Remove Taproot BIP 9 deployment

Sjors commented at 11:16 am on September 29, 2022: member

Drop DEPLOYMENT_TAPROOT from consensus.vDeployments.

Now that the commit (https://github.com/bitcoin/bitcoin/commit/7c08d81e119570792648fe95bbacddbb1d5f9ae2) which changes taproot to be enforced for all blocks is included in v24.0, it seems a good time to remove no longer needed non-consensus code.

Clarify what is considered a BuriedDeployment.

We drop taproot from getdeploymentinfo RPC, rather than mark it as buried, because this is not a buried deployment in the sense of BIP 90. This is because the activation height has been completely removed from the code, unlike the hardcoded DEPLOYMENT_SEGWIT height which is still relied on.¹

See discussion in #24737 and #26162.

DEPLOYMENT_SEGWIT is used in IsBlockMutated to determine if witness data is allowed, it’s used for BIP147, to trigger NeedsRedownload() for users who upgraded after a decade, and for a few other things. ↩︎

DrahtBot commented at 2:34 pm on September 30, 2022: contributor

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/26201.

Reviews

See the guideline for information on the review process.

Type	Reviewers
ACK	ajtowns, sedited
Concept ACK	l0rinc, darosior
Approach ACK	jonatack

If your review is incorrectly listed, please copy-paste <!–meta-tag:bot-skip–> into the comment that the bot should ignore.

Conflicts

Reviewers, this pull request conflicts with the following ones:

#34677 (kernel: Chainparams and headerssync updates pre-31.0 by achow101)
#34049 (rpc: Disallow captures in RPCMethodImpl by ajtowns)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

luke-jr commented at 2:04 pm on October 2, 2022: member

Concept ~0, but I object the claim in general that commits “sufficiently buried by other commits, and thus less likely to be reverted”. Git isn’t PoW, and “burying” commits does not make them less likely to be reverted.

Sjors commented at 9:22 am on October 3, 2022: member

@luke-jr changed the wording to “is (probably) included in v24.0”.

ajtowns commented at 3:47 am on October 8, 2022: contributor

This should be updating MinBIP9WarningHeight above the taproot activation height (otherwise you should see "warnings": "Unknown new rules activated (versionbit 2)" due to miner signalling)

Sjors force-pushed on Nov 1, 2022

Sjors commented at 9:41 am on November 1, 2022: member

@ajtowns done

in src/consensus/params.h:99 in 8f96e52405 outdated

 95@@ -94,7 +96,7 @@ struct Params {
 96      * BIP 16 exception blocks. */
 97     int SegwitHeight;
 98     /** Don't warn about unknown BIP 9 activations below this height.
 99-     * This prevents us from warning about the CSV and segwit activations. */
100+     * This prevents us from warning about the CSV,segwit and taproot activations. */

maflcko commented at 9:48 am on November 1, 2022:

0     * This prevents us from warning about the CSV, segwit and taproot activations. */

nit

in doc/release-notes-26201.md:4 in 8f96e52405 outdated

0@@ -0,0 +1,5 @@
1+RPC
2+---
3+
4+- 'taproot' has been removed from 'getdeploymentinfo', rather than marked as buried,

maflcko commented at 9:49 am on November 1, 2022:

0- 'taproot' has been removed from 'getdeploymentinfo',

nit: I think release notes should describe changes, not provide extended discussion about alternatives

Sjors force-pushed on Nov 1, 2022

DrahtBot added the label Needs rebase on Mar 16, 2023

achow101 commented at 3:23 pm on April 25, 2023: member

Are you still working on this?

Sjors commented at 2:12 pm on May 8, 2023: member

I’ll rebase soon(tm).

in src/deploymentinfo.cpp:19 in 20ef70f750 outdated

10@@ -11,10 +11,6 @@ const struct VBDeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_B
11         /*.name =*/ "testdummy",
12         /*.gbt_force =*/ true,
13     },
14-    {
15-        /*.name =*/ "taproot",
16-        /*.gbt_force =*/ true,
17-    },

luke-jr commented at 0:54 am on July 27, 2023:

This will need aRules in rpc/mining.cpp updated

luke-jr changes_requested

Sjors force-pushed on Aug 18, 2023

in src/rpc/mining.cpp:866 in 7fb3287fd1 outdated

860@@ -861,7 +861,10 @@ static RPCHelpMan getblocktemplate()
861 
862     UniValue aRules(UniValue::VARR);
863     aRules.push_back("csv");
864-    if (!fPreSegWit) aRules.push_back("!segwit");
865+    if (!fPreSegWit) {
866+        aRules.push_back("!segwit");
867+        aRules.push_back("!taproot");

Sjors commented at 10:30 am on August 18, 2023:

@luke-jr like this?

