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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

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1Bitcoin Core version 27.0 is now available from:
2
3  <https://bitcoincore.org/bin/bitcoin-core-27.0/>
4
5This release includes new features, various bug fixes and performance
6improvements, as well as updated translations.
7
8Please report bugs using the issue tracker at GitHub:
9
10  <https://github.com/bitcoin/bitcoin/issues>
11
12To receive security and update notifications, please subscribe to:
13
14  <https://bitcoincore.org/en/list/announcements/join/>
15
16How to Upgrade
17==============
18
19If you are running an older version, shut it down. Wait until it has completely
20shut down (which might take a few minutes in some cases), then run the
21installer (on Windows) or just copy over `/Applications/Bitcoin-Qt` (on macOS)
22or `bitcoind`/`bitcoin-qt` (on Linux).
23
24Upgrading directly from a version of Bitcoin Core that has reached its EOL is
25possible, but it might take some time if the data directory needs to be migrated. Old
26wallet versions of Bitcoin Core are generally supported.
27
28Compatibility
29==============
30
31Bitcoin Core is supported and extensively tested on operating systems
32using the Linux Kernel 3.17+, macOS 11.0+, and Windows 7 and newer. Bitcoin
33Core should also work on most other Unix-like systems but is not as
34frequently tested on them. It is not recommended to use Bitcoin Core on
35unsupported systems.
36
37Notable changes
38===============
39
40libbitcoinconsensus
41-------------------
42
43- libbitcoinconsensus is deprecated and will be removed for v28. This library has
44  existed for nearly 10 years with very little known uptake or impact. It has
45  become a maintenance burden.
46
47  The underlying functionality does not change between versions, so any users of
48  the library can continue to use the final release indefinitely, with the
49  understanding that Taproot is its final consensus update.
50
51  In the future, libbitcoinkernel will provide a much more useful API that is
52  aware of the UTXO set, and therefore be able to fully validate transactions and
53  blocks. (#29189)
54
55mempool.dat compatibility
56-------------------------
57
58- The `mempool.dat` file created by -persistmempool or the savemempool RPC will
59  be written in a new format. This new format includes the XOR'ing of transaction
60  contents to mitigate issues where external programs (such as anti-virus) attempt
61  to interpret and potentially modify the file.
62
63  This new format can not be read by previous software releases. To allow for a
64  downgrade, a temporary setting `-persistmempoolv1` has been added to fall back
65  to the legacy format. (#28207)
66
67P2P and network changes
68-----------------------
69
70- BIP324 v2 transport is now enabled by default. It remains possible to disable v2
71  by running with `-v2transport=0`. (#29347)
72- Manual connection options (`-connect`, `-addnode` and `-seednode`) will
73  now follow `-v2transport` to connect with v2 by default. They will retry with
74  v1 on failure. (#29058)
75
76- Network-adjusted time has been removed from consensus code. It is replaced
77  with (unadjusted) system time. The warning for a large median time offset
78  (70 minutes or more) is kept. This removes the implicit security assumption of
79  requiring an honest majority of outbound peers, and increases the importance
80  of the node operator ensuring their system time is (and stays) correct to not
81  fall out of consensus with the network. (#28956)
82
83Mempool Policy Changes
84----------------------
85
86- Opt-in Topologically Restricted Until Confirmation (TRUC) Transactions policy
87  (aka v3 transaction policy) is available for use on test networks when
88  `-acceptnonstdtxn=1` is set. By setting the transaction version number to 3, TRUC transactions
89  request the application of limits on spending of their unconfirmed outputs. These
90  restrictions simplify the assessment of incentive compatibility of accepting or
91  replacing TRUC transactions, thus ensuring any replacements are more profitable for
92  the node and making fee-bumping more reliable. TRUC transactions are currently
93  nonstandard and can only be used on test networks where the standardness rules are
94  relaxed or disabled (e.g. with `-acceptnonstdtxn=1`). (#28948)
95
96External Signing
97----------------
98
99- Support for external signing on Windows has been disabled. It will be re-enabled
100  once the underlying dependency (Boost Process), has been replaced with a different
101  library. (#28967)
102
103Updated RPCs
104------------
105
106- The addnode RPC now follows the `-v2transport` option (now on by default, see above) for making connections.
107  It remains possible to specify the transport type manually with the v2transport argument of addnode. (#29239)
108
109Build System
110------------
111
112- A C++20 capable compiler is now required to build Bitcoin Core. (#28349)
113- MacOS releases are configured to use the hardened runtime libraries (#29127)
114
115Wallet
116------
117
118- The CoinGrinder coin selection algorithm has been introduced to mitigate unnecessary
119  large input sets and lower transaction costs at high feerates. CoinGrinder
120  searches for the input set with minimal weight. Solutions found by
121  CoinGrinder will produce a change output. CoinGrinder is only active at
122  elevated feerates (default: 30+ sat/vB, based on `-consolidatefeerate`×3). (#27877)
123- The Branch And Bound coin selection algorithm will be disabled when the subtract fee
124  from outputs feature is used. (#28994)
125- If the birth time of a descriptor is detected to be later than the first transaction
126  involving that descriptor, the birth time will be reset to the earlier time. (#28920)
127
128Low-level changes
129=================
130
131Pruning
132-------
133
134- When pruning during initial block download, more blocks will be pruned at each
135  flush in order to speed up the syncing of such nodes. (#20827)
136
137Init
138----
139
140- Various fixes to prevent issues where subsequent instances of Bitcoin Core would
141  result in deletion of files in use by an existing instance. (#28784, #28946)
142- Improved handling of empty `settings.json` files. (#29144)
143
144Credits
145=======
146
147Thanks to everyone who directly contributed to this release:
148
149- 22388o⚡️
150- Aaron Clauson
151- Amiti Uttarwar
152- Andrew Toth
153- Anthony Towns
154- Antoine Poinsot
155- Ava Chow
156- Brandon Odiwuor
157- brunoerg
158- Chris Stewart
159- Cory Fields
160- dergoegge
161- djschnei21
162- Fabian Jahr
163- fanquake
164- furszy
165- Gloria Zhao
166- Greg Sanders
167- Hennadii Stepanov
168- Hernan Marino
169- iamcarlos94
170- ismaelsadeeq
171- Jameson Lopp
172- Jesse Barton
173- John Moffett
174- Jon Atack
175- josibake
176- jrakibi
177- Justin Dhillon
178- Kashif Smith
179- kevkevin
180- Kristaps Kaupe
181- L0la L33tz
182- Luke Dashjr
183- Lőrinc
184- marco
185- MarcoFalke
186- Mark Friedenbach
187- Marnix
188- Martin Leitner-Ankerl
189- Martin Zumsande
190- Max Edwards
191- Murch
192- muxator
193- naiyoma
194- Nikodemas Tuckus
195- ns-xvrn
196- pablomartin4btc
197- Peter Todd
198- Pieter Wuille
199- Richard Myers
200- Roman Zeyde
201- Russell Yanofsky
202- Ryan Ofsky
203- Sebastian Falbesoner
204- Sergi Delgado Segura
205- Sjors Provoost
206- stickies-v
207- stratospher
208- Supachai Kheawjuy
209- TheCharlatan
210- UdjinM6
211- Vasil Dimov
212- w0xlt
213- willcl-ark
214
215
216As well as to everyone that helped with translations on
217[Transifex](https://www.transifex.com/bitcoin/bitcoin/).
218

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

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