Protocol and network related changes:

• Add a new checkpoint at block height 382320 (#555)
• Implement BIP0065 which includes support for version 4 blocks, a new consensus opcode (OP_CHECKLOCKTIMEVERIFY) that enforces transaction lock times, and a double-threshold switchover mechanism (#535, #459, #455)
• Implement BIP0111 which provides a new bloom filter service flag and hence provides support for protocol version 70011 (#499)
• Add a new parameter --nopeerbloomfilters to allow disabling bloom filter support (#499)
• Reject non-canonically encoded variable length integers (#507)
• Add mainnet peer discovery DNS seed (seed.bitcoin.jonasschnelli.ch) (#496)
• Correct reconnect handling for persistent peers (#463, #464)
• Ignore requests for block headers if not fully synced (#444)
• Add CLI support for specifying the zone id on IPv6 addresses (#538)
• Fix a couple of issue where the initial block sync could stall (#518, #229, #486)
• Fix an issue which prevented the --onion option from working as intended (#446)

Transaction relay (memory pool) changes:

• Require transactions to only include signatures encoded with the canonical 'low-s' encoding (#512)
• Add a new parameter --minrelaytxfee to allow the minimum transaction fee in BTC/kB to be overridden (#520)
• Retain memory pool transactions when they redeem another one that is removed when a block is accepted (#539)
• Do not send reject messages for a transaction if it is valid but causes an orphan transaction which depends on it to be determined as invalid (#546)
• Refrain from attempting to add orphans to the memory pool multiple times when the transaction they redeem is added (#551)
• Modify minimum transaction fee calculations to scale based on bytes instead of full kilobyte boundaries (#521, #537)

Implement signature cache:

• Provides a limited memory cache of validated signatures which is a huge optimization when verifying blocks for transactions that are already in the memory pool (#506)
• Add a new parameter --sigcachemaxsize which allows the size of the new cache to be manually changed if desired (#506)

Mining support changes:

• Notify getblocktemplate long polling clients when a block is pushed via submitblock (#488)
• Speed up getblocktemplate by making use of the new signature cache (#506)

RPC changes:

• Implement getmempoolinfo command (#453)
• Implement getblockheader command (#461)
• Modify createrawtransaction command to accept a new optional parameter locktime (#529)
• Modify listunspent result to include the spendable field (#440)
• Modify getinfo command to include errors field (#511)
• Add timestamps to blockconnected and blockdisconnected notifications (#450)
• Several modifications to searchrawtranscations:
  • Accept a new optional parameter vinextra which causes the results to include information about the outputs referenced by a transaction inputs (#485, #487)
  • Skip entries in the mempool too (#495)
  • Accept a new optional parameter reverse to return the results in reverse order (most recent to oldest) (#497)
  • Accept a new optional parameter filteraddrs which causes the results to only include inputs and outputs which involve the provided addresses (#516)
• Change the notification order to notify clients about mined transactions (recvtx, redeemingtx) before the blockconnected notification (#449)
• Update verifymessage RPC to use the standard algorithm so it is compatible with other implementations (#515)
• Improve ping statistics by pinging on an interval (#517)

Websocket changes:

• Implement session command which returns a per-session unique id (#500, #503)

btcctl utility changes:

• Add getmempoolinfo command (#453)
• Add getblockheader command (#461)
• Add getwalletinfo command (#471)

Notable developer-related package changes:

• Introduce a new peer package which acts a common base for creating and concurrently managing bitcoin network peers (#445)
  • Various cleanup of the new peer package (#528, #531, #524, #534, #549)
• Blocks heights now consistently use int32 everywhere (#481)
• The BlockHeader type in the wire package now provides the BtcDecode and BtcEncode methods (#467)
• Update wire package to recognize BIP0064 (getutxo) service bit (#489)
• Export LockTimeThreshold constant from txscript package (#454)
• Export MaxDataCarrierSize constant from txscript package (#466)
• Provide new IsUnspendable function from the txscript package (#478)
• Export variable length string functions from the wire package (#514)
• Export DNS Seeds for each network from the chaincfg package (#544)
• Preliminary work towards separating the memory pool into a separate package (#525, #548)

Misc changes:

• Various documentation updates (#442, #462, #465, #460, #470, #473, #505, #530, #545)
• Add installation instructions for gentoo (#542)
• Ensure an error is shown if OS limits can't be set at startup (#498)
• Tighten the standardness checks for multisig scripts (#526)
• Test coverage improvement (#468, #494, #527, #543, #550)
• Several optimizations (#457, #474, #475, #476, #508, #509)
• Minor code cleanup and refactoring (#472, #479, #482, #519, #540)

Contributors (alphabetical order):

• Ben Echols
• Bruno Clermont
• danda
• Daniel Krawisz
• Dario Nieuwenhuis
• Dave Collins
• David Hill
• Javed Khan
• Jonathan Gillham
• Joseph Becher
• Josh Rickmar
• Justus Ranvier
• Mawuli Adzoe
• Olaoluwa Osuntokun
• Rune T. Aune

MSI Checksums:

SHA256(btcd_standalone_0.12.0-beta_x64.msi)= 024274804600e0a37ba5e7ac5abc9fdfe91b071e92c9251f38f01bec6785fb77
SHA256(btcd_standalone_0.12.0-beta_x86.msi)= b122bb7cd29e0e5e32ada279a12eeef3d44d58f3bb377ea7ce8b1f42ca0bdba3
SHA512(btcd_standalone_0.12.0-beta_x64.msi)= 725266286cb5ba62d435b992353b83aef4a3586e5ee9aeecfcc90b8026225f12c081471d56fb0f02d92ca5d92965eb99429209125b108c47599c8b1b619fb852
SHA512(btcd_standalone_0.12.0-beta_x86.msi)= d2849eef7cce9ec88a9538940c3ebfb08c2ecbf4be88f4029552bac5db2cdc203e31e8a401cf54dab694d4f49dd640bc8bb962cb5d70227bde91d785364823cb

Protocol and network related changes:

• Use correct sub-command in reject message for rejected transactions (#436, #437)
• Add a new parameter --torisolation which forces new circuits for each connection when using tor (#430)

Transaction relay (memory pool) changes:

• Reduce the default number max number of allowed orphan transactions to 1000 (#419)
• Add a new parameter --maxorphantx which allows the maximum number of orphan transactions stored in the mempool to be specified (#419)

RPC changes:

• Modify listtransactions result to include the involveswatchonly and vout fields (#427)
• Update getrawtransaction result to omit the confirmations field when it is 0 (#420, #422)
• Update signrawtransaction result to include errors (#423)

btcctl utility changes:

• Add gettxoutproof command (#428)
• Add verifytxoutproof command (#428)

Notable developer-related package changes:

• The btcec package now provides the ability to perform ECDH encryption and decryption (#375)
• The block and header validation in the blockchain package has been split to help pave the way toward concurrent downloads (#386)

Misc changes:

• Minor peer optimization (#433)

Contributors (alphabetical order):

• Dave Collins
• David Hill
• Federico Bond
• Ishbir Singh
• Josh Rickmar

MSI Checksums:

SHA256(btcd_standalone_0.11.1-beta_x64.msi)= 14d5a2aaa3cbbcd37a706c9cd8918093d93f9cc826f0eed3af213c673089f126
SHA256(btcd_standalone_0.11.1-beta_x86.msi)= eb6e558a81e406d4497de1ad5ca94b12d57be62745fdcc1669b254716f5aa1c0
SHA512(btcd_standalone_0.11.1-beta_x64.msi)= 2519b2c8e2990e9cdc4ae36f236ed7544848890fd4f8b0ff4e1a7596099806feb39aa47c4e10c231c51f115daf12e4484a6a85958877589e792bb95dd2519781
SHA512(btcd_standalone_0.11.1-beta_x86.msi)= 74d52f60feef618055556a779b38f0773df8e997e1c691db6559dea28f5e0784f8f362cf3f37dc7cd91f22cc7ae9e17940955da8b81d903910e06d3f9ae8523c

Protocol and network related changes:

• IMPORTANT: Update is required due to the following point
• Correct a few corner cases in script handling which could result in forking from the network on non-standard transactions (#425)
• Add a new checkpoint at block height 352940 (#418)
• Optimized script execution (#395, #400, #404, #409)
• Fix a case that could lead stalled syncs (#138, #296)

Network address manager changes:

• Implement eclipse attack countermeasures as proposed in http://cs-people.bu.edu/heilman/eclipse (#370, #373)

Optional address indexing changes:

• Fix an issue where a reorg could cause an orderly shutdown when the address index is active (#340, #357)

Transaction relay (memory pool) changes:

• Increase maximum allowed space for nulldata transactions to 80 bytes (#331)
• Implement support for the following rules specified by BIP0062:
  • The S value in ECDSA signature must be at most half the curve order (rule 5) (#349)
  • Script execution must result in a single non-zero value on the stack (rule 6) (#347)
  • NOTE: All 7 rules of BIP0062 are now implemented
• Use network adjusted time in finalized transaction checks to improve consistency across nodes (#332)
• Process orphan transactions on acceptance of new transactions (#345)

RPC changes:

• Add support for a limited RPC user which is not allowed admin level operations on the server (#363)
• Implement node command for more unified control over connected peers (#79, #341)
• Implement generate command for regtest/simnet to support deterministically mining a specified number of blocks
  (#362, #407)
• Update searchrawtransactions to return the matching transactions in order (#354)
• Correct an issue with searchrawtransactions where it could return duplicates (#346, #354)
• Increase precision of difficulty field in getblock result to 8 (#414, #415)
• Omit nextblockhash field from getblock result when it is empty (#416, #417)
• Add id and timeoffset fields to getpeerinfo result (#335)

Websocket changes:

• Implement new commands stopnotifyspent, stopnotifyreceived, stopnotifyblocks, and stopnotifynewtransactions to allow clients to cancel notification registrations (#122, #342)

btcctl utility changes:

• A single dash can now be used as an argument to cause that argument to be read from stdin (#348)
• Add generate command

Notable developer-related package changes:

• The new version 2 btcjson package has now replaced the deprecated version 1 package (#368)
• The btcec package now performs all signing using RFC6979 deterministic signatures (#358, #360)
• The txscript package has been significantly cleaned up and had a few API changes (#387, #388, #389, #390, #391, #392, #393, #395, #396, #400, #403, #404, #405, #406, #408, #409, #410, #412)
• A new PkScriptLocs function has been added to the wire package MsgTx type which provides callers that deal with scripts optimization opportunities (#343)

Misc changes:

• Minor wire hashing optimizations (#366, #367)
• Other minor internal optimizations

Contributors (alphabetical order):

• Alex Akselrod
• Arne Brutschy
• Chris Jepson
• Daniel Krawisz
• Dave Collins
• David Hill
• Jimmy Song
• Jonas Nick
• Josh Rickmar
• Olaoluwa Osuntokun
• Oleg Andreev

MSI Checksums:

SHA256(btcd_standalone_0.11.0-beta_x64.msi)= d2023ce1243b52afc12a6c84f8d176a7b5d699ef551aafcdd248abd31b3c635d
SHA256(btcd_standalone_0.11.0-beta_x86.msi)= 22e63783cb44e909190ff91cef05c7aa4267c0d9d758aaf459bd77ef3053b810
SHA512(btcd_standalone_0.11.0-beta_x64.msi)= 8ed8e7cf65c70b5981ef58f6ff3b63beab611c9cd3b6dac70e6cb940b3788b44dcd530251de2be4410371adab224e17386aefe38bd4b031dce28ecbe2b26ea78
SHA512(btcd_standalone_0.11.0-beta_x86.msi)= 878aa38fb29ea809ab341a554ad9ab646cc7b4e260e7d09fa7eb1c10af2bb60ed23eca8d6ae9ff0f61f8ea0a54ed143523069a0b9786268482284b9537ef0307

Protocol and network related changes:

• Add a new checkpoint at block height 343185
• Implement BIP066 which includes support for version 3 blocks, a new consensus rule which prevents non-DER encoded signatures, and a double-threshold switchover mechanism
• Rather than announcing all known addresses on getaddr requests which can possibly result in multiple messages, randomize the results and limit them to the max allowed by a single message (1000 addresses)
• Add more reserved IP spaces to the address manager

Transaction relay (memory pool) changes:

• Make transactions which contain reserved opcodes nonstandard
• No longer accept or relay free and low-fee transactions that have insufficient priority to be mined in the next block
• Implement support for the following rules specified by BIP0062:
  • ECDSA signature must use strict DER encoding (rule 1)
  • The signature script must only contain push operations (rule 2)
  • All push operations must use the smallest possible encoding (rule 3)
  • All stack values interpreted as a number must be encoding using the shortest possible form (rule 4)
  • NOTE: Rule 1 was already enforced, however the entire script now evaluates to false rather than only the signature verification as required by BIP0062
• Allow transactions with nulldata transaction outputs to be treated as standard

Mining support changes:

• Modify the getblocktemplate RPC to generate and return block templates for version 3 blocks which are compatible with BIP0066
• Allow getblocktemplate to serve blocks when the current time is less than the minimum allowed time for a generated block template (#209)

Crypto changes:

• Optimize scalar multiplication by the base point by using a pre-computed table which results in approximately a 35% speedup (btcsuite/btcec#2)
• Optimize general scalar multiplication by using the secp256k1 endomorphism which results in approximately a 17-20% speedup (btcsuite/btcec#1)
• Optimize general scalar multiplication by using non-adjacent form which results in approximately an additional 8% speedup (btcsuite/btcec#3)

Implement optional address indexing:

• Add a new parameter --addrindex which will enable the creation of an address index which can be queried to determine all transactions which involve a given address (#190)
• Add a new logging subsystem for address index related operations
• Support new searchrawtransactions RPC (#185)

RPC changes:

• Require TLS version 1.2 as the minimum version for all TLS connections
• Provide support for disabling TLS when only listening on localhost (#192)
• Modify help output for all commands to provide much more consistent and detailed information
• Correct case in getrawtransaction which would refuse to serve certain transactions with invalid scripts (#210)
• Correct error handling in the getrawtransaction RPC which could lead to a crash in rare cases (#196)
• Update getinfo RPC to include the appropriate 'timeoffset' calculated from the median network time
• Modify listreceivedbyaddress result type to include txids field so it is compatible
• Add 'iswatchonly' field to validateaddress result
• Add 'startingpriority' and 'currentpriority' fields to getrawmempool (#178)
• Don't omit the 'confirmations' field from getrawtransaction when it is zero

Websocket changes:

• Modify the behavior of the rescan command to automatically register for notifications about transactions paying to rescanned addresses or spending outputs from the final rescan utxo set when the rescan is through the best block in the chain

btcctl utility changes:

• Make the list of commands available via the -l option rather than dumping the entire list on usage errors
• Alphabetize and categorize the list of commands by chain and wallet
• Make the help option only show the help options instead of also dumping all of the commands
• Make the usage syntax much more consistent and correct a few cases of misnamed fields (#305)
• Improve usage errors to show the specific parameter number, reason, and error code
• Only show the usage for specific command is shown when a valid command is provided with invalid parameters
• Add support for a SOCK5 proxy
• Modify output for integer fields (such as timestamps) to display normally instead in scientific notation
• Add invalidateblock command
• Add reconsiderblock command
• Add createnewaccount command
• Add renameaccount command
• Add searchrawtransactions command
• Add importaddress command
• Add importpubkey command

showblock utility changes:

• Remove utility in favor of the RPC getblock method

Notable developer-related package changes:

• Many of the core packages have been relocated into the btcd repository
  (#214)
• A new version of the btcjson package that has been completely redesigned from the ground up based based upon how the project has evolved and lessons learned while using it since it was first written is now available in the btcjson/v2/btcjson directory
  • This will ultimately replace the current version so anyone making use of this package will need to update their code accordingly
• The btcec package now provides better facilities for working directly with its public and private keys without having to mix elements from the ecdsa package
• Update the script builder to ensure all rules specified by BIP0062 are adhered to when creating scripts
• The blockchain package now provides a MedianTimeSource interface and concrete implementation for providing time samples from remote peers and using that data to calculate an offset against the local time

Misc changes:

• Fix a slow memory leak due to tickers not being stopped (#189)
• Fix an issue where a mix of orphans and SPV clients could trigger a condition where peers would no longer be served (#231)
• The RPC username and password can now contain symbols which previously conflicted with special symbols used in URLs
• Improve handling of obtaining random nonces to prevent cases where it could error when not enough entropy was available
• Improve handling of home directory creation errors such as in the case of unmounted symlinks (#193)
• Improve the error reporting for rejected transactions to include the inputs which are missing and/or being double spent
• Update sample config file with new options and correct a comment regarding the fact the RPC server only listens on localhost by default (#218)
• Update the continuous integration builds to run several tools which help keep code quality high
• Significant amount of internal code cleanup and improvements
• Other minor internal optimizations

Code Contributors (alphabetical order):
Beldur
Ben Holden-Crowther
Dave Collins
David Evans
David Hill
Guilherme Salgado
Javed Khan
Jimmy Song
John C. Vernaleo
Jonathan Gillham
Josh Rickmar
Michael Ford
Michail Kargakis
kac
Olaoluwa Osuntokun

Protocol and network related changes:

• Add a new checkpoint at block height 319400
• Add support for BIP0037 bloom filters (#132)
• Implement BIP0061 reject handling and hence support for protocol version 70002 (#133)
• Add testnet DNS seeds for peer discovery (testnet-seed.alexykot.me and testnet-seed.bitcoin.schildbach.de)
• Add mainnet DNS seed for peer discovery (seeds.bitcoin.open-nodes.org)
• Make multisig transactions with non-null dummy data nonstandard (#131)
• Make transactions with an excessive number of signature operations nonstandard
• Perform initial DNS lookups concurrently which allows connections more quickly
• Improve the address manager to significantly reduce memory usage and add tests
• Remove orphan transactions when they appear in a mined block (#166)
• Apply incremental back off on connection retries for persistent peers that give invalid replies to mirror the logic used for failed connections (#103)
• Correct rate-limiting of free and low-fee transactions

Mining support changes:

• Implement getblocktemplate RPC with the following support: (#124)
  • BIP0022 Non-Optional Sections
  • BIP0022 Long Polling
  • BIP0023 Basic Pool Extensions
  • BIP0023 Mutation coinbase/append
  • BIP0023 Mutations time, time/increment, and time/decrement
  • BIP0023 Mutation transactions/add
  • BIP0023 Mutations prevblock, coinbase, and generation
  • BIP0023 Block Proposals
• Implement built-in concurrent CPU miner (#137)
  • NOTE: CPU mining on mainnet is pointless as the difficulty is far too high. This has been provided for testing purposes such as for the new simulation test network
  • Add --generate flag to enable CPU mining
  • Deprecate the --getworkkey flag in favor of --miningaddr which specifies which addresses generated blocks will choose from to pay the subsidy to

RPC changes:

• Implement gettxout command (#141)
• Implement validateaddress command
• Implement verifymessage command
• Mark getunconfirmedbalance RPC as wallet-only
• Mark getwalletinfo RPC as wallet-only
• Update getgenerate, setgenerate, gethashespersec, and getmininginfo to return the appropriate information about new CPU mining status
• Modify getpeerinfo pingtime and pingwait field types to float64 so they are compatible
• Improve disconnect handling for normal HTTP clients
• Make error code returns for invalid hex more consistent

Websocket changes:

• Switch to a new more efficient websocket package (#134)
• Add rescanfinished notification
• Modify the rescanprogress notification to include block hash as well as height (#151)

btcctl utility changes:

• Accept --simnet flag which automatically selects the appropriate port and TLS certificates needed to communicate with btcd and btcwallet on the simulation test network
• Fix createrawtransaction command to send amounts denominated in BTC
• Add estimatefee command
• Add estimatepriority command
• Add getmininginfo command
• Add getnetworkinfo command
• Add gettxout command
• Add lockunspent command
• Add signrawtransaction command

addblock utility changes:

• Accept --simnet flag which automatically selects the appropriate port and TLS certificates needed to communicate with btcd and btcwallet on the simulation test network

Notable developer-related package changes:

• Provide a new bloom package in btcutil which allows creating and working with BIP0037 bloom filters
• Provide a new hdkeychain package in btcutil which allows working with BIP0032 hierarchical deterministic key chains
• Introduce a new btcnet package which houses network parameters
• Provide new simnet network (--simnet) which is useful for private simulation testing
• Enforce low S values in serialized signatures as detailed in BIP0062
• Return errors from all methods on the btcdb.Db interface (btcsuite/btcdb#5)
• Allow behavior flags to alter btcchain.ProcessBlock (btcsuite/btcchain#5)
• Provide a new SerializeSize API for blocks (btcsuite/btcwire#19)
• Several of the core packages now work with Google App Engine

Misc changes:

• Correct an issue where the database could corrupt under certain circumstances which would require a new chain download
• Slightly optimize deserialization
• Use the correct IP block for he.net
• Fix an issue where it was possible the block manager could hang on shutdown
• Update sample config file so the comments are on a separate line rather than the end of a line so they are not interpreted as settings (#135)
• Correct an issue where getdata requests were not being properly throttled which could lead to larger than necessary memory usage
• Always show help when given the help flag even when the config file contains invalid entries
• General code cleanup and minor optimizations

Code Contributors (alphabetical order):

Dale Rahn
Dave Collins
David Hill
Geert Johan
Glenn Lewis
Guilherme Salgado
Javed Khan
John C. Vernaleo
Jonathan Gillham
Josh Rickmar
Marcell Ortutay
Marco Peereboom
Michalis Kargakis
Nicola Larosa
Olaoluwa Osuntokun
Owain G. Ainsworth
Tomás Senart
Yurii Rashkovskii