feat(quartz): add NIP-BC onchain zaps (kind 8333)

Implements NIP-BC onchain zap events analogous to NIP-57 lightning zap receipts but for Bitcoin transactions. The recipient's Nostr pubkey is used directly as the internal key of a BIP-341 P2TR output. Mirrors the nip88Polls package structure with a single `zap/` subpackage: - OnchainZapEvent (kind 8333) with profile / event / addressable-event zap builders - Tags: BitcoinTxIdTag (i = bitcoin:tx:<txid>), AmountTag (sats), BlockTag (hash + height), ProofTag (raw-tx + merkle proof) for optional SPV verification - TagArrayExt / TagArrayBuilderExt for parsing and assembly - EventFactory wired so kind 8333 deserializes into OnchainZapEvent Reuses standard ETag/ATag/PTag/KindTag from nip01Core. Does not yet implement client-side transaction verification or PSBT signer methods.
2026-05-14 03:25:44 +00:00
parent 17f207bb31
commit d095dc790d
8 changed files with 473 additions and 0 deletions
@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap
+
+import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip01Core.core.AddressableEvent
+import com.vitorpamplona.quartz.nip01Core.core.Event
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip01Core.core.TagArrayBuilder
+import com.vitorpamplona.quartz.nip01Core.hints.AddressHintProvider
+import com.vitorpamplona.quartz.nip01Core.hints.EventHintBundle
+import com.vitorpamplona.quartz.nip01Core.hints.EventHintProvider
+import com.vitorpamplona.quartz.nip01Core.hints.PubKeyHintProvider
+import com.vitorpamplona.quartz.nip01Core.signers.eventTemplate
+import com.vitorpamplona.quartz.nip01Core.tags.aTag.ATag
+import com.vitorpamplona.quartz.nip01Core.tags.aTag.toATag
+import com.vitorpamplona.quartz.nip01Core.tags.events.ETag
+import com.vitorpamplona.quartz.nip01Core.tags.events.toETag
+import com.vitorpamplona.quartz.nip01Core.tags.people.PTag
+import com.vitorpamplona.quartz.nip31Alts.alt
+import com.vitorpamplona.quartz.utils.TimeUtils
+
+/**
+ * NIP-BC: Onchain Zaps.
+ *
+ * Kind 8333 event that attributes a Bitcoin onchain payment to a Nostr event or profile.
+ * The recipient's Nostr pubkey is used directly as the internal key of a BIP-341 P2TR
+ * output, so every Nostr pubkey has exactly one corresponding mainnet Taproot address.
+ *
+ * Mainnet only.
+ */
+@Immutable
+class OnchainZapEvent(
+    id: HexKey,
+    pubKey: HexKey,
+    createdAt: Long,
+    tags: Array<Array<String>>,
+    content: String,
+    sig: HexKey,
+) : Event(id, pubKey, createdAt, KIND, tags, content, sig),
+    EventHintProvider,
+    AddressHintProvider,
+    PubKeyHintProvider {
+    override fun pubKeyHints() = tags.mapNotNull(PTag::parseAsHint)
+
+    override fun linkedPubKeys() = tags.mapNotNull(PTag::parseKey)
+
+    override fun eventHints() = tags.mapNotNull(ETag::parseAsHint)
+
+    override fun linkedEventIds() = tags.mapNotNull(ETag::parseId)
+
+    override fun addressHints() = tags.mapNotNull(ATag::parseAsHint)
+
+    override fun linkedAddressIds() = tags.mapNotNull(ATag::parseAddressId)
+
+    /** The Bitcoin transaction id (64-char lowercase hex) parsed from the `i` tag. */
+    fun txid() = tags.txid()
+
+    /** Sender-claimed amount in satoshis. Must be verified against the on-chain transaction. */
+    fun claimedAmountInSats() = tags.amountInSats()
+
+    /** The hex-encoded pubkey of the recipient (the author being paid). */
+    fun recipient() = tags.firstNotNullOfOrNull(PTag::parseKey)
+
+    /** The event being zapped, if any. */
+    fun zappedEvent() = tags.firstNotNullOfOrNull(ETag::parseId)
+
+    /** The addressable event being zapped, if any. */
+    fun zappedAddress() = tags.firstNotNullOfOrNull(ATag::parseAddressId)
+
+    /** Optional block tag with hash + height enabling SPV verification. */
+    fun block() = tags.block()
+
+    /** Optional inline SPV proof (raw tx hex + merkle proof hex). */
+    fun proof() = tags.proof()
+
+    /** True when neither `e` nor `a` is present — the zap targets the recipient's profile. */
+    fun isProfileZap() = zappedEvent() == null && zappedAddress() == null
+
+    companion object {
+        const val KIND = 8333
+        const val ALT_DESCRIPTION = "Onchain Zap"
+
+        /**
+         * Build an onchain zap that targets a specific event.
