you must add the following line to your bitcoin.conf file:


I strongly recommend also adding:


If you see messages in your logs about truncated messages whilst syncing, you may need to increase the timeout (in seconds) further.

Version 1.20.0 (21 Oct 2021)

  • get blocks via the REST API from bitcoind, and process them incrementally and in a separate thread
  • support for TSC merkle proofs (AustEcon)
  • sockets tweak (rt1212121)

Version 1.19.0 (11 Jun 2021)

  • disconnect excessive resource usage sessions faster (SomberNight)
  • better handling of task groups to reduce memory usage and report errors properly
  • add MAX_RECV environment variable defaulting to 5 million bytes

Version 1.18.1 (26 Apr 2021)

  • Fix unclean and stalled shutdowns
  • Cleanup lock handling
  • Process blocks one at a time
  • Remove dead code

Version 1.17.0 (04 Feb 2021)

  • Fix a couple of issues raised by pylint

Version 1.16.0 (03 Feb 2021)

  • Require Python 3.8.
  • Bitcoin only (BSV).
  • Disable resource limits for private sessions (ghost43).
  • Various bug fixes (jtarthur, ghost43) particularly in peer discovery.
  • other: AustEcon, Roger Taylor, Franco Benner

Version 1.15.0 (27 May 2020)

  • switch to 5-byte txnums to handle larger blockchains. Upgrade DBs during restart.
  • accurate clearing of stale caches
  • coin additions / updates: NavCoin + Hush + VersusCoin + Zero (cipig), DashRegtest (colmenero), Quebecoin (morinpa), Primecoin (Sunny King), multiple (Panagiotis David), RVN (standard-error), Sumcoin
  • other: Jeremy Rand, Jin Eguchi, ddude, Jonathan Cross, Carsen Klock, cipig

Version 1.14.0 (19 Jan 2020)

  • require Python 3.7
  • support for Bitcoin SV Genesis activation
  • DB upgrade to allow for larger transactions. Your DB will automatically upgrade when starting, the upgrade should take approximately 15 mintues.
  • fix server shutdown process
  • fix cache race condition (issue #909)
  • faster initial sync
  • coin additions / updates: Emercoin (yakimka), Feathercoin (wellenreiter01), Peercoin (peerchemist), Namecoin (JeremyRand), Zcoin (a-bezrukov), Simplicity, Mice (ComputerCraftr), Sibcoin testnet (TriKriSta), Odin (Manbearpixel),
  • other: h2o10, osagga, Sombernight, breign, pedr0-fr, wingsuit

Version 1.13.0 (26 Sep 2019)

  • daemon: use a single connection for all requests rather than a connection per request. Distinguish handling of JSON and HTTP errors
  • recognise OP_FALSE OP_RETURN scripts as unspendable
  • peers - attempt to bind to correct local IP address
  • improve name support (domob1812)
  • coin additions / updates: BitZeny (y-chan), ZCoin (a-bezrukov), Emercoin (yakimka), BSV (Roger Taylor), Bellcoin (streetcrypto7), Ritocoin (traysi), BTC (Sombernight), PIVX (mrcarlanthony), Monacoin (wakiyamap)), NamecoinRegtest (JeremyRand), Axe (ddude1), Xaya (domob1812), GZRO (MrNaif2018), Ravencoin (standard-error)
  • other: gits7r

Version 1.12.0 (13 May 2019)

  • require aiorpcX 0.18.1. This introduces websocket support. The environment variables changed accordingly; see SERVICES and REPORT_SERVICES.
  • work around bug in recent versions of uvloop
  • aiorpcX upgrade fixes from Shane M
  • coin additions / updates: BitcoinSV, Bolivarcoin (Jose Luis Estevez), BTC Testnet (ghost43), Odin (Pixxl)

Version 1.11.0 (18 Apr 2019)