This will need aRules in rpc/mining.cpp updated

Sjors commented at 10:50 am on August 18, 2023:

Oh wait, without !

I’ll push a fix and add a test…

Before and after this change it should be:

0bitcoin-cli getblocktemplate '{"rules": ["segwit"]}' | jq '.rules'
1[
2  "csv",
3  "!segwit",
4  "taproot"
5]

DrahtBot removed the label Needs rebase on Aug 18, 2023

Sjors force-pushed on Aug 18, 2023

Sjors commented at 11:12 am on August 18, 2023: member

Rebased after kernel changes. Fixed a regression in getblocktemplate’s rules result, and added a test for tit.

in src/rpc/mining.cpp:951 in b5d8ddbcb9 outdated

859@@ -860,8 +860,14 @@ static RPCHelpMan getblocktemplate()
860     result.pushKV("capabilities", aCaps);
861 
862     UniValue aRules(UniValue::VARR);
863+    // See getblocktemplate changes in BIP 9:
864+    // ! indicates a more subtle change to the block structure or generation transaction
865+    // Otherwise clients may assume the rule will not impact usage of the template as-is.
866     aRules.push_back("csv");
867-    if (!fPreSegWit) aRules.push_back("!segwit");
868+    if (!fPreSegWit) {

Sjors commented at 11:16 am on August 18, 2023:

In #27433 I propose getting rid of fPreSegWit.

maflcko commented at 8:17 am on June 19, 2025:

this was #31625, but then closed

Sjors commented at 9:12 am on June 19, 2025:

Indeed it was split out from #27433 into its own PR #31625, which after some discussion I marked up for grabs.

DrahtBot added the label CI failed on Sep 12, 2023

DrahtBot removed the label CI failed on Sep 13, 2023

DrahtBot added the label Needs rebase on Oct 9, 2023

Sjors commented at 2:41 pm on October 9, 2023: member

Rebased after #28591.

Sjors force-pushed on Oct 9, 2023

DrahtBot removed the label Needs rebase on Oct 9, 2023

in src/consensus/params.h:35 in db4344fa9c outdated

32 };
33 constexpr bool ValidDeployment(BuriedDeployment dep) { return dep <= DEPLOYMENT_SEGWIT; }
34 
35 enum DeploymentPos : uint16_t {
36     DEPLOYMENT_TESTDUMMY,
37-    DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342)

maflcko commented at 2:43 pm on October 20, 2023:

Maybe add a note here that removing an entry may require bumping MinBIP9WarningHeight?

Sjors commented at 7:38 am on October 23, 2023:

Added. IIUC the WarningBitsConditionChecker uses ComputeBlockVersion (also used by the miner), which in turn uses VersionBitsConditionChecker, which uses vDeployments to determine if a softfork is STARTED or LOCKED_IN. If so it won’t issue the warning. This logic is rather convoluted…

Sjors force-pushed on Oct 23, 2023

DrahtBot added the label CI failed on Oct 23, 2023

DrahtBot removed the label CI failed on Oct 26, 2023

barrystyle referenced this in commit 6eb671c734 on Dec 16, 2023

Sjors force-pushed on Jan 9, 2024

Sjors commented at 9:06 am on January 9, 2024: member

Rebased because #27433 needed it.

DrahtBot added the label CI failed on Jan 14, 2024

Sjors force-pushed on Feb 13, 2024

DrahtBot removed the label CI failed on Feb 13, 2024

DrahtBot added the label Needs rebase on Mar 5, 2024

Sjors force-pushed on Mar 7, 2024

Sjors commented at 10:36 am on March 7, 2024: member

Rebased due to (trivial) merge conflict after #29547.

I should also point out that Silent Payments makes use of the Taproot activation height (e.g. for a more efficient indexer), but I don’t think that’s a good reason to keep these consensus params around.

DrahtBot removed the label Needs rebase on Mar 7, 2024

Sjors force-pushed on May 30, 2024

DrahtBot added the label CI failed on May 30, 2024

DrahtBot removed the label CI failed on May 30, 2024

DrahtBot added the label CI failed on Jul 15, 2024

DrahtBot removed the label CI failed on Jul 20, 2024

DrahtBot added the label Needs rebase on Aug 5, 2024

Sjors force-pushed on Aug 12, 2024

Sjors commented at 8:38 am on August 12, 2024: member

Rebased after #30560 and #29775.

DrahtBot removed the label Needs rebase on Aug 12, 2024

DrahtBot added the label Needs rebase on Aug 22, 2024

Sjors force-pushed on Aug 26, 2024

Sjors commented at 8:42 am on August 26, 2024: member

Rebased after #30658.