+         */
+        fun build(
+            txid: String,
+            recipientPubKey: HexKey,
+            amountInSats: Long,
+            zappedEvent: EventHintBundle<out Event>,
+            content: String = "",
+            createdAt: Long = TimeUtils.now(),
+            initializer: TagArrayBuilder<OnchainZapEvent>.() -> Unit = {},
+        ) = eventTemplate(KIND, content, createdAt) {
+            alt(ALT_DESCRIPTION)
+            txid(txid)
+            recipient(recipientPubKey)
+            amountInSats(amountInSats)
+            if (zappedEvent.event is AddressableEvent) {
+                zappedAddress(zappedEvent.toATag())
+            }
+            zappedEvent(zappedEvent.toETag())
+            zappedKind(zappedEvent.event.kind)
+            initializer()
+        }
+
+        /**
+         * Build an onchain zap that targets a recipient's profile (no event / address).
+         */
+        fun buildProfileZap(
+            txid: String,
+            recipientPubKey: HexKey,
+            amountInSats: Long,
+            content: String = "",
+            createdAt: Long = TimeUtils.now(),
+            initializer: TagArrayBuilder<OnchainZapEvent>.() -> Unit = {},
+        ) = eventTemplate(KIND, content, createdAt) {
+            alt(ALT_DESCRIPTION)
+            txid(txid)
+            recipient(recipientPubKey)
+            amountInSats(amountInSats)
+            initializer()
+        }
+    }
+}
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap
+
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import com.vitorpamplona.quartz.nip01Core.core.TagArrayBuilder
+import com.vitorpamplona.quartz.nip01Core.tags.aTag.ATag
+import com.vitorpamplona.quartz.nip01Core.tags.events.ETag
+import com.vitorpamplona.quartz.nip01Core.tags.kinds.KindTag
+import com.vitorpamplona.quartz.nip01Core.tags.people.PTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.AmountTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.BitcoinTxIdTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.BlockTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.ProofTag
+
+fun TagArrayBuilder<OnchainZapEvent>.txid(txid: String) = addUnique(BitcoinTxIdTag.assemble(txid))
+
+fun TagArrayBuilder<OnchainZapEvent>.recipient(recipientPubKey: HexKey) = addUnique(PTag.assemble(recipientPubKey, null))
+
+fun TagArrayBuilder<OnchainZapEvent>.amountInSats(amountInSats: Long) = addUnique(AmountTag.assemble(amountInSats))
+
+fun TagArrayBuilder<OnchainZapEvent>.zappedEvent(tag: ETag) = addUnique(tag.toTagArray())
+
+fun TagArrayBuilder<OnchainZapEvent>.zappedAddress(tag: ATag) = addUnique(tag.toATagArray())
+
+fun TagArrayBuilder<OnchainZapEvent>.zappedKind(kind: Int) = addUnique(KindTag.assemble(kind))
+
+fun TagArrayBuilder<OnchainZapEvent>.block(
+    blockHashHex: String,
+    height: Long,
+) = addUnique(BlockTag.assemble(blockHashHex, height))
+
+fun TagArrayBuilder<OnchainZapEvent>.block(block: BlockTag) = addUnique(block.toTagArray())
+
+fun TagArrayBuilder<OnchainZapEvent>.proof(
+    rawTxHex: String,
+    merkleProofHex: String,
+) = addUnique(ProofTag.assemble(rawTxHex, merkleProofHex))
+
+fun TagArrayBuilder<OnchainZapEvent>.proof(proof: ProofTag) = addUnique(proof.toTagArray())
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap
+
+import com.vitorpamplona.quartz.nip01Core.core.TagArray
