80f02af06b
ElectrumX versions confirmed from purple-stack/doc/configuration.md. BIP44_COIN_TYPE corrected to 0 (mainnet) / 1 (testnet) to match Bitcoin Purple Core wallet (src/wallet/scriptpubkeyman.cpp)
1056 lines
45 KiB
Markdown
1056 lines
45 KiB
Markdown
# BitcoinPurple — Technical Reference
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Parameter reference for BitcoinPurple (BTCP) node operators and developers building
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on top of the network: ElectrumX server, Electrum wallet fork, Lightning Network fork.
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All values are sourced directly from the codebase unless noted otherwise.
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---
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## Quick Reference
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The most-looked-up values, all in one place.
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| Parameter | Mainnet | Testnet | Signet | Regtest |
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|-----------|---------|---------|--------|---------|
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| P2P port | `13496` | `23496` | `33496` | `18444` |
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| RPC port | `13495` | `23495` | `33495` | `18443` |
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| ElectrumX TCP | `50001` | `60001` | — | — |
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| ElectrumX SSL | `50002` | `60002` | — | — |
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| Magic bytes | `fc991395` | `29fbc5fe` | — | `31346ac9` |
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| Bech32 / BOLT11 HRP | `btcp` | `tbtcp` | `tbtcp` | `rbtcp` |
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| P2PKH prefix | 56 (`0x38`) → `P` | 56 (`0x38`) | 56 | 56 |
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| P2SH prefix | 55 (`0x37`) → `P` | 55 (`0x37`) | 55 | 55 |
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| WIF prefix | 183 (`0xb7`) | 183 (`0xb7`) | 183 | 183 |
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| BIP32 xpub | `0488B21E` | `043587CF` | `043587CF` | `043587CF` |
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| BIP32 xprv | `0488ADE4` | `04358394` | `04358394` | `04358394` |
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| Block time | 60 s | 60 s | 60 s | instant |
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| Halving interval | 500,000 blocks | — | — | 150 blocks |
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| Monetary cap (`MAX_MONEY`) | 1,000,000 BTCP | — | — | — |
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| Genesis hash | `000003823f…c015` | `000002fdc3…d998` | `00000131aa…b403` | `6f6ffbda…e1df` |
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| LN chain_hash | `15c04ef0…0000` | `98d9f92e…0000` | — | — |
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---
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## 1. Network Identity
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| Full name | BitcoinPurple | — |
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| Ticker | BTCP | — |
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| Version | 1.1.1 | `configure.ac` |
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| Daemon binary | `bitcoinpurpled` | — |
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| Config file | `~/.bitcoinpurple/bitcoinpurple.conf` | — |
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| PoW algorithm | SHA256d (identical to Bitcoin) | — |
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| Protocol version | 70016 | `src/version.h:12` |
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| Min peer protocol | 31800 | `src/version.h:18` |
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---
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## 2. Mainnet Parameters
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### 2.1 Ports
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| Service | Port | Source |
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|---------|------|--------|
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| P2P | `13496` | `src/kernel/chainparams.cpp:116` |
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| RPC | `13495` | `src/chainparamsbase.cpp:47` |
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| Tor onion | `8334` | `src/chainparamsbase.cpp:47` |
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### 2.2 Address Encoding
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| Type | Decimal | Hex | Address prefix | Source |
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|------|---------|-----|----------------|--------|
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| P2PKH (`PUBKEY_ADDRESS`) | 56 | `0x38` | `P` | `src/kernel/chainparams.cpp:154` |
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| P2SH (`SCRIPT_ADDRESS`) | 55 | `0x37` | `P` | `src/kernel/chainparams.cpp:155` |
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| WIF secret key | 183 | `0xb7` | — | `src/kernel/chainparams.cpp:156` |
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| Bech32 HRP | — | — | `btcp1…` | `src/kernel/chainparams.cpp:160` |
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### 2.3 HD Key Version Bytes
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**BIP32 standard (xpub / xprv):**
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| Type | Bytes (hex) | Base58 prefix | Source |
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|------|-------------|---------------|--------|
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| xpub | `0488B21E` | `xpub` | `src/kernel/chainparams.cpp:157` |
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| xprv | `0488ADE4` | `xprv` | `src/kernel/chainparams.cpp:158` |
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**SLIP-0132 extended headers (all script types):**
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BTCP uses the same BIP32 root bytes as Bitcoin mainnet, so the registered
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SLIP-0132 SegWit version bytes are identical to Bitcoin mainnet. Taproot/BIP86
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does **not** have registered SLIP-0132 `trub` / `trpv` headers; use standard
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`xpub` / `xprv` plus the BIP86 derivation path or descriptors.
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```python
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XPRV_HEADERS = {
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'standard': 0x0488ade4, # xprv
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'p2wpkh-p2sh': 0x049d7878, # yprv
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'p2wsh-p2sh': 0x0295b005, # Yprv
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'p2wpkh': 0x04b2430c, # zprv
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'p2wsh': 0x02aa7a99, # Zprv
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}
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XPUB_HEADERS = {
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'standard': 0x0488b21e, # xpub
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'p2wpkh-p2sh': 0x049d7cb2, # ypub
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'p2wsh-p2sh': 0x0295b43f, # Ypub
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'p2wpkh': 0x04b24746, # zpub
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'p2wsh': 0x02aa7ed3, # Zpub
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}
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```
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### 2.4 Magic Bytes (P2P message header)
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`fc 99 13 95` — Source: `src/kernel/chainparams.cpp:112-115`
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### 2.5 Genesis Block
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| Hash (display) | `000003823fbf82ea4906cbe214617ce7a70a5da29c19ecb1d65618bcf04ec015` | `src/kernel/chainparams.cpp:144` |
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| LN chain_hash (wire, reversed bytes) | `15c04ef0bc1856d6b1ec199ca25d0aa7e77c6114e2cb0649ea82bf3f82030000` | derived |
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| Merkle root | `b5f46757618a0aa2961b23f51de039ef23a77c24decc43d600348aff051f0a05` | `src/kernel/chainparams.cpp:145` |
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| Timestamp (Unix) | `1691126832` | `src/kernel/chainparams.cpp:121` |
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| Timestamp (UTC) | `2023-08-04T05:27:12Z` | — |
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| Nonce | `1302816` (`0x13E120`) | `src/kernel/chainparams.cpp:121` |
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| nBits | `1e0ffff0` | `src/kernel/chainparams.cpp:121` |
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| Version | `1` | `src/kernel/chainparams.cpp:121` |
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| Coinbase message | `"Global transactions for everyone around the world"` | `src/kernel/chainparams.cpp:64` |
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| Coinbase pubkey | `04f26c8111029cf40de900c7075706cb58e5ed1e7f1d4911790019ee8c345eeb84060b1a09fb655c88e58ff35357ffe28678e62008f759ea260c7c37c9fae23869` | `src/kernel/chainparams.cpp:65` |
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### 2.6 Consensus & Emission
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| Block time (`nPowTargetSpacing`) | 60 seconds | `src/kernel/chainparams.cpp:88` |
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| Difficulty retarget window | 120 blocks (~2 hours) | `src/kernel/chainparams.cpp:87-88` |
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| PoW target timespan | 7200 seconds | `src/kernel/chainparams.cpp:87` |
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| PoW limit | `00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff` | `src/kernel/chainparams.cpp:86` |
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| Halving interval | 500,000 blocks | `src/kernel/chainparams.cpp:78` |
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| Initial block reward | 1 BTCP | `src/validation.cpp:1549` |
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| COIN (satoshis per BTCP) | 100,000,000 | `src/consensus/amount.h:16` |
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| MAX_MONEY validation cap | 1,000,000 BTCP | `src/consensus/amount.h:27` |
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| Coinbase maturity | 100 blocks | `src/consensus/consensus.h:19` |
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| Rule change activation threshold | 108 / 120 blocks (90%) | `src/kernel/chainparams.cpp:91` |
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**Block reward schedule** (source: `src/validation.cpp:1542-1551`):
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| Era | Block range | Reward | Era total |
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|-----|-------------|--------|-----------|
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| 0 | 0 – 499,999 | 1.00000000 BTCP | 500,000 BTCP |
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| 1 | 500,000 – 999,999 | 0.50000000 BTCP | 250,000 BTCP |
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| 2 | 1,000,000 – 1,499,999 | 0.25000000 BTCP | 125,000 BTCP |
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| 3 | 1,500,000 – 1,999,999 | 0.12500000 BTCP | 62,500 BTCP |
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| ∞ | — | — | ~1,000,000 BTCP generated subsidy |
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`MAX_MONEY` is the consensus money-range sanity cap, not a direct UTXO supply
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counter. The genesis coinbase follows the normal 1 BTCP subsidy construction,
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but like Bitcoin Core-derived chains it is not spendable from the UTXO set.