DrahtBot removed the label Needs rebase on Aug 26, 2024

DrahtBot added the label CI failed on Sep 12, 2024

DrahtBot removed the label CI failed on Sep 15, 2024

Sjors force-pushed on Sep 17, 2024

Sjors commented at 7:42 am on September 17, 2024: member

#27433 needed the rebase here

Sjors commented at 8:10 am on September 18, 2024: member

Removed ~ from the description (wasn’t relevant anymore anyway), since @jonatack pointed out in #28358 that these don’t get rendered nicely in merges.

DrahtBot added the label CI failed on Oct 25, 2024

DrahtBot removed the label CI failed on Oct 25, 2024

l0rinc approved

l0rinc commented at 11:16 pm on March 4, 2025: contributor

Concept ACK

DrahtBot added the label Needs rebase on Mar 6, 2025

Sjors force-pushed on Mar 6, 2025

Sjors commented at 1:26 pm on March 6, 2025: member

Rebased after #31978.

DrahtBot removed the label Needs rebase on Mar 6, 2025

jonatack commented at 3:36 am on March 7, 2025: member

Light approach ACK 301e41985ef8cc8e3098d1d737864a5ae1f5108e

DrahtBot requested review from l0rinc on Mar 7, 2025

in src/consensus/params.h:21 in 301e41985e outdated

17@@ -18,21 +18,24 @@ namespace Consensus {
18 /**
19  * A buried deployment is one where the height of the activation has been hardcoded into
20  * the client implementation long after the consensus change has activated. See BIP 90.
21+ * Consensus changes for which the new rules enforced from genesis are not listed here.

jonatack commented at 3:37 am on March 7, 2025:

Should this be like https://github.com/bitcoin/bitcoin/pull/26201/files#diff-decae4be02fb8a47ab4557fe74a9cb853bdfa3ec0fa1b515c0a1e5de91f4ad0bR1418?

0 * Consensus changes for which the new rules are enforced from genesis are not listed here.

Sjors commented at 9:19 am on March 7, 2025:

Done

Sjors force-pushed on Mar 7, 2025

DrahtBot added the label Needs rebase on Apr 29, 2025

Sjors force-pushed on Apr 30, 2025

Sjors commented at 1:09 pm on April 30, 2025: member

Rebased after #29039.

DrahtBot removed the label Needs rebase on Apr 30, 2025

DrahtBot added the label Needs rebase on May 13, 2025

Sjors force-pushed on May 14, 2025

Sjors commented at 7:01 am on May 14, 2025: member

Trivial rebase after #32386.

DrahtBot removed the label Needs rebase on May 14, 2025

DrahtBot added the label Needs rebase on Jun 19, 2025

Sjors force-pushed on Jun 19, 2025

Sjors commented at 8:09 am on June 19, 2025: member

Rebased after #31981 for minor conflict in mining_basic.py.

in doc/bips.md:62 in f08e573a87 outdated

57@@ -58,7 +58,8 @@ BIPs that are implemented by Bitcoin Core:
58   Validation rules for Taproot (including Schnorr signatures and Tapscript
59   leaves) are implemented as of **v0.21.0** ([PR 19953](https://github.com/bitcoin/bitcoin/pull/19953)),
60   with mainnet activation as of **v0.21.1** ([PR 21377](https://github.com/bitcoin/bitcoin/pull/21377),
61-  [PR 21686](https://github.com/bitcoin/bitcoin/pull/21686)).
62+  [PR 21686](https://github.com/bitcoin/bitcoin/pull/21686)),
63+  always active as of **v24.0** ([PR 23536](https://github.com/bitcoin/bitcoin/pull/23536)).

maflcko commented at 8:18 am on June 19, 2025:

could split up this doc-only update?

Sjors commented at 9:16 am on June 19, 2025:

Done in #32776

maflcko commented at 2:54 pm on June 19, 2025:

needs rebase

DrahtBot removed the label Needs rebase on Jun 19, 2025

fanquake referenced this in commit 79afe6b7c0 on Jun 19, 2025

Sjors force-pushed on Jun 19, 2025

Sjors commented at 3:02 pm on June 19, 2025: member

Rebased after splitting the doc/bips.md changes off into #32776.

DrahtBot added the label Needs rebase on Sep 3, 2025

Remove Taproot activation height

Drop DEPLOYMENT_TAPROOT from consensus.vDeployments.

Bump MinBIP9WarningHeight.

Clarify what is considered a BuriedDeployment and
drop taproot from getdeploymentinfo RPC.

Add a test to getblocktemplate to ensure the taproot
rule is still set.