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.AmountTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.BitcoinTxIdTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.BlockTag
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags.ProofTag
+
+fun TagArray.txid() = firstNotNullOfOrNull(BitcoinTxIdTag::parse)
+
+fun TagArray.amountInSats() = firstNotNullOfOrNull(AmountTag::parse)
+
+fun TagArray.block() = firstNotNullOfOrNull(BlockTag::parse)
+
+fun TagArray.proof() = firstNotNullOfOrNull(ProofTag::parse)
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags
+
+import com.vitorpamplona.quartz.nip01Core.core.has
+import com.vitorpamplona.quartz.utils.ensure
+
+class AmountTag {
+    companion object {
+        const val TAG_NAME = "amount"
+
+        fun isTag(tag: Array<String>) = tag.has(1) && tag[0] == TAG_NAME && tag[1].isNotEmpty()
+
+        fun parse(tag: Array<String>): Long? {
+            ensure(tag.has(1)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
+            return tag[1].toLongOrNull()
+        }
+
+        fun assemble(amountInSats: Long) = arrayOf(TAG_NAME, amountInSats.toString())
+    }
+}
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags
+
+import com.vitorpamplona.quartz.nip01Core.core.has
+import com.vitorpamplona.quartz.utils.Hex
+import com.vitorpamplona.quartz.utils.ensure
+
+class BitcoinTxIdTag {
+    companion object {
+        const val TAG_NAME = "i"
+        const val PREFIX = "bitcoin:tx:"
+        const val TXID_LENGTH = 64
+
+        fun isTag(tag: Array<String>) =
+            tag.has(1) &&
+                tag[0] == TAG_NAME &&
+                tag[1].startsWith(PREFIX) &&
+                tag[1].length == PREFIX.length + TXID_LENGTH
+
+        fun isTagged(
+            tag: Array<String>,
+            txid: String,
+        ) = tag.has(1) && tag[0] == TAG_NAME && tag[1] == assembleScope(txid)
+
+        fun parse(tag: Array<String>): String? {
+            ensure(tag.has(1)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].startsWith(PREFIX)) { return null }
+
+            val txid = tag[1].substring(PREFIX.length)
+            ensure(txid.length == TXID_LENGTH) { return null }
+            ensure(txid == txid.lowercase()) { return null }
+            ensure(Hex.isHex(txid)) { return null }
+
+            return txid
+        }
+
+        fun parseScope(tag: Array<String>): String? {
+            ensure(tag.has(1)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].startsWith(PREFIX)) { return null }
+            return tag[1]
+        }
+
+        fun assembleScope(txid: String) = PREFIX + txid.lowercase()
+
+        fun assemble(txid: String) = arrayOf(TAG_NAME, assembleScope(txid))
+    }
+}
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags
+
+import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip01Core.core.has
+import com.vitorpamplona.quartz.utils.Hex
+import com.vitorpamplona.quartz.utils.ensure
+
+@Immutable
+data class BlockTag(
+    val blockHashHex: String,
+    val height: Long,
+) {
+    fun toTagArray() = assemble(blockHashHex, height)
+
+    companion object {
+        const val TAG_NAME = "block"
+        const val BLOCK_HASH_LENGTH = 64
+
+        fun isTag(tag: Array<String>) =
+            tag.has(2) &&
+                tag[0] == TAG_NAME &&
+                tag[1].length == BLOCK_HASH_LENGTH &&
+                tag[2].isNotEmpty()
+
