Monero 0.9.0 "Hydrogen Helix" Released

Posted by: Riccardo Spagni (fluffypony)

Summary of Changes

Too much to describe. Represents a major release in Monero's history, over a year-and-a-half in the making. Some highlights:

  • moved from in-RAM database to a backend-agnostic blockchain database
  • created an LMDB blockchainDB implementation (with the help of Howard Chu, the creator of LMDB)
  • created a BerkeleyDB blockchainDB implementation
  • created an OS-agnostic raw blockchain format
  • built tools to convert between blockchain implementations, as well as import and export them
  • added ARM support
  • brought back 32-bit support (WIP)
  • added QoS (bandwidth control)
  • added OpenAlias support
  • fixed all (previously broken) unit tests and core tests
  • implemented daemonize for proper backgrounding of the Monero daemon
  • drastically increased sync speed
  • included block headers in the source
  • designed and implemented a stealth payment ID scheme
  • designed and implemented a unified address+payment ID scheme
  • implemented a hard fork mechanism
  • changed the block time to 2 minutes
  • implemented the MRL-0001 and MRL-0004 recommendations
  • added tons of simplewallet / rpcwallet / daemon commands
  • added a dust handler to simplewallet
  • created a multilanguage mechanism, implemented in simplewallet
  • bug fixes, bug fixes, bug fixes
  • completely overhauled the CMake (with the help of Kitware, the creators of CMake)
  • added a bad peer auto-banning mechanism
  • refactored a ton of code, added a ton of comments
  • added a core crypto implementation based on SUPERCOP ref10
  • switched to a triangular distribution for output selection
  • added multiple new mnemonic wordlists, including Russian and Italian
  • created a "trusted daemon" system for remote daemon use

In total this represents 922 commits worth of work by 9 contributors. This will probably be the biggest release in Monero's history, everything from here on out can be done as faster point releases.

Updating: Blockchain Conversion

It is highly recommended that you delete the contents of your Monero working directory and sync from scratch. This directory can be found in ~/.bitmonero on Linux and OS X, and on Windows in \Users\username\AppData\Roaming\bitmonero or \ProgramData\bitmonero.

Syncing from scratch is EXTREMELY fast in this version, pretty much at bittorrent speeds, and will leave you with a fully verified blockchain.

Alternatively: if you want to grab the bootstrap (NOTE: there is a new bootstrap format!) off the website then you can get it at - once downloaded you can import it with blockchain_import --input-file /path/to/your/download.raw. If you're particularly brave you can pass the --verify 0 flag to skip verification during import.

If you REALLY want to convert your old blockchain: you can either use the blockchain_converter tool, or you can use blockchain_export to create a blockchain.raw, followed by blockchain_import to import it into the new LMDB format.

Download Hashes

If you would like to verify that you have downloaded the correct file, please use the following SHA256 hashes:

  •, c61284c4d5f78db2bc2072bef76f2b539293cca74bdd3fb9536a35ca54b4fd2e
  • monero.linux.x64.v0-9-0-0.tar.bz2, 655875a899aded6d63f99c5dfea6a45b3e77533bb2173e63612646ec7ac97100
  • monero.mac.x64.v0-9-0-0.tar.bz2, fce5140d9cb38d62ad1b9f1b0d06feaa209433f9ec542b8d368ef9e0da431b78

Post tags : Monero Software Releases