How to Create Your Own Onchain Index Token

What an Onchain Index Token Really Is

To create an onchain index token is to mint a single ERC-20 backed in-kind by a basket of real assets held in a smart-contract vault. Buy one token and you own the whole basket proportionally; redeem it and the vault returns the underlying. Every token in circulation stays backed 100% by the assets it represents: no synthetic exposure, no IOU, no custodian holding your coins.

It's the onchain answer to an exchange-traded fund. Launch an onchain ETF this way and its rules live in immutable contract code instead of a prospectus, while anyone can verify the holdings at any block. On Tessera, which runs on Base, the basket is the core product, and creating one is permissionless. No gatekeeper approves your idea.

Design Your Thesis First

Before you touch any settings, decide what your index expresses. A good basket is an argument: a bet on Base memecoins, blue-chip majors, a specific sector, or yield. That thesis drives every choice that follows.

Tessera baskets come in two families:

• Index: narrative and momentum baskets built from tokens like WETH, cbBTC, AERO, and DEGEN, meant to track a story or a sector.
• Earn: yield-bearing baskets built from liquid staking tokens like wstETH and cbETH, plus ERC-4626 vaults from protocols such as Beefy, Yearn, Aave, Morpho, Moonwell, and Euler, which compound while a holder simply holds.

When you make a token basket, you can combine 2 to 30 underlying assets. Fewer assets make a sharper, higher-conviction bet; more assets spread risk and smooth volatility. A tight three-token majors index reads very differently from a twenty-token sector sweep, and both are valid.

Set Your Weights, Name, and Ticker

With your members chosen, you create your index token by assigning weights. Weights decide how much of each asset the basket holds: an equal-weight basket treats every member the same, while a conviction-weighted basket tilts hard toward one or two names. This is where your thesis becomes math.

Then give it an identity:

• Name: human-readable, like "Base Majors" or "Blue-Chip Yield."
• Ticker: a short symbol for the ERC-20 itself.

That's the whole design. There's no code to write and no contract to audit yourself. The platform assembles a standard, verifiable ERC-20 vault from your inputs. Choosing a clear name and honest weighting is most of the work when you create a crypto index that others will actually want to hold.

Deploy Once: It's Immutable

When you deploy, the basket and its weights are locked forever. There's no admin key, no upgrade path, and no way for you or anyone else to swap a token, change a weight, or drain the vault later. That immutability is the point: holders can trust the rules because the rules cannot move.

This makes the choice to create an ETF onchain a genuinely different act from managing a traditional fund. You're not a manager with discretion; you're the author of a fixed rule set that then runs on its own. Get your thesis and weights right before you ship, because the only way to "rebalance" is to launch a new basket.

Non-custodial by design, holders always keep their own tokens in their own wallets. Nothing about your basket lets you touch their funds.

How Buyers Get In With One Trade

A basket is only useful if it's easy to buy. On Tessera a buyer pