Jonas Schnelli presented to Bitcoin Meetup Switzerland on the upcoming Bitcoin Core 0.14 release. The update skips flashy new features but packs optimization work that most software companies avoid. F
Jonas Schnelli presented to Bitcoin Meetup Switzerland on the upcoming Bitcoin Core 0.14 release. The update skips flashy new features but packs optimization work that most software companies avoid. From a user perspective, there's nothing obvious here, but the improvements help the software run better across different hardware configurations.
"What we have done mainly is what you can never do in normal software projects, which is mainly refactoring [and improving] performance," Schnelli said. "This was the main focus for [Bitcoin Core] 0.14. [It's] a bit boring if you're looking for new features."
Schnelli brings two decades of software contracting experience to the project. He explained why corporations pass on this work. In competitive markets, companies don't allocate resources for refactoring and performance enhancement because the return isn't measured in user-visible features. "This is important if you want to survive the next years, but [there are] no features coming out of it directly," he said. The technical improvements include a new signature cache, an extensive network refactor, and various optimizations and code cleanup.
Fee estimation matters more in the ecosystem than before. As blocks fill up, transaction fees have become central to network operations. Miners now pocket over 1 BTC in transaction fees per block on top of the 12.5 BTC subsidy. Wallet providers throughout the ecosystem rely on Bitcoin Core's fee estimation model when building their own fee calculations. Bitcoin Core remains the most used resource for fee estimation.
Core 0.14 improves the fee estimation mechanism. The GUI's default confirmation target drops from 25 blocks to 6. Users can opt into replace-by-fee (RBF) at startup to resend transactions without mining penalties, though it defaults to off. A new bumpfee RPC command lets users accelerate stuck transactions if RBF is enabled. The mempool persists across shutdowns now, so nodes retain transaction data even after restart.
The blockchain swelled past 100GB, creating headaches for new users. Anyone downloading everything from block one faces a grueling initial sync. Many old blocks store data nodes don't require. Schnelli explained: "Once you have built the UTXO set, which is the set of coins that are not spent right now, you can throw away the old blocks." He added, "You only need them for other nodes who want to become full nodes."
Pruning allows users to shrink the full chain down to 550MB or more while maintaining a functional full node. Bitcoin Core 0.11 introduced automatic pruning that runs in the background. Version 0.14 adds manual pruning capabilities, letting users prune old blocks themselves via RPC command whenever they choose. As Schnelli put it, "pruned nodes will perform all of the normal functions of a full node with the exception of transmitting old blocks to new nodes that are syncing with the blockchain for the first time."
The release includes several other refinements. Users can toggle network activity to conserve bandwidth. Importing multiple keys or watch-only addresses now works faster than before. New warnings alert users when scammers try to trick them into typing dangerous console commands.