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For user-facing supply text, distinguish:
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- **Maximum generated subsidy:** asymptotically ~1,000,000 BTCP.
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- **Maximum spendable subsidy:** asymptotically ~999,999 BTCP if the genesis
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coinbase remains unspendable.
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### 2.7 Difficulty Adjustment
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BTCP keeps Bitcoin's compact target / SHA256d proof-of-work validation, but the
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retarget interval is much shorter:
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| Parameter | Mainnet value | Source |
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|-----------|---------------|--------|
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| Target spacing | 60 seconds | `src/kernel/chainparams.cpp:88` |
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| Target timespan | 7,200 seconds | `src/kernel/chainparams.cpp:87` |
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| Adjustment interval | 120 blocks | `nPowTargetTimespan / nPowTargetSpacing` |
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| Retarget boundary | every block height divisible by 120 | `src/pow.cpp:18-47` |
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| Minimum actual timespan | 1,800 seconds | `src/pow.cpp:56` |
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| Maximum actual timespan | 28,800 seconds | `src/pow.cpp:58` |
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| Max change per retarget | 4x easier or 4x harder | `src/pow.cpp:56-66` |
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| Mainnet min-difficulty blocks | disabled | `fPowAllowMinDifficultyBlocks=false` |
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| No-retarget mode | disabled | `fPowNoRetargeting=false` |
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Retarget flow for a candidate block at height `H`:
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1. If `H % 120 != 0`, the block must keep the previous block's `nBits`.
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2. If `H % 120 == 0`, take the previous 120-block window:
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`first = H - 120`, `last = H - 1`.
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3. Compute `actual_timespan = last.time - first.time`.
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4. Clamp it to `[7200 / 4, 7200 * 4]`, i.e. `[1800, 28800]` seconds.
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5. Decode previous `nBits` to a target, then:
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```text
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new_target = old_target * actual_timespan / 7200
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new_target = min(new_target, powLimit)
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new_nBits = compact(new_target)
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```
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Interpretation:
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- Blocks faster than 60 seconds make `actual_timespan < 7200`, so target
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decreases and difficulty increases.
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- Blocks slower than 60 seconds make `actual_timespan > 7200`, so target
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increases and difficulty decreases.
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- The clamp prevents a single retarget from changing difficulty by more than 4x.
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### 2.8 Soft-Fork Activation
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All soft-forks are active from genesis (height 0). Source: `src/kernel/chainparams.cpp:79-102`
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| BIP | Feature | Activation height |
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|-----|---------|-------------------|
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| BIP34 | Block height in coinbase | 0 |
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| BIP65 | `CHECKLOCKTIMEVERIFY` | 0 |
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| BIP66 | Strict DER signatures | 0 |
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| BIP68/112/113 | `CheckSequenceVerify` (CSV) | 0 |
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| BIP141/143/147 | SegWit | 0 |
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| BIP340-342 | Taproot (`ALWAYS_ACTIVE`) | 0 |
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### 2.9 Chain Validation
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| Minimum chain work | `00000000000000000000000000000000000000000000074e7000dc41ac550926` | `src/kernel/chainparams.cpp:104` |
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| Default assume valid | `00000000000009733cf805e87e19261ae833319b874c694d4d74995ea526c968` | `src/kernel/chainparams.cpp:105` |
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| Prune after height | 100,000 | `src/kernel/chainparams.cpp:117` |
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| TX count reference | 1,189,400 at block 1,048,808 | `src/kernel/chainparams.cpp:178-184` |
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### 2.10 DNS Seeds
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| Seed | Source |
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|------|--------|
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| `node3.walletbuilders.com` | `src/kernel/chainparams.cpp:152` |
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---
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## 3. Testnet Parameters
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| P2P port | `23496` | `src/kernel/chainparams.cpp:230` |
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| RPC port | `23495` | `src/chainparamsbase.cpp:49` |
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| Magic bytes | `29 fb c5 fe` | `src/kernel/chainparams.cpp:226-229` |
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| Bech32 / BOLT11 HRP | `tbtcp` | `src/kernel/chainparams.cpp:270` |
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| P2PKH | 56 (`0x38`) | `src/kernel/chainparams.cpp:264` |
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| P2SH | 55 (`0x37`) | `src/kernel/chainparams.cpp:265` |
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| WIF prefix | 183 (`0xb7`) | `src/kernel/chainparams.cpp:266` |
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| BIP32 xpub | `043587CF` | `src/kernel/chainparams.cpp:267` |
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| BIP32 xprv | `04358394` | `src/kernel/chainparams.cpp:268` |
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| Genesis hash (display) | `000002fdc3921c1ad368816fcc587f499698d42b42ab5a5d94ee67882ef9d998` | `src/kernel/chainparams.cpp:259` |
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| LN chain_hash (wire) | `98d9f92e8867ee945d5aab422bd49896497f58cc6f8168d31a1c92c3fd020000` | derived |
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| Genesis merkle root | `b5f46757618a0aa2961b23f51de039ef23a77c24decc43d600348aff051f0a05` | same as mainnet |
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| Genesis timestamp | `1691126837` | `src/kernel/chainparams.cpp:235` |
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| Genesis nonce | `521609` (`0x7F589`) | `src/kernel/chainparams.cpp:235` |
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| Genesis nBits | `1e0ffff0` | `src/kernel/chainparams.cpp:235` |
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| ElectrumX TCP / SSL | `60001` / `60002` | `coins_btcp.py` |
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**SLIP-0132 HD headers — testnet** (identical to Bitcoin testnet, since BIP32 bytes are `043587CF`/`04358394`; Taproot/BIP86 still uses standard `tpub` / `tprv` plus path/descriptor metadata):
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```python
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XPRV_HEADERS = {
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'standard': 0x04358394, # tprv
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'p2wpkh-p2sh': 0x044a4e28, # uprv
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'p2wsh-p2sh': 0x024285b5, # Uprv
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'p2wpkh': 0x045f18bc, # vprv
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'p2wsh': 0x02575048, # Vprv
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}
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XPUB_HEADERS = {
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'standard': 0x043587cf, # tpub
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'p2wpkh-p2sh': 0x044a5262, # upub
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'p2wsh-p2sh': 0x024289ef, # Upub
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'p2wpkh': 0x045f1cf6, # vpub
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'p2wsh': 0x02575483, # Vpub
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}
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```
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---
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## 4. Signet Parameters
