high access barriers. On the other hand, Cosmos provides "out-of-the-box" technical components, allowing the construction of a local permissioned chain without complex negotiations or diplomatic coordination, while reserving future interoperability through IBC.
This better aligns with the current practical demands of Latin American economies:
- Limited budget, need for rapid construction
- Unwillingness to completely rely on alliances led by specific major powers
- Desire to find a balance between compliance control and blockchain innovation
If Colombia's pilot is successful, Cosmos may become a new path for medium and small economies to build sovereign digital currencies. A controllable, cost-acceptable, and technologically independent route may be replicated by more sovereign states in South America, Africa, and Southeast Asia. This is a typical victory of "technological pragmatism".
Conclusion
Cosmos provides a technical "neutrality" and "tailorability": it does not preset governance answers, nor does it reject centralized deployment.
Colombia has not joined Web3; it merely borrowed Cosmos. Without open nodes, on-chain governance, or connection to public chain ecosystems - this CBDC chain based on Cosmos is more like a refined and modified "sovereign monetary machine".
However, this "cooling and adaptation" of Web3 technology in real-world scenarios is also a certain acknowledgment of its engineering value.