Co-Authored-By: MarcoFalke <*~=`'#}+{/-|&$^_@721217.xyz>

ec17c82846

Sjors force-pushed on Sep 3, 2025

Sjors commented at 11:32 am on September 3, 2025: member

Rebased after #33274.

DrahtBot removed the label Needs rebase on Sep 3, 2025

sedited commented at 5:03 pm on December 28, 2025: contributor

Concept ACK

Seems reasonable given that we say “Consensus changes for which the new rules are enforced from genesis are not listed here.”

sedited commented at 9:07 am on February 24, 2026: contributor

We drop taproot from getdeploymentinfo RPC, rather than mark it as buried, because this is not a buried deployment in the sense of BIP 90. This is because the activation height has been completely removed from the code, rather than hard coded.

Looking at this a bit more, how is the taproot deployment different here from the segwit deployment? AFAICT the segwit height is only used for checking the NeedsRedownload condition, and the purpose of that functionality has been questioned recently too. Can you elaborate on this in the motivation?

Sjors commented at 9:26 am on February 24, 2026: member

@sedited Consensus::DEPLOYMENT_SEGWIT is also used to determine whether a block is allowed to have witness data (IsBlockMutated) and for BIP147. I expanded the PR description.

darosior commented at 8:08 pm on February 27, 2026: member

Concept ACK.

I find it confusing that we don’t simply make it a buried deployment like we did for the past 5 soft forks. But since we always enforce it from genesis, it would probably be even more confusing (for instance setting -testactivationheight=taproot@42 wouldn’t have the intended effect).

Could you update the PR title? There is no Taproot activation height. Maybe “Remove Taproot BIP 9 deployment”?

darosior commented at 8:14 pm on February 27, 2026: member

But since we always enforce it from genesis, it would probably be even more confusing (for instance setting -testactivationheight=taproot@42 wouldn’t have the intended effect).

I guess it’s already equally confusing for -testactivationheight=segwit@42. Oh well..

Sjors renamed this:
~~Remove Taproot activation height~~
Remove Taproot BIP 9 deployment
on Feb 28, 2026

in src/consensus/params.h:31 in ec17c82846

26     DEPLOYMENT_HEIGHTINCB = std::numeric_limits<int16_t>::min(),
27     DEPLOYMENT_CLTV,
28     DEPLOYMENT_DERSIG,
29     DEPLOYMENT_CSV,
30+    // SCRIPT_VERIFY_WITNESS is enforced from genesis, but the check for downloading
31+    // missing witness data is not. BIP 147 also relies on hardcoded activation height.

ajtowns commented at 5:20 pm on February 28, 2026:

I think it might be good (not necessarily in this PR) to change VBDeploymentInfo in deploymentinfo.h/cpp to perhaps specify the SCRIPT_VERIFY flags related to a deployment, or to add a std::string with some info about the deployment (EDIT: and to report this information via getdeploymentinfo).

Sjors commented at 1:28 pm on March 2, 2026:

I indeed prefer to leave this for a followup (and as you mention, maybe not needed).

in src/rpc/blockchain.cpp:1448 in ec17c82846

1445 RPCHelpMan getdeploymentinfo()
1446 {
1447     return RPCHelpMan{"getdeploymentinfo",
1448-        "Returns an object containing various state info regarding deployments of consensus changes.",
1449+        "Returns an object containing various state info regarding deployments of consensus changes.\n"
1450+        "Consensus changes for which the new rules are enforced from genesis are not listed here.",

ajtowns commented at 5:24 pm on February 28, 2026:

Since #32998 we report "script_flags": [ .., "TAPROOT", .. ] via getdeploymentinfo for all blocks except the hardcoded exceptions. I think that’s sufficient indication that the soft-fork is still enforced even if it’s not listed in the “deployments” section anymore. Maybe this comment would be better phrased as ‘are not listed ~~here~~ in “deployments”.’ ?

Sjors commented at 5:31 pm on March 2, 2026:

Changed the wording locally, will push later.

ajtowns commented at 5:38 pm on February 28, 2026: contributor

ACK ec17c82846686cb56da0535051bb701b3c84cfea

DrahtBot requested review from darosior on Feb 28, 2026

DrahtBot requested review from jonatack on Feb 28, 2026

DrahtBot requested review from sedited on Feb 28, 2026

sedited approved

sedited commented at 12:37 pm on March 1, 2026: contributor

ACK ec17c82846686cb56da0535051bb701b3c84cfea

fanquake added this to the milestone 32.0 on Mar 2, 2026

Remove Taproot BIP 9 deployment #26201

Code Coverage & Benchmarks

Reviews

Conflicts