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| P2P port | `33496` | `src/kernel/chainparams.cpp:375` |
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| RPC port | `33495` | `src/chainparamsbase.cpp:51` |
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| Bech32 HRP | `tbtcp` | `src/kernel/chainparams.cpp:412` |
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| P2PKH / P2SH / WIF | 56 / 55 / 183 | `src/kernel/chainparams.cpp:406-408` |
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| BIP32 xpub / xprv | `043587CF` / `04358394` | `src/kernel/chainparams.cpp:409-410` |
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| Genesis hash | `00000131aa3124412b7ba8473f137922692c88da8fe26042e250c6cd76b7b403` | `src/kernel/chainparams.cpp:402` |
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| Genesis timestamp | `1691126842` | `src/kernel/chainparams.cpp:378` |
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| Genesis nonce | `1829993` (`0x1be0a9`) | `src/kernel/chainparams.cpp:378` |
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| Genesis nBits | `1e0377ae` | `src/kernel/chainparams.cpp:378` |
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| PoW limit | `00000377ae000000000000000000000000000000000000000000000000000000` | `src/kernel/chainparams.cpp:350` |
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| Default signet challenge | `512103ad5e0edad18cb1f0fc0d28a3d4f1f3e445640337489abb10404f2d1e086be430210359ef5021964fe22d6f8e05b2463c9540ce96883fe3b278760f048f5189f2e6c452ae` | `src/kernel/chainparams.cpp:308` |
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---
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## 5. Regtest Parameters
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| Parameter | Value | Source |
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|-----------|-------|--------|
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| P2P port | `18444` | `src/kernel/chainparams.cpp:466` |
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| RPC port | `18443` | `src/chainparamsbase.cpp:53` |
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| Magic bytes | `31 34 6a c9` | `src/kernel/chainparams.cpp:462-465` |
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| Bech32 HRP | `rbtcp` | `src/kernel/chainparams.cpp:556` |
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| P2PKH / P2SH / WIF | 56 / 55 / 183 | `src/kernel/chainparams.cpp:550-552` |
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| BIP32 xpub / xprv | `043587CF` / `04358394` | `src/kernel/chainparams.cpp:553-554` |
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| Genesis hash | `6f6ffbda4cb789c69d885d4624ea4a28841d3689fbaf969262150ca45a1ae1df` | `src/kernel/chainparams.cpp:521` |
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| Genesis timestamp | `1691126837` | `src/kernel/chainparams.cpp:497` |
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| Genesis nonce | `4` | `src/kernel/chainparams.cpp:497` |
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| Genesis nBits | `207fffff` | `src/kernel/chainparams.cpp:497` |
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| Halving interval | 150 blocks | `src/kernel/chainparams.cpp:433` |
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| No retargeting | `true` | `src/kernel/chainparams.cpp:440` |
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---
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## 6. ElectrumX Server
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| Component | Version |
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|-----------|---------|
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| ElectrumX (`e-x`) | **1.18.0** — [spesmilo/electrumx](https://github.com/spesmilo/electrumx) |
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| Python (container) | **3.13.5** |
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| Base Docker image | `lukechilds/electrumx:latest` (unpinned) |
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### 6.1 Coin Definition (`coins_btcp.py`)
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Drop-in patch for `electrumx/lib/coins.py`. Place as
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`electrumx-patch/coins_btcp.py` and apply via the Docker patch snippet below.
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```python
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# coins_btcp.py — BitcoinPurple (BTCP) coin definitions for ElectrumX
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# Patch into electrumx/lib/coins.py alongside the Bitcoin class.
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class BitcoinPurple(Bitcoin):
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NAME = 'BitcoinPurple'
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SHORTNAME = 'BTCP'
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NET = 'mainnet'
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DESERIALIZER = lib_tx.DeserializerSegWit
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GENESIS_HASH = (
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'000003823fbf82ea4906cbe214617ce7a70a5da29c19ecb1d65618bcf04ec015'
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)
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# Base58 address prefixes
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P2PKH_VERBYTE = bytes([56]) # 0x38
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P2SH_VERBYTES = (bytes([55]),) # 0x37
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WIF_BYTE = bytes([183]) # 0xb7
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# BIP32 HD key version bytes
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XPUB_VERBYTES = bytes.fromhex('0488B21E')
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XPRV_VERBYTES = bytes.fromhex('0488ADE4')
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# Bech32 / SegWit metadata for forks; ElectrumX indexes scripts directly.
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SEGWIT_HRP = 'btcp'
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# Do not inherit Bitcoin Electrum peers or Bitcoin Core version gates.
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PEERS = []
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MIN_REQUIRED_DAEMON_VERSION = '1.1.1'
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BLACKLIST_URL = None
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# 1-minute blocks: keep enough undo data for practical reorg handling.
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REORG_LIMIT = 1200
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# Chain stats — updated from fully synced mainnet node at block 1,048,808 (Apr 2026)
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TX_COUNT = 1_189_400
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TX_COUNT_HEIGHT = 1_048_808
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TX_PER_BLOCK = 2
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# RPC port (bitcoinpurpled mainnet default)
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RPC_PORT = 13495
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PEER_DEFAULT_PORTS = {'t': '50001', 's': '50002'}
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|
||
class BitcoinPurpleTestnet(BitcoinPurple):
|
||
NAME = 'BitcoinPurple Testnet'
|
||
SHORTNAME = 'TBTCP'
|
||
NET = 'testnet'
|
||
GENESIS_HASH = (
|
||
'000002fdc3921c1ad368816fcc587f499698d42b42ab5a5d94ee67882ef9d998'
|
||
)
|
||
XPUB_VERBYTES = bytes.fromhex('043587CF')
|
||
XPRV_VERBYTES = bytes.fromhex('04358394')
|
||
SEGWIT_HRP = 'tbtcp'
|
||
TX_COUNT = 1
|
||
TX_COUNT_HEIGHT = 0
|
||
TX_PER_BLOCK = 1
|
||
RPC_PORT = 23495
|
||
PEERS = []
|
||
REORG_LIMIT = 1200
|
||
PEER_DEFAULT_PORTS = {'t': '60001', 's': '60002'}
|
||
```
|
||
|
||
Notes for this coin class:
|
||
|
||
- `PEERS = []` is intentional until there are known-good BTCP ElectrumX peers.
|
||
ElectrumX peer discovery verifies genesis, but inheriting Bitcoin peers wastes
|
||
resources and can leak confusing peer data.
|
||
- `MIN_REQUIRED_DAEMON_VERSION` must not inherit Bitcoin's current upstream
|
||
requirement. Keep it aligned with the BTCP daemon version you ship, or remove
|
||
the version gate in your ElectrumX fork.
|
||
- `TX_COUNT`, `TX_COUNT_HEIGHT`, and `TX_PER_BLOCK` are sync-estimation hints,
|
||
not consensus values. Refresh them from a synced BTCP node before release.
|
||
- ElectrumX does not need ZMQ to index; it polls RPC. ZMQ is useful for lower
|
||
latency only if your chosen ElectrumX build/plugin uses it.
|
||
|
||
### 6.1.1 ElectrumX Node Requirements
|
||
|
||
Required full-node settings:
|
||
|
||
| Requirement | Value / setting | Reason |
|
||
|-------------|-----------------|--------|
|
||
| RPC server | `server=1`, `rpcport=13495` | ElectrumX reads blocks and transactions through JSON-RPC |
|
||
| Transaction index | `txindex=1` | Required for historical transaction lookups |
|
||
| Pruning | disabled (`prune=0`) | ElectrumX must be able to index from genesis |
|
||
| Chain | mainnet unless `NET=testnet` | Must match `COIN`/`NET` in ElectrumX |
|
||
| Disk | full block data + ElectrumX DB | DB grows with history; do not run from a tiny volume |
|
||
|
||
Minimum RPC methods used by ElectrumX-compatible servers include
|
||
`getblockhash`, `getblock`, `getrawtransaction`, `getnetworkinfo`,
|
||
`getblockchaininfo`, `estimatesmartfee`, and `sendrawtransaction`.
|
||
|
||
Recommended public Electrum services:
|
||
|
||
| Service | Mainnet | Testnet | Notes |
|
||
|---------|---------|---------|-------|
|
||
| Plain TCP | `50001` | `60001` | Standard Electrum convention |
|
||
| TLS/SSL TCP | `50002` | `60002` | Recommended for public wallets |
|
||
| Local admin RPC | `8000` | `8000` or private | Keep firewalled; do not advertise publicly |
|
||
|
||
For `servers.json`, replace `your-server.example.com` with a real DNS name or
|
||
public IP. The current file only documents the format; it does not configure a
|
||
real public server.
|
||
|
||
### 6.2 Docker Patch Snippet
|
||
|
||
```dockerfile
|
||
COPY electrumx-patch/coins_btcp.py /tmp/coins_btcp.py
|
||
|
||
RUN python3 - <<'PATCH'
|
||
import pathlib, re
|
||
|
||
patch = pathlib.Path('/tmp/coins_btcp.py').read_text()
|
||
classes = re.split(r'^(?=class )', patch, flags=re.MULTILINE)
|
||
classes = [c for c in classes if c.strip().startswith('class ')]
|
||
body = '\n' + '\n'.join(classes)
|
||
|
||
for target in [
|
||
'/usr/local/lib/python3.13/dist-packages/electrumx/lib/coins.py',
|
||
'/electrumx/src/electrumx/lib/coins.py',
|
||
]:
|
||
p = pathlib.Path(target)
|
||
if p.exists():
|
||
s = p.read_text()
|
||
if 'class BitcoinPurple(Bitcoin):' not in s:
|
||
p.write_text(s + body)
|
||
|
||
print('>> Patched ElectrumX with BitcoinPurple coin classes')
|
||
PATCH
|
||
```
|
||
|
||
### 6.3 Environment Variables
|
||
|
||
```env
|
||
# ── Identity ──────────────────────────────────────────────────────────────────
|
||
COIN=BitcoinPurple
|
||
NET=mainnet # or: testnet
|
||
|
||
# ── Node connection ───────────────────────────────────────────────────────────
|
||
DAEMON_URL=http://btcpuser:CHANGE_ME@bitcoinpurpled:13495/
|
||
# testnet: DAEMON_URL=http://btcpuser:CHANGE_ME@bitcoinpurpled:23495/
|
||
|
||
# ── Storage ───────────────────────────────────────────────────────────────────
|
||
DB_DIRECTORY=/data/electrumx
|
||
|
||
# ── Services exposed ──────────────────────────────────────────────────────────
|
||
SERVICES=tcp://0.0.0.0:50001,ssl://0.0.0.0:50002,rpc://0.0.0.0:8000
|
||
# Override only if auto-detected public IP is wrong:
|
||
# REPORT_SERVICES=tcp://your-server-ip:50001,ssl://your-server-ip:50002
|
||
|
||
# ── TLS ───────────────────────────────────────────────────────────────────────
|
||
SSL_CERTFILE=/certs/server.crt
|
||
SSL_KEYFILE=/certs/server.key
|
||
|
||
# ── Performance ───────────────────────────────────────────────────────────────
|
||
CACHE_MB=1200
|
||
MAX_SESSIONS=1000
|
||
INITIAL_CONCURRENT=2
|
||
|
||
# ── Rate limiting (0 = disabled) ─────────────────────────────────────────────
|
||
COST_SOFT_LIMIT=0
|
||
COST_HARD_LIMIT=0
|
||
|
||
# ── Peer discovery ────────────────────────────────────────────────────────────
|
||
PEER_DISCOVERY=on
|
||
PEER_ANNOUNCE=true
|
||
```
|
||
|
||
**Protocol version** served: `1.4.2`
|
||
|
||
**OS ulimit** — set `nofile` to at least `1048576` (open file descriptors):
|
||
|
||
```yaml
|
||
ulimits:
|
||
nofile:
|
||
soft: 1048576
|
||
hard: 1048576
|
||
```
|
||
|
||
### 6.4 ZMQ Notification Ports
|
||
|
||
These are recommended local ports if you enable ZMQ notifications. BitcoinPurple
|
||
Core does not assign default ZMQ bind ports; the port only exists if you set the
|
||
corresponding `bitcoinpurple.conf` value.
|
||
|
||
| `bitcoinpurple.conf` key | Recommended local port | Payload |
|
||
|--------------------------|------------------------|---------|
|
||
| `zmqpubrawblock` | `28332` | full serialised block |
|
||
| `zmqpubrawtx` | `28333` | raw transaction (mempool + confirmed) |
|
||
| `zmqpubhashblock` | `28334` | 32-byte block hash |
|
||
| `zmqpubhashtx` | `28335` | 32-byte tx hash |
|
||
|
||
Prevent dropped messages under load:
|
||
|
||
```ini
|
||
zmqpubrawblockhwm=500
|
||
zmqpubrawtxhwm=500
|
||
```
|
||
|
||
---
|
||
|
||
## 7. Electrum Wallet (`constants.py`)
|
||
|
||
Reference for building an Electrum wallet fork targeting BTCP.
|
||
Modelled after the `AbstractNet` interface (see `pallectrum` for a working example).
|
||
|
||
### 7.1 Parameter Table
|
||
|
||
| Field | Mainnet | Testnet | Source / Note |
|
||
|-------|---------|---------|---------------|
|
||
| `NET_NAME` | `"bitcoinpurple"` | `"testnet"` | wallet data subfolder |
|
||
| `TESTNET` | `False` | `True` | |
|
||
| `WIF_PREFIX` | `0xb7` (183) | `0xb7` (183) | same on both — `chainparams.cpp:156/266` |
|
||
| `ADDRTYPE_P2PKH` | `56` | `56` | addresses start with `P` |
|
||
| `ADDRTYPE_P2SH` | `55` | `55` | addresses start with `P` |
|
||
| `SEGWIT_HRP` | `"btcp"` | `"tbtcp"` | Bech32 human-readable part |
|
||
| `BOLT11_HRP` | `"btcp"` | `"tbtcp"` | LN invoice prefix |
|
||
| `GENESIS` | `000003823f…c015` | `000002fdc3…d998` | full hashes in §2.5 / §3 |
|
||
| `DEFAULT_PORTS` | `{'t':'50001','s':'50002'}` | `{'t':'60001','s':'60002'}` | |
|
||
| `BIP44_COIN_TYPE` | `0` | `1` | il core usa `0` (Bitcoin) in mainnet e `1` in testnet/regtest — vedere nota |
|
||
| `LN_REALM_BYTE` | `0` | `1` | LN DNS realm byte; unused while `LN_DNS_SEEDS=[]` |
|
||
| `LN_DNS_SEEDS` | `[]` | `[]` | no LN seeds configured |
|
||
| `SKIP_POW_DIFFICULTY_VALIDATION` | `False` only after BTCP retarget support | `False` only after BTCP retarget support | see §7.7 |
|
||
| `POW_TARGET_SPACING` | `60` | `60` | seconds per block |
|
||
| `COINBASE_MATURITY` | `100` | `100` | blocks before coinbase is spendable |
|
||
| `BLOCK_HEIGHT_FIRST_LIGHTNING_CHANNELS` | `0` | `0` | allowed from genesis if LN is enabled |
|
||
|
||
> **BIP44 coin type:** The Bitcoin Purple Core wallet (`src/wallet/scriptpubkeyman.cpp`)
|
||
> uses `coin_type = 0` on mainnet and `coin_type = 1` on testnet/regtest — the same
|
||
> values as Bitcoin. The resulting mainnet derivation paths are `m/44'/0'/0'/0/*`
|
||
> (BIP44 P2PKH), `m/49'/0'/0'/0/*` (BIP49 P2WPKH-P2SH), `m/84'/0'/0'/0/*`
|
||
> (BIP84 P2WPKH), and `m/86'/0'/0'/0/*` (BIP86 P2TR). BitcoinPurple has no
|
||
> registered SLIP-0044 entry; index `183` is already assigned to Bitcoin Private.
|
||
> Until an official coin type is registered, any Electrum or LND fork targeting
|
||
> BTCP should use `coin_type = 0` for mainnet and `1` for testnet to stay
|
||
> consistent with the core wallet.
|
||
|
||
### 7.2 `constants.py` Class Definitions
|
||
|
||
```python
|
||
# constants.py — BitcoinPurple network definitions for an Electrum wallet fork
|
||
# Drop these classes into electrum/constants.py alongside BitcoinMainnet.
|
||
|
||
|
||
class BitcoinPurple(AbstractNet):
|
||
|
||
NET_NAME = "bitcoinpurple"
|
||
TESTNET = False
|
||
|
||
# Address & key encoding
|
||
WIF_PREFIX = 0xb7 # 183 — chainparams.cpp:156
|
||
ADDRTYPE_P2PKH = 56 # 0x38 — chainparams.cpp:154
|
||
ADDRTYPE_P2SH = 55 # 0x37 — chainparams.cpp:155
|
||
SEGWIT_HRP = "btcp" # chainparams.cpp:160
|
||
BOLT11_HRP = SEGWIT_HRP
|
||
|
||
GENESIS = "000003823fbf82ea4906cbe214617ce7a70a5da29c19ecb1d65618bcf04ec015"
|
||
DEFAULT_PORTS = {'t': '50001', 's': '50002'}
|
||
|
||
# Consensus
|
||
COINBASE_MATURITY = 100 # consensus/consensus.h:19
|
||
POW_TARGET_SPACING = 60 # 60-second blocks
|
||
|
||
# BIP44 coin type — matches Bitcoin Purple Core (src/wallet/scriptpubkeyman.cpp)
|
||
BIP44_COIN_TYPE = 0 # same as Bitcoin mainnet; no SLIP-0044 entry registered
|
||
|
||
# Lightning. Height 0 means "allowed from genesis" in Electrum.
|
||
BLOCK_HEIGHT_FIRST_LIGHTNING_CHANNELS = 0
|
||
LN_REALM_BYTE = 0
|
||
LN_DNS_SEEDS = []
|
||
|
||
# PoW validation — requires BTCP's 120-block retarget implementation.
|
||
SKIP_POW_DIFFICULTY_VALIDATION = False
|
||
|
||
# SLIP-0132 HD key version bytes — identical to Bitcoin mainnet
|
||
# BTCP mainnet uses the same BIP32 root bytes: 0488B21E / 0488ADE4
|
||
XPRV_HEADERS = {
|
||
'standard': 0x0488ade4, # xprv
|
||
'p2wpkh-p2sh': 0x049d7878, # yprv
|
||
'p2wsh-p2sh': 0x0295b005, # Yprv
|
||
'p2wpkh': 0x04b2430c, # zprv
|
||
'p2wsh': 0x02aa7a99, # Zprv
|
||
}
|
||
XPRV_HEADERS_INV = inv_dict(XPRV_HEADERS)
|
||
XPUB_HEADERS = {
|
||
'standard': 0x0488b21e, # xpub
|
||
'p2wpkh-p2sh': 0x049d7cb2, # ypub
|
||
'p2wsh-p2sh': 0x0295b43f, # Ypub
|
||
'p2wpkh': 0x04b24746, # zpub
|
||
'p2wsh': 0x02aa7ed3, # Zpub
|
||
}
|
||
XPUB_HEADERS_INV = inv_dict(XPUB_HEADERS)
|
||
|
||
|
||
class BitcoinPurpleTestnet(BitcoinPurple):
|
||
|
||
NET_NAME = "testnet"
|
||
TESTNET = True
|
||
|
||
# Testnet uses the same address/WIF prefixes as mainnet (see chainparams)
|
||
WIF_PREFIX = 0xb7 # chainparams.cpp:266
|
||
ADDRTYPE_P2PKH = 56 # chainparams.cpp:264
|
||
ADDRTYPE_P2SH = 55 # chainparams.cpp:265
|
||
SEGWIT_HRP = "tbtcp" # chainparams.cpp:270
|
||
BOLT11_HRP = SEGWIT_HRP
|
||
|
||
GENESIS = "000002fdc3921c1ad368816fcc587f499698d42b42ab5a5d94ee67882ef9d998"
|
||
DEFAULT_PORTS = {'t': '60001', 's': '60002'}
|
||
BIP44_COIN_TYPE = 1 # standard testnet coin type
|
||
LN_REALM_BYTE = 1
|
||
|
||
# SLIP-0132 — standard Bitcoin testnet values (BIP32 root: 043587CF / 04358394)
|
||
XPRV_HEADERS = {
|
||
'standard': 0x04358394, # tprv
|
||
'p2wpkh-p2sh': 0x044a4e28, # uprv
|
||
'p2wsh-p2sh': 0x024285b5, # Uprv
|
||
'p2wpkh': 0x045f18bc, # vprv
|
||
'p2wsh': 0x02575048, # Vprv
|
||
}
|
||
XPRV_HEADERS_INV = inv_dict(XPRV_HEADERS)
|
||
XPUB_HEADERS = {
|
||
'standard': 0x043587cf, # tpub
|
||
'p2wpkh-p2sh': 0x044a5262, # upub
|
||
'p2wsh-p2sh': 0x024289ef, # Upub
|
||
'p2wpkh': 0x045f1cf6, # vpub
|
||
'p2wsh': 0x02575483, # Vpub
|
||
}
|
||
XPUB_HEADERS_INV = inv_dict(XPUB_HEADERS)
|
||
```
|
||
|
||
### 7.3 Derivation Paths (BIP44 / 49 / 84 / 86)
|
||
|
||
Standard HD paths for each script type. The Bitcoin Purple Core wallet uses
|
||
`COIN_TYPE = 0` on mainnet and `1` on testnet/regtest (see §7.1 note).
|
||
|
||
| BIP | Script type | Path template | xpub/xprv prefix |
|
||
|-----|-------------|---------------|-----------------|
|
||
| BIP44 | P2PKH (legacy) | `m/44'/COIN_TYPE'/0'/0/n` | `xpub` / `xprv` |
|
||
| BIP49 | P2WPKH-P2SH (wrapped SegWit) | `m/49'/COIN_TYPE'/0'/0/n` | `ypub` / `yprv` |
|
||
| BIP84 | P2WPKH (native SegWit) | `m/84'/COIN_TYPE'/0'/0/n` | `zpub` / `zprv` |
|
||
| BIP86 | P2TR (Taproot) | `m/86'/COIN_TYPE'/0'/0/n` | `xpub` / `xprv` or descriptors |
|
||
|
||
- `ACCOUNT` = `0'` (first account, hardened)
|
||
- `CHANGE` = `0` (receive) or `1` (change)
|
||
- `INDEX` = address index (unhardened)
|
||
|
||
### 7.4 Checkpoints (`checkpoints.json`)
|
||
|
||
Electrum uses checkpoints for SPV header chain verification.
|
||
The file lives at `electrum/chains/bitcoinpurple/checkpoints.json`.
