lsc.kil.ls / LSC
A stable-node ledger with offline-redeemable stamps, three physical carriers (NFC tokens, magnetic stripe vouchers and chip cards) and a chain-native clock. Specified in a reference paper and three RFCs, written as RPython reference code.
Architecture · Reference Paper §0
Not an open miner race: a small, known cohort of producers, a segmented block body and a clock that never trusts a wall clock after genesis. There is deliberately no privacy layer. Sender, receiver and amount are plainly attributable on-chain.
A fixed cohort of 24 identified LSC nodes instead of an open miner race. At most 7 may act Byzantine.
Blocks are many small, typed segments. LIGHT_PASS runs ChaCha20, HEAVY_PASS Argon2id. No compression, no reconstruction.
A quarter of each block carries aggregated latency probes: enough to spot a dark node, not a targeting map.
Non-transferable claims baked into a coin's own definition. Claiming one produces a movable coin in a wallet.
Ten signed UTC samples once, then time is threaded from chain structure. Changing the formula needs all 24 nodes.
ECVRF (RFC 9381) picks the producer, a total order picks the chain, a 16-of-24 checkpoint makes it final.
Small micro-proofs (NeoScrypt, RandomX, Equihash) split the block reward by proven work. Rewards mature for three hours.
Fourteen independent features on three verification tiers, modelled on the security architecture of the Lesotho loti.
New features arrive as soft forks: new segment types, activation heights and a ParameterRegistry.
Two-layer coin economy · §5
Non-movable until claimed
Stamp-only coins live at the issuance layer. Claiming one produces a movable coin in a wallet, and wallets only ever hold movable coins.
Mining maturity is a stamp
Block rewards are minted held for three chain-time hours and unlock on the next full hour. No separate contract system.
Carriers make stamps portable
An NFC token, a stripe voucher or a chip card refers to a stamp. Each carrier only authorizes a claim; the ledger settles it once.
Redemption · Reference Paper §18
An offline NFC redeem is a locally persisted claim request; only canonical online reconciliation can establish ledger finality.
| Carrier | Offline? | Value limit | Copying and clones | Spec |
|---|---|---|---|---|
| NFC token | Yes, as a pending request | 100 LSC per token, secure element above 50 | Copyable; replay table and idempotent settlement | RFC-001 |
| Magnetic stripe voucher | No, online only | Face value ≤ ε_M (1 LSC without PIN) | Fully copyable; second attempt is clone evidence | RFC-002 |
| Chip card | Yes, within card-enforced credit | U_max 500 LSC, PIN from 20 LSC | Key never leaves card; duplicate counter is evidence | RFC-003 |
01 / 04
RFC-001 §7 · no network needed
Tap a token on a device with no connection. The device checks what it can check on its own, then stores a signed claim request. It never pretends the coin has moved, and it never reports success if the write to its encrypted store failed.
Simulated redeem
DECODED
Tap token
magic=LSCNFC version=1 network=lsc-main token_id=7f3a… stamp_id=c21e…
The LSCNFC payload is decoded as strict TLV. A wrong magic, an unknown version, another network or any non-canonical byte is rejected, never repaired.
token = NFCToken.decode(raw)Issuer signature, claim window against the local chain index, OTP checkpoint format, revocation list and snapshot reference above 50 LSC.
token.verify(network_id, chain_index)Above 50 LSC a secure element is mandatory (E_SE_REQUIRED). Above 100 LSC per token the request is refused (E_OFFLINE_LIMIT).
A token already used on this device is refused before anything is signed. A burned one-time tag gives E_TOKEN_CONSUMED.
request_id = H(network ‖ token ‖ stamp ‖ redeemer ‖ nonce). The request is written atomically to the encrypted store before the device reports anything.
store.put(request) → PENDING_ONLINEWhat the device can report
02 / 04
RFC-001 §8 · against the canonical ledger
When a request reaches the network, the settlement service checks it again from scratch, claims the stamp on the real ledger and releases a movable coin. NFC requests, card requests and stripe vouchers all end here.
A request_id that already settled returns the original response. The same request_id with a different payload is E_REQUEST_REPLAY.
settled[request_id]The service trusts nothing the device decided: request signature, token, network, issuer key and that the request matches the issued token.
The device's chain context must lie within 5 blocks of the canonical ledger, otherwise the request stays PENDING.
|local_index − canonical_index| ≤ 5The stamp moves CLAIMABLE → CLAIMED and a multi-output transfer pays the beneficiary and the fee collector. Any failure rolls back exactly.
claim_stamp() + apply_transfer()What the ledger answers
03 / 04
RFC-002 · online only
A stripe is static and fully copyable, so RFC-002 does not pretend it is secure. It bounds the damage instead: a 128-bit secret on the stripe, only a commitment in the register, one online redemption, and a face value no larger than the loss the issuer accepts.