+        fun parse(tag: Array<String>): BlockTag? {
+            ensure(tag.has(2)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].length == BLOCK_HASH_LENGTH) { return null }
+            ensure(Hex.isHex(tag[1])) { return null }
+            ensure(tag[2].isNotEmpty()) { return null }
+
+            val height = tag[2].toLongOrNull() ?: return null
+            ensure(height >= 0) { return null }
+
+            return BlockTag(tag[1].lowercase(), height)
+        }
+
+        fun assemble(
+            blockHashHex: String,
+            height: Long,
+        ) = arrayOf(TAG_NAME, blockHashHex.lowercase(), height.toString())
+
+        fun assemble(block: BlockTag) = assemble(block.blockHashHex, block.height)
+    }
+}
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nipBCOnchainZaps.zap.tags
+
+import androidx.compose.runtime.Immutable
+import com.vitorpamplona.quartz.nip01Core.core.has
+import com.vitorpamplona.quartz.utils.Hex
+import com.vitorpamplona.quartz.utils.ensure
+
+@Immutable
+data class ProofTag(
+    val rawTxHex: String,
+    val merkleProofHex: String,
+) {
+    fun toTagArray() = assemble(rawTxHex, merkleProofHex)
+
+    companion object {
+        const val TAG_NAME = "proof"
+
+        fun isTag(tag: Array<String>) =
+            tag.has(2) &&
+                tag[0] == TAG_NAME &&
+                tag[1].isNotEmpty()
+
+        fun parse(tag: Array<String>): ProofTag? {
+            ensure(tag.has(2)) { return null }
+            ensure(tag[0] == TAG_NAME) { return null }
+            ensure(tag[1].isNotEmpty()) { return null }
+            ensure(Hex.isHex(tag[1])) { return null }
+            ensure(Hex.isHex(tag[2])) { return null }
+
+            return ProofTag(tag[1].lowercase(), tag[2].lowercase())
+        }
+
+        fun assemble(
+            rawTxHex: String,
+            merkleProofHex: String,
+        ) = arrayOf(TAG_NAME, rawTxHex.lowercase(), merkleProofHex.lowercase())
+
+        fun assemble(proof: ProofTag) = assemble(proof.rawTxHex, proof.merkleProofHex)
+    }
+}
@@ -286,6 +286,7 @@ import com.vitorpamplona.quartz.nipACWebRtcCalls.events.CallRenegotiateEvent
 import com.vitorpamplona.quartz.nipB0WebBookmarks.WebBookmarkEvent
 import com.vitorpamplona.quartz.nipB7Blossom.BlossomAuthorizationEvent
 import com.vitorpamplona.quartz.nipB7Blossom.BlossomServersEvent
+import com.vitorpamplona.quartz.nipBCOnchainZaps.zap.OnchainZapEvent
 import com.vitorpamplona.quartz.nipC0CodeSnippets.CodeSnippetEvent
 import com.vitorpamplona.quartz.nipC7Chats.ChatEvent

@@ -517,6 +518,7 @@ class EventFactory {
                NIP90EventPublishScheduleResponseEvent.KIND -> NIP90EventPublishScheduleResponseEvent(id, pubKey, createdAt, tags, content, sig)
                NIP90EventPowDelegationRequestEvent.KIND -> NIP90EventPowDelegationRequestEvent(id, pubKey, createdAt, tags, content, sig)
                NIP90EventPowDelegationResponseEvent.KIND -> NIP90EventPowDelegationResponseEvent(id, pubKey, createdAt, tags, content, sig)
+                OnchainZapEvent.KIND -> OnchainZapEvent(id, pubKey, createdAt, tags, content, sig)
                OtsEvent.KIND -> OtsEvent(id, pubKey, createdAt, tags, content, sig)
                PaymentTargetsEvent.KIND -> PaymentTargetsEvent(id, pubKey, createdAt, tags, content, sig)
                PeopleListEvent.KIND -> PeopleListEvent(id, pubKey, createdAt, tags, content, sig)