|
||
|
||
Format: a JSON array of `[header_hash_hex, accumulated_work_int]` pairs,
|
||
one entry per 2016-block chunk. Chunk `n` covers blocks `n*2016` to `(n+1)*2016-1`.
|
||
|
||
```json
|
||
[
|
||
[
|
||
"000003823fbf82ea4906cbe214617ce7a70a5da29c19ecb1d65618bcf04ec015",
|
||
1048592
|
||
]
|
||
]
|
||
```
|
||
|
||
The first entry (chunk 0) is the genesis block hash with its accumulated PoW work
|
||
(`0x00000000000000000000000000000000000000000000074e7000dc41ac550926` — from `nMinimumChainWork` in chainparams.cpp:104, updated at block 1,048,808).
|
||
|
||
**To generate a full checkpoints.json** from a running node:
|
||
|
||
```python
|
||
import json, subprocess, math
|
||
|
||
def get_header(height):
|
||
h = subprocess.check_output(
|
||
['bitcoinpurple-cli', 'getblockhash', str(height)]).decode().strip()
|
||
return subprocess.check_output(
|
||
['bitcoinpurple-cli', 'getblockheader', h, 'true']).decode()
|
||
|
||
checkpoints = []
|
||
tip = int(subprocess.check_output(
|
||
['bitcoinpurple-cli', 'getblockcount']).decode().strip())
|
||
|
||
for chunk in range(tip // 2016 + 1):
|
||
height = chunk * 2016
|
||
import json as _j
|
||
header = _j.loads(get_header(height))
|
||
checkpoints.append([header['hash'], int(header['chainwork'], 16)])
|
||
|
||
print(json.dumps(checkpoints, indent=2))
|
||
```
|
||
|
||
### 7.5 `servers.json` Format
|
||
|
||
Place at `electrum/chains/bitcoinpurple/servers.json` (mainnet)
|
||
and `electrum/chains/testnet/servers.json` (testnet).
|
||
|
||
```json
|
||
{
|
||
"your-server.example.com": {
|
||
"pruning": "-",
|
||
"s": "50002",
|
||
"t": "50001",
|
||
"version": "1.4.2"
|
||
}
|
||
}
|
||
```
|
||
|
||
| Field | Meaning |
|
||
|-------|---------|
|
||
| key | hostname or IP of the ElectrumX server |
|
||
| `"pruning"` | `"-"` = full node; a number = pruned at that height |
|
||
| `"s"` | SSL port |
|
||
| `"t"` | TCP plain port |
|
||
| `"version"` | minimum Electrum protocol version required |
|
||
|
||
### 7.6 Dust Thresholds
|
||
|
||
Minimum output values below which an output is considered "dust" and non-standard.
|
||
These are the same as Bitcoin since BTCP uses identical script formats.
|
||
|
||
| Script type | Dust limit | Policy fee rate |
|
||
|-------------|-----------|-----------------|
|
||
| P2PKH | 546 sat | `DUST_RELAY_TX_FEE` = 3000 sat/kvB (`src/policy/policy.h:55`) |
|
||
| P2WPKH (native SegWit) | 294 sat | same |
|
||
| P2WSH | 330 sat | same |
|
||
| P2TR (Taproot) | 294 sat | same |
|
||
| `OP_RETURN` | 0 (unspendable) | max 83 bytes (`src/script/standard.h:34`) |
|
||
|
||
### 7.7 Electrum Header Verification
|
||
|
||
Do not reuse Bitcoin's 2016-block difficulty verification logic unchanged.
|
||
BTCP uses Bitcoin-style compact targets and double-SHA256 proof-of-work, but
|
||
retargets every 120 blocks with a 7,200 second target timespan.
|
||
|
||
Wallet constants / chain-verifier values:
|
||
|
||
```python
|
||
POW_LIMIT = int(
|
||
"00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", 16
|
||
)
|
||
TARGET_SPACING = 60
|
||
TARGET_TIMESPAN = 120 * 60
|
||
DIFFICULTY_ADJUSTMENT_INTERVAL = 120
|
||
MAX_ADJUSTMENT_FACTOR = 4
|
||
```
|
||
|
||
Header validation must perform:
|
||
|
||
1. Verify `double_sha256(header) <= target_from_nbits(header.bits)`.
|
||
2. Verify target is `> 0` and `<= POW_LIMIT`.
|
||
3. If `height % 120 != 0`, require `header.bits == previous.bits`.
|
||
4. If `height % 120 == 0`, compute expected `bits` from the previous 120-block
|
||
window using the §2.7 formula.
|
||
5. Verify each header links to the previous header hash.
|
||
6. Use `GENESIS` to anchor the chain and `checkpoints.json` to accelerate SPV
|
||
verification.
|
||
|
||
If the Electrum fork does not yet implement BTCP's 120-block retarget logic,
|
||
set `SKIP_POW_DIFFICULTY_VALIDATION = True` temporarily for development only.
|
||
Do not ship a production wallet with difficulty validation disabled.
|
||
|
||
### 7.8 Electrum Wallet Build Checklist
|
||
|
||
Files that must be added or changed in an Electrum fork:
|
||
|
||
| File / area | Required BTCP change |
|
||
|-------------|----------------------|
|
||
| `electrum/constants.py` | Add `BitcoinPurple` and `BitcoinPurpleTestnet` classes |
|
||
| `electrum/chains/bitcoinpurple/servers.json` | Add real ElectrumX host(s), ports `50001` / `50002` |
|
||
| `electrum/chains/bitcoinpurple/checkpoints.json` | Generate from a synced BTCP node |
|
||
| header chain verifier | Use 120-block retarget and BTCP `powLimit` |
|
||
| address module | Accept Base58 versions 56/55 and Bech32 HRP `btcp` |
|
||
| transaction/wallet formats | Use `coin_type = 0` (mainnet) / `1` (testnet), matching Bitcoin Purple Core |
|
||
| Lightning invoice parser | Accept `lnbtcp` / `lntbtcp` BOLT11 prefixes if LN is enabled |
|
||
| UI/network selector | Expose BitcoinPurple mainnet/testnet names and datadirs |
|
||
|
||
---
|
||
|
||
## 8. Lightning Network
|
||
|
||
This section documents the chain-specific parameters required to build or fork
|
||
a Lightning Network implementation for BTCP. General BOLT protocol behaviour
|
||
(onion routing, payment flow, gossip) is identical to Bitcoin LN.
|
||
|
||
### 8.1 Chain Identification
|
||
|
||
In BOLT1, every message that references a specific chain carries a `chain_hash`.
|
||
This is the genesis block hash in **wire byte order** (i.e. the display hex reversed byte-by-byte).
|
||
|
||
| Network | Genesis hash (display) | chain_hash (BOLT1 wire) |
|
||
|---------|------------------------|-------------------------|
|
||
| Mainnet | `000003823fbf82ea…c015` | `15c04ef0bc1856d6b1ec199ca25d0aa7e77c6114e2cb0649ea82bf3f82030000` |
|
||
| Testnet | `000002fdc3921c1a…d998` | `98d9f92e8867ee945d5aab422bd49896497f58cc6f8168d31a1c92c3fd020000` |
|
||
|
||
The `chain_hash` appears in channel-establishment, channel-gossip, and gossip-query
|
||
messages such as `open_channel`, `accept_channel`, `funding_created`,
|
||
`channel_announcement`, `channel_update`, `query_channel_range`, and
|
||
`reply_channel_range`. BOLT11 invoices do not normally carry `chain_hash`; their
|
||
network is selected by the invoice HRP.
