Integrate a wallet or marketplace

Integrating GL-36 means reading one account per collection and decoding a fixed layout. There is no metadata standard to resolve and no indexer to run.

Recognize a collection

An account is a GL-36 collection when all of these hold:

• its owner is the GL-36 program;
• byte 0 is 0x01 and byte 1 is 0x01;
• its length equals 224 + minted × 36, with minted read from bytes 6–7.

decodeCollection checks the tag and version and throws otherwise.

Tokens owned by a wallet

Keep a list of collections you support, read them, and filter slots by owner:

import { decodeCollection, slotsOwnedBy } from "@gl36/sdk";

async function owned(collections: Address[], wallet: Address) {
  const { value } = await rpc
    .getMultipleAccounts(collections, { encoding: "base64", commitment: "confirmed" })
    .send();
  return value.flatMap((acc, i) => {
    if (!acc) return [];
    const col = decodeCollection(new Uint8Array(Buffer.from(acc.data[0], "base64")));
    return slotsOwnedBy(col, wallet).map((s) => ({ collection: collections[i], id: s.id, listed: s.price > 0 }));
  });
}

getMultipleAccounts reads up to 100 collections in one request. For a single collection, fetchCollection does the read and the decoding in one call.

To discover collections you don’t know about, list the program’s accounts: getProgramAccounts with a memcmp filter on byte 0 = 0x01, or a dataSlice of the first 224 bytes to fetch headers only.

Keep state fresh

The account is the state. Two ways to follow it:

• Polling. Re-read with getAccountInfo every few seconds and after each transaction you send. A 5,000-token collection is about 180 KB.
• Subscription. accountSubscribe over WebSocket pushes the new bytes on every change.

To show history — who minted, who sold at what price — read the program logs of the collection’s transactions with getSignaturesForAddress and getTransaction. See Logs.

Floor and listings

const listed = col.slots.filter((s) => s.price > 0).sort((a, b) => a.price - b.price);
const floor = listed[0] ? Number(BigInt(listed[0].price) * PRICE_UNIT) / 1e9 : null;

Build a safe purchase

Always pass the owner and price you displayed to the user. If either changed by the time the transaction runs, it fails with SellerMismatch (6) or PriceAboveMax (5) instead of paying more.

const s = col.slots[id];
const ix = buyIx(PROGRAM, buyer, COLLECTION, s.owner, col.treasury, id, s.price);

The buyer must hold the price plus the network fee. The market fee comes out of the price, not on top of it.

Show content

Before reveal (flags & 1 === 0), show a placeholder: content does not exist yet. After reveal, compute the seed from the header and the id, run the collection’s generator, and check the generator file against generator_hash before trusting its output. See Provenance and reveal.

Explain errors

Program errors arrive as custom program error: 0x… inside a kit SolanaError or the simulation logs. parseProgramError finds the code wherever it is and names it. Pass programId so an error raised by another program, such as the System Program’s insufficient funds, isn’t mistaken for one of GL-36’s.

import { PROGRAM_ID, parseProgramError } from "@gl36/sdk";

const err = parseProgramError(e, { programId: PROGRAM_ID.devnet });
if (err?.name === "SellerMismatch") showMessage("This token was just sold or moved. Refresh and try again.");

The full table is in Errors.