Alephium Activates Danube Upgrade, Doubling Throughput and Simplifying UX

Alephium has officially launched its highly anticipated Danube upgrade on mainnet. Activated on July 15 at 12:00 UTC, the update marks the most significant milestone in Alephium’s development to date, delivering major improvements to performance, user experience, and developer tooling.

The Danube upgrade slashes block times in half to 8 seconds, bringing Alephium’s confirmation speeds in line with leading Proof of Stake networks, while increasing network throughput to 20,000+ transactions per second (TPS). Optimizations to Alephium’s BlockFlow consensus also accelerate node synchronization by up to 3x, making the network more accessible for operators.

“Danube is the moment everything clicks,” said Alephium COO Maud Bannwart. “We’re not just improving UX—we’re delivering a Web2-grade experience natively on a decentralized, energy-efficient Proof of Work chain.”

Seamless Sharding, Seedless Onboarding

One of Danube’s headline features is Groupless Addresses, which abstract away shard logic and allow users to interact with the entire network using a single wallet address. Combined with support for Passkeys (Face ID, Touch ID, YubiKey), Alephium is eliminating some of Web3’s most intimidating entry barriers: complex addresses and seed phrases.

These UX enhancements are designed to deliver a seamless, intuitive experience while preserving the decentralization and security benefits of Proof of Work—a balance few chains have achieved.

Tools for the Next Generation of dApps

For developers, Danube introduces Chained Transactions, which allow smart contracts to reuse assets and outputs across multiple function calls in a single transaction. This makes it easier to build complex applications such as token swaps or multi-step workflows.

Additional upgrades include a smarter virtual machine with 256-bit bitwise operations, automatic dust handling, and enhanced contract syntax via Alephium’s native programming language, Ralph.

The result? A development environment that reduces friction, minimizes bugs, and improves smart contract performance—all on a stateful UTXO (sUTXO) model known for safety and composability.

Category	Feature	Description	Benefits
User Experience (UX)	Groupless Addresses	Single address works across all shards; wallets auto-route and unify balances.	Eliminates shard complexity; seamless scalability like non-sharded chains.
User Experience (UX)	Passkey Support	Seedless onboarding with Face ID, Touch ID, or YubiKey; seed phrases optional.	Frictionless login; safer onboarding for mainstream users.
Performance	Faster Block Times	Reduced from 16s to 8s; enables ~2 blocks/second throughput.	Quicker confirmations; 20,000+ TPS capacity.
Performance	Sync Protocol v2	Skeleton-first sync; then parallel data download.	3x faster node sync; better decentralization.
Development (DevX)	Chained Transactions	Smart contracts can reuse assets/functions across multiple calls.	Simplifies complex workflows (e.g. swaps, dApps).
Development (DevX)	Smarter Tools & Contracts	New VM ops, dust auto-handling, 256-bit ops, Ralph upgrades.	Reduces boilerplate; enables advanced logic.
Consensus & Network	Optimized BlockFlow	“Optimistic” execution; efficient messaging and parallel TXs.	Faster execution; reduced orphan rates.
Security & Interoperability	BLS Signature Support	Enables secure cross-chain bridges and integrations.	Opens up multi-chain access.
Other	Storage Optimization	Reduced disk usage and faster data retrieval.	Lower node barriers; smoother operations.

Why It Matters

Alephium’s approach contrasts sharply with rollup-centric Layer 2 solutions and stateless account abstraction experiments. Instead, Danube bakes scalability, interoperability, and usability directly into the Layer 1 protocol.

With the second-highest TVL among Proof of Work chains, Alephium’s blend of smart contracts, sharding, and energy-efficient consensus puts it in a unique position to attract dApps, DeFi platforms, and real-world integrations—all without sacrificing decentralization.

“Web3 was supposed to be better. With Danube, it finally is,” the Alephium team said in a statement.