|
||
|
||
### 8.2 BOLT11 Invoice Prefix
|
||
|
||
| Network | HRP | Example invoice start |
|
||
|---------|-----|-----------------------|
|
||
| Mainnet | `btcp` | `lnbtcp1…` |
|
||
| Testnet | `tbtcp` | `lntbtcp1…` |
|
||
|
||
Amount suffix multipliers (same as Bitcoin):
|
||
|
||
| Multiplier | Value |
|
||
|------------|-------|
|
||
| `m` | 0.001 BTCP (100,000 sat) |
|
||
| `u` | 0.000001 BTCP (100 sat) |
|
||
| `n` | 0.000000001 BTCP (0.1 sat) |
|
||
| `p` | 0.000000000001 BTCP (0.0001 sat) |
|
||
|
||
### 8.3 Block-Time-Scaled Timeout Parameters
|
||
|
||
**This is the most critical section for LN on BTCP.**
|
||
|
||
BTCP has 1-minute blocks (vs Bitcoin's 10-minute blocks). All LN timeout parameters
|
||
expressed in blocks must be scaled by ×10 to achieve the same real-world security
|
||
windows as Bitcoin LN. Failure to do this results in dangerously short penalty and
|
||
payment expiry windows.
|
||
|
||
| Parameter | Source type | Bitcoin common default | BTCP recommended (1 min/block) | Real-world time |
|
||
|-----------|----------|------------------------|-------------------------------|-----------------|
|
||
| `to_self_delay` (justice window) | implementation policy | 144 blocks | **1440 blocks** | ~24 hours |
|
||
| `cltv_expiry_delta` per routing hop | implementation policy / BOLT7 field | 40 blocks | **400 blocks** | ~6.7 hours |
|
||
| `min_final_cltv_expiry_delta` (last hop) | implementation policy / BOLT11 field | 9 blocks | **90 blocks** | ~90 minutes |
|
||
| maximum remote `to_self_delay` accepted | BOLT2 policy limit | 2016 blocks | **20160 blocks** | ~14 days |
|
||
| `max_cltv_expiry` (max payment timeout) | implementation policy | 2016 blocks | **20160 blocks** | ~14 days |
|
||
| Channel funding confirmation target | best practice | 3–6 blocks | **30–60 blocks** | ~30–60 minutes |
|
||
|
||
> **Why this matters:** if a remote party broadcasts a revoked commitment transaction,
|
||
> your node has until `to_self_delay` blocks to publish the penalty transaction.
|
||
> With 1-min blocks and Bitcoin's default of 144, you would have only 2.4 hours.
|
||
> Using the recommended 1440 gives a full 24 hours — the same window as Bitcoin.
|
||
|
||
### 8.4 Channel Parameters
|
||
|
||
These match Bitcoin LN defaults and do not need to change for BTCP.
|
||
|
||
| Parameter | Value | Note |
|
||
|-----------|-------|------|
|
||
| `dust_limit_satoshis` | 354 sat (P2WPKH anchor) or 546 sat (legacy) | minimum output in commitment tx |
|
||
| `max_htlc_value_in_flight_msat` | 0 (unlimited) or % of capacity | channel-operator choice |
|
||
| `max_accepted_htlcs` | 483 | BOLT3 protocol maximum (script complexity limit) |
|
||
| `htlc_minimum_msat` | 1 msat | minimum HTLC size |
|
||
| `channel_reserve_satoshis` | ~1% of channel capacity (min 1000 sat) | reserves the counterparty cannot spend |
|
||
| `fee_base_msat` | 1000 (1 sat) | routing fee base |
|
||
| `fee_proportional_millionths` | 1 (0.0001%) | routing fee rate |
|
||
| `feerate_per_kw` | node-determined | initial commitment transaction fee rate |
|
||
|
||
### 8.5 Feature Bits (BOLT1 `init`)
|
||
|
||
LN feature bits are chain-agnostic; BTCP uses the same bit assignments as Bitcoin LN.
|
||
|
||
| Feature | Bit pair | Status |
|
||
|---------|----------|--------|
|
||
| `var_onion_optin` | 8/9 | mandatory |
|
||
| `option_static_remotekey` | 12/13 | mandatory |
|
||
| `payment_secret` | 14/15 | mandatory |
|
||
| `basic_mpp` (multi-part payments) | 16/17 | optional |
|
||
| `option_anchors_zero_fee_htlc_tx` | 22/23 | optional (preferred over legacy anchors) |
|
||
| `option_scid_alias` | 46/47 | optional |
|
||
| `option_zero_conf` | 50/51 | optional |
|
||
|
||
### 8.6 Shared Implementation Fork Notes
|
||
|
||
All major LN implementations (LND, CLN, Eclair, LDK) hardcode Bitcoin's chain hash.
|
||
Forking any of them for BTCP requires at minimum:
|
||
|
||
1. Replace the genesis hash / chain_hash constant with the BTCP value (§8.1)
|
||
2. Replace the BOLT11 invoice HRP with `btcp` (§8.2)
|
||
3. Update all block-count-based timeout defaults (§8.3)
|
||
4. Point the Bitcoin RPC backend to `bitcoinpurpled` on port `13495`
|
||
5. Update the network / bech32 address validation to accept `btcp1…` addresses
|
||
|
||
Also update any constants derived from Bitcoin's 10-minute block cadence:
|
||
confirmation targets, fee-estimation targets, CLTV deltas, wallet rescan
|
||
lookbacks, channel announcement depth policy, and watchtower/penalty windows.
|
||
|
||
### 8.7 Core Lightning (CLN) Fork Parameters
|
||
|
||
Core Lightning is Bitcoin-specific upstream. A BTCP fork needs a new chain
|
||
definition or equivalent patches wherever CLN selects `bitcoin`, `testnet`,
|
||
`signet`, or `regtest`.
|
||
|
||
| Area | BTCP mainnet value / action |
|
||
|------|-----------------------------|
|
||
| Network name | add `bitcoinpurple` / `btcp` network selector |
|
||
| Chain hash | `15c04ef0bc1856d6b1ec199ca25d0aa7e77c6114e2cb0649ea82bf3f82030000` |
|
||
| On-chain RPC backend | `bitcoinpurple-cli` / `bitcoinpurpled` RPC on `127.0.0.1:13495` |
|
||
| Bech32 address HRP | `btcp` |
|
||
| BOLT11 HRP | `btcp` (`lnbtcp...`) |
|
||
| Native unit | 1 BTCP = 100,000,000 sat; 1 sat = 1,000 msat |
|
||
| Genesis display hash | `000003823fbf82ea4906cbe214617ce7a70a5da29c19ecb1d65618bcf04ec015` |
|
||
| P2P gossip chain filter | accept only BTCP `chain_hash` |
|
||
| Fee estimates | call BTCP daemon `estimatesmartfee`; scale targets for 1-minute blocks |
|
||
| Confirmation policy | use 30-60 blocks where you want Bitcoin-like 30-60 minute confidence |
|
||
| Timeout defaults | use §8.3 scaled block counts |
|
||
| DNS bootstrap | empty until BTCP LN seed infrastructure exists |
|
||
|
||
CLN does not require Bitcoin Core ZMQ or `txindex=1` for normal operation; it
|
||
polls the backend over RPC. If CLN and ElectrumX share one `bitcoinpurpled`,
|
||
increase `rpcworkqueue` and monitor RPC latency.
|
||
|
||
### 8.8 LND Fork Parameters
|
||
|
||
LND uses btcsuite chain parameters and Bitcoin-specific network selection. A BTCP
|
||
fork needs equivalent new `chaincfg` / chain registry parameters.
