Coinbase Opened Base Testnet in a Bid to Build on Ethereum

Coinbase announced and opened the testnet for Base, an Ethereum layer-2 network built with Optimism’s open-source OP Stack, on February 23, 2023. The company said Base would become a home for its own onchain products while remaining available to outside application developers.

The development mattered because Coinbase was moving beyond operating an exchange, wallet and developer services into building blockchain infrastructure. It was also an institutional endorsement of Ethereum’s rollup-centered scaling strategy and Optimism’s proposal for multiple networks constructed from shared software.

The event-day record supports a testnet launch—not a production network, demonstrated adoption or completed decentralization. Coinbase had not provided a specific mainnet date, and the company’s claims about security, cost and accessibility remained objectives to be tested.

From trading venue to network builder

Base was designed as a separate execution environment connected to Ethereum. The layer-2 model sought to move activity away from Ethereum’s more constrained base layer while retaining a relationship with Ethereum for settlement and security. Coinbase described Base as fully compatible with the Ethereum Virtual Machine and intended to make existing Ethereum development tools easier to use at lower cost.

Those descriptions established the intended architecture, not measured performance. A testnet gives developers a place to deploy applications and identify software or configuration problems without treating the environment as a finished venue for production assets.

Coinbase also announced the Base Ecosystem Fund to support early-stage projects building on the network. Together, the network and fund showed that the company wanted to influence both the infrastructure and application layers of the onchain economy. The strategy depended on developers choosing to build there and Coinbase eventually integrating Base with its consumer and institutional products; neither outcome was established on February 23.

The Optimism relationship

Coinbase said Base used the MIT-licensed OP Stack and that it was joining Optimism as the stack’s second core development team. Optimism separately confirmed that Coinbase would contribute to the codebase while operating Base as a new layer-2 network built from it.

The partnership was intended to support a broader “Superchain”: multiple layer-2 networks sharing standards and, eventually, infrastructure for interoperability. Optimism said Base would contribute an unspecified portion of transaction-fee revenue to the Optimism Collective treasury. The February 23 records did not supply a fixed percentage, and no production transaction revenue existed to measure from the newly opened testnet.

Shared bridging, sequencing and composability were forward-looking goals. They should not be read as features that had already been delivered across independent networks.

Decentralization remained unfinished

Coinbase said it was incubating Base internally and planned to decentralize the network progressively. A companion Base document acknowledged that the implementation was not yet fully decentralized and outlined goals involving fault proofs, distributed upgrade authority and shared sequencing.

The roadmap aimed to move Base and Optimism Mainnet from what the project called Stage 0 rollups toward Stage 1 during 2023, followed by Stage 2 during 2024. Those labels and dates were project targets, not verified milestones on February 23. The launch therefore combined open-source code and permissionless-development ambitions with material reliance on the companies building and operating the early system.

That tension was central to the announcement’s significance. Coinbase could bring engineering resources and product distribution to Ethereum scaling, but its involvement also raised questions about operational control, upgrade authority and whether promised decentralization would occur.

No Base network token

Coinbase explicitly said it had no plans to issue a new Base network token. That limited what could responsibly be inferred from the announcement: it was not a token sale, an airdrop commitment or a new investable asset issued by Coinbase.

The defensible February 23 conclusion is narrower. Coinbase opened a functioning development test environment and committed engineering resources to the OP Stack. Mainnet reliability, fees under sustained use, application demand, governance and decentralization all required later evidence.