A voucher is not a payment card and never touches payment networks.
Track 1 carries the 128-bit voucher secret in Base32 with four check characters. It is deliberately not a bank-card layout, and the terminal never logs the secret.
%F LSC1 ^ m ^ K(26) ^ X(4) ?The registered terminal signs version, network, its strictly increasing counter, the secret, payout address and an 8-byte nonce. TLS on top.
request_id = H(net, C, terminal_id, nonce)The register stores only C = H(DOM_CL, k, issuer_id), never k. A leaked register cannot redeem anything.
State, validity and optional PIN are checked, then the voucher is set to REDEEMED and the payout is queued. The payout retries until it is in a block.
Value limit and exposure (§8.4, §10)
04 / 04
RFC-003 · offline within card credit
The card holds no coins. It is a secure element that authorizes requests: a non-exportable Ed25519 key, a counter that can never repeat, an offline credit limit it enforces itself, and an optional PIN. A clone shows up as two requests with one counter, and its damage is bounded by c · (U_max − u₀).
Command set (§8.1)
| 00 A4 | SELECT | AID F0 4C 53 43 01 |
| 80 10 | GET STATE | pk, counter, credit, limit |
| 00 20 | VERIFY | PIN block |
| 80 40 | SIGN REQUEST | digest + amount |
| 80 50 | RESET CREDIT | service-signed |
| 80 52 | UNBLOCK PIN | service-signed |
The terminal reads the NFC token or a QR code and hashes what the card will authorize: network, token, stamp, redeemer and amount.
D = H(DOM_REQ, net, token_id, stamp_id, redeemer, amount)From 20 LSC the card requires a successful VERIFY in the same session. Three wrong PINs block it until the service unblocks it.
The card checks state, the 100 LSC token limit and its credit, then commits counter and credit atomically to NVM. Only after that does the signature leave the card.
80 40 00 00 D(32) amount(8) → c′(8) sig(64)The attestation reference becomes the nonce. From here the request travels the same way as an NFC redemption.
nonce = se:<card_id>:<c′>The service checks the certificate, the attestation and that the counter is strictly greater, then signs a RESET CREDIT for the settled amount.
80 50 00 00 r′ = r_d + 1Chain-native clock · §6–§7
Blocks 1–10 carry signed UTC from the first ten nodes. Their median becomes the genesis anchor G. After that every height has a fixed time, t(h) = G + 60·h + Ah, with a drift adjustment of at most 5 s per 10 blocks.
Demonstration ticker · not a live network
Library
Paper 2.0
The complete protocol: stable nodes, segments, stamps, chain clock, fork choice and finality, mining, redemption, the terminal layer and the banknote-inspired security layers.
5 October 2026 · 55 pages · English · Draft
RFC-001
NFC tokens, offline redeem requests, online settlement and ledger snapshots. Profile v1 fixes encodings, the secure-element profile and key records.
6 October 2026 · 28 pages · English · Draft
RFC-002
Single-use vouchers on magnetic stripe cards: commitment register, online-only redemption, a formula-based value limit and clone detection.
6 October 2026 · 9 pages · English · Draft
RFC-003
An LSC applet for contact and contactless chip cards: APDU command set, atomic counter, card-enforced offline credit, PIN and card certificate.
6 October 2026 · 9 pages · English · Draft
Primitive inventory · §14.1.3
BLAKE2b-256
RFC 7693
Block, body and request hashes
Ed25519
RFC 8032
Every signature, domain-separated
ECVRF
RFC 9381
Slot lottery and leader selection
ChaCha20
RFC 8439
LIGHT_PASS, storage, terminal channel
Argon2id
RFC 9106
HEAVY_PASS, 64 MiB, 3 passes
SHA-256
FIPS 180-4
Dual-hash serial, wallet checksums
BIP-39 / SLIP-0010
BIP-39
Seed and key derivation
Bech32
BIP-173
Addresses, prefix lsc
Source
lscoin-rpython.zip (206 KB)
lscoin-rpython/
# translate into standalone binaries
pypy rpython/bin/rpython -O2 targetnode.py
pypy rpython/bin/rpython -Ojit targetminer.py
pypy rpython/bin/rpython -O2 targetnfcclasses.pyEU AI Act, Art. 50
Claude
by Anthropic
Wrote the Reference Paper 2.0, RFC-001 to RFC-003, the RPython reference code and this static site.
Grok
by xAI
Built the first version of this website and generated the coin and NFC token images (Grok Imagine).
Concept, direction and review: Florian
LanternSeaCoin is an engineering thought experiment with reference code. It is not an active, deployed or audited cryptocurrency: there is no mainnet, no issued supply, no token sale and no exchange listing. Nothing on lsc.kil.ls is an offer to sell, a solicitation to buy, or financial advice. The empirical validation of Reference Paper §15.9 (internal testnet, independent review, public testnet, economic audit) has not been carried out.