|
||
|
||
| Area | BTCP mainnet value / action |
|
||
|------|-----------------------------|
|
||
| Chain registry | add BitcoinPurple params instead of `chaincfg.MainNetParams` |
|
||
| RPC backend | `bitcoind`-style backend pointed to `bitcoinpurpled:13495` |
|
||
| ZMQ raw block | `bitcoind.zmqpubrawblock=tcp://127.0.0.1:28332` if using ZMQ |
|
||
| ZMQ raw tx | `bitcoind.zmqpubrawtx=tcp://127.0.0.1:28333` if using ZMQ |
|
||
| Address params | P2PKH 56, P2SH 55, Bech32 `btcp`, WIF 183 |
|
||
| Chain hash | same §8.1 wire value |
|
||
| Invoice HRP | `btcp` |
|
||
| Coin type | `0` (mainnet) / `1` (testnet) — matches Bitcoin Purple Core wallet |
|
||
| Timeout defaults | use §8.3 scaled block counts |
|
||
| Fee estimator | ensure targets are interpreted as 1-minute BTCP blocks |
|
||
|
||
Unlike ElectrumX, LND normally benefits from ZMQ for prompt block/transaction
|
||
notifications. If ZMQ is omitted, use the implementation's RPC polling mode and
|
||
expect higher latency.
|
||
|
||
### 8.9 Lightning Difficulty / Block Cadence Implications
|
||
|
||
LN implementations do not recalculate proof-of-work difficulty themselves for
|
||
normal operation; the full node validates blocks. The LN daemon consumes validated
|
||
block headers/blocks from `bitcoinpurpled` and uses block heights for timeouts.
|
||
|
||
What must still be changed in LN code:
|
||
|
||
- Treat one BTCP block as ~60 seconds when converting user-facing time windows to
|
||
block counts.
|
||
- Use BTCP's `chain_hash` everywhere gossip or channel messages identify a chain.
|
||
- Use BTCP's address and BOLT11 HRPs for invoices, fallback addresses, and
|
||
on-chain outputs.
|
||
- Do not connect to Bitcoin LN peers or DNS seeds; BTCP LN needs its own network
|
||
graph and bootstrap peers.
|
||
|
||
---
|
||
|
||
## 9. `bitcoinpurple.conf` Reference
|
||
|
||
### 9.1 Default Values
|
||
|
||
| Parameter | Default | Source |
|
||
|-----------|---------|--------|
|
||
| `dbcache` | 450 MiB | `src/txdb.h:30` |
|
||
| `maxmempool` | 300 MB | `src/kernel/mempool_options.h:20` |
|
||
| `mempoolexpiry` | 336 h (14 days) | `src/kernel/mempool_options.h:24` |
|
||
| `blockmaxweight` | 3,996,000 wu | `src/policy/policy.h:23` |
|
||
| `rpcthreads` | 4 | `src/httpserver.h:12` |
|
||
| `rpcworkqueue` | 16 | `src/httpserver.h:13` |
|
||
| `rpcservertimeout` | 30 s | `src/httpserver.h:14` |
|
||
| `maxconnections` | 125 | `src/net.h` |
|
||
|
||
### 9.2 Full Annotated Config
|
||
|
||
```ini
|
||
##############################################################################
|
||
# bitcoinpurple.conf — full node + solo mining + ElectrumX backend
|
||
# Location: ~/.bitcoinpurple/bitcoinpurple.conf
|
||
##############################################################################
|
||
|
||
# ── Network ──────────────────────────────────────────────────────────────────
|
||
# mainnet by default; uncomment for testnet
|
||
#testnet=1
|
||
|
||
listen=1
|
||
maxconnections=125
|
||
# addnode=node3.walletbuilders.com
|
||
|
||
# ── Chain & Indexes ───────────────────────────────────────────────────────────
|
||
# txindex=1 is REQUIRED by ElectrumX — incompatible with prune
|
||
txindex=1
|
||
# blockfilterindex=1 # optional: BIP157/158 compact filters for light clients
|
||
# prune=0 # never prune when txindex=1
|
||
|
||
# ── Performance ───────────────────────────────────────────────────────────────
|
||
dbcache=450 # MiB (default: 450; raise on high-RAM machines)
|
||
maxmempool=300 # MB (default: 300)
|
||
mempoolexpiry=336 # hours before unconfirmed txs are evicted (default: 336 = 14 days)
|
||
|
||
# ── RPC Server (required by ElectrumX) ───────────────────────────────────────
|
||
server=1
|
||
rpcport=13495
|
||
rpcbind=127.0.0.1
|
||
rpcallowip=127.0.0.1 # set to container subnet when ElectrumX is in Docker
|
||
rpcuser=btcpuser
|
||
rpcpassword=CHANGE_ME_USE_STRONG_PASSWORD
|
||
rpcthreads=4
|
||
rpcworkqueue=64 # raised from default 16 for ElectrumX parallel RPC calls
|
||
rpcservertimeout=30
|
||
|
||
# ── ZMQ Notifications (optional real-time updates) ───────────────────────────
|
||
zmqpubrawblock=tcp://127.0.0.1:28332
|
||
zmqpubrawtx=tcp://127.0.0.1:28333
|
||
zmqpubhashblock=tcp://127.0.0.1:28334
|
||
zmqpubhashtx=tcp://127.0.0.1:28335
|
||
zmqpubrawblockhwm=500
|
||
zmqpubrawtxhwm=500
|
||
zmqpubhashblockhwm=500
|
||
zmqpubhashtxhwm=500
|
||
|
||
# ── Mining ────────────────────────────────────────────────────────────────────
|
||
# MAX_BLOCK_WEIGHT = 4,000,000 wu (consensus/consensus.h:15)
|
||
blockmaxweight=3996000
|
||
blockmintxfee=0.00001
|
||
# blocknotify=/usr/local/bin/notify_new_block.sh %s
|
||
|
||
# ── Wallet (disable if mining to an external address via getblocktemplate) ───
|
||
# disablewallet=1
|
||
```
|
||
|
||
### 9.3 Notes
|
||
|
||
- **`txindex=1` and `prune` are mutually exclusive.** ElectrumX requires `txindex=1`.
|
||
- **ZMQ** requires `--enable-zmq` at build time. Verify: `bitcoinpurple-cli getnetworkinfo | grep zmq`. ElectrumX can index through RPC polling; LND-style backends usually use ZMQ for low-latency block/tx notifications.
|
||
- **Solo mining** via `getblocktemplate` (BIP22): point your miner to `http://btcpuser:CHANGE_ME@127.0.0.1:13495`.
|
||
- **Docker networking:** set `rpcallowip` to the container subnet (e.g. `172.17.0.0/16`) when ElectrumX runs in a separate container.
|
||
- **LN node:** the LN daemon also connects to `bitcoinpurpled` via RPC. Set `rpcworkqueue` high enough (128+) if both ElectrumX and an LN node share the same node instance.
|
||
|
||
### 9.4 Minimal ElectrumX `env` (standalone / non-Docker)
|
||
|
||
```env
|
||
COIN=BitcoinPurple
|
||
NET=mainnet
|
||
DAEMON_URL=http://btcpuser:CHANGE_ME@127.0.0.1:13495/
|
||
DB_DIRECTORY=/data/electrumx
|
||
SERVICES=tcp://0.0.0.0:50001,ssl://0.0.0.0:50002,rpc://0.0.0.0:8000
|
||
REPORT_SERVICES=tcp://YOUR_PUBLIC_IP:50001,ssl://YOUR_PUBLIC_IP:50002
|
||
SSL_CERTFILE=/certs/server.crt
|
||
SSL_KEYFILE=/certs/server.key
|
||
CACHE_MB=1200
|
||
MAX_SESSIONS=1000
|
||
INITIAL_CONCURRENT=2
|
||
COST_SOFT_LIMIT=0
|
||
COST_HARD_LIMIT=0
|
||
PEER_DISCOVERY=on
|
||
PEER_ANNOUNCE=true
|
||
```
|