  • require aiorpcX 0.15.x
  • require aiohttp 3.3 or higher; earlier versions had a problematic bug
  • add REQUEST_TIMEOUT and LOG_LEVEL environment variables
  • mark 4 old environment variables obsolete. ElectrumX won’t start until they are removed
  • getinfo local RPC cleaned up and shows more stats
  • miscellaneous fixes and improvements
  • more efficient handling of some RPC methods, particularly blockchain.transaction.get_merkle()
  • coin additions / updates: BitcoinSV scaling testnet (Roger Taylor), Dash (zebra lucky),
  • issues resolved: #566, #731, #795

Version 1.10.1 (13 Apr 2019)

  • introduce per-request costing. See environment variables documentation for new variables COST_SOFT_LIMIT, COST_HARD_LIMIT, REQUEST_SLEEP, INITIAL_CONCURRENT, BANDWIDTH_UNIT_COST. Sessions are placed in groups with which they share some of their costs. Prior cost is remembered across reconnects.
  • require aiorpcX 0.13.5 for better concurrency handling
  • require clients use protocol 1.4 or higher
  • handle transaction.get_merkle requests more efficiently (ghost43)
  • Windows support (sancoder)
  • peers improvements (ghost43)
  • report mempool and block sizes in logs
  • electrumx_rpc: timeout raised to 30s, fix session request counts
  • other tweaks and improvements by Bjorge Dijkstra, ghost43, peleion,
  • coin additions / updates: ECA (Jenova7), ECCoin (smogm), GXX (DEVCØN), BZX (2INFINITY), DeepOnion (Liam Alford), CivX / EXOS (turcol)

Version 1.10.0 (15 Mar 2019)

  • extra countermeasures to limit BTC phishing effectiveness (ghost43)
  • peers: mark blacklisted peers bad; force retry blacklisted peers (ghost43)
  • coin additions / updates: Monacoin (wakiyamap), Sparks (Mircea Rila), ColossusXT, Polis, MNPCoin, Zcoin, GINCoin (cronos), Grosetlcoin (gruve-p), Dash (konez2k), Bitsend (David), Ravencoin (standard-error), Onixcoin (Jose Estevez), SnowGem
  • coin removals: Gobyte, Moneci (cronos)
  • minor tweaks by d42
  • issues fixed #660 - unclean shutdowns during initial sync

Version 1.9.5 (08 Feb 2019)

  • server blacklist logic (ecdsa)
  • require aiorpcX 0.10.4
  • remove dead wallet code
  • fix #727 - not listing same peer twice

Version 1.9.4 (07 Feb 2019)

  • require aiorpcX 0.10.3
  • fix #713

Version 1.9.3 (05 Feb 2019)

  • ignore potential sybil peers
  • coin additions / updates: BitcoinCashABC (cculianu), Monacoin (wakiyamap)

Version 1.9.2 (03 Feb 2019)

  • restore protocol version 1.2 and send a warning for old BTC Electrum clients that they need to upgrade. This is an attempt to protect users of old versions of Electrum from the ongoing phishing attacks
  • increase default MAX_SEND for AuxPow Chains. Truncate AuxPow for block heights covered by a checkpoint. (jeremyrand)
  • coin additions / updates: NMC (jeremyrand), Dash (zebra-lucky), PeerCoin (peerchemist), BCH testnet (Mark Lundeberg), Unitus (ChekaZ)
  • tighter RPC param checking (ghost43)

Version 1.9.1 (11 Jan 2019)

Version 1.9.0 (10 Jan 2019)

  • minimum protocol version is now 1.4
  • coin additions / updates: BitcoinSV, SmartCash (rc125), NIX (phamels), Minexcoin (joesixpack), BitcoinABC (mblunderburg), Dash (zebra-lucky), BitcoinABCRegtest (ezegom), AXE (slowdive), NOR (flo071), BitcoinPlus (bushsolo), Myriadcoin (cryptapus), Trezarcoin (ChekaZ), Bitcoin Diamond (John Shine),
  • close #554, #653, #655
  • other minor tweaks (Michael Schmoock, Michael Taborsky)

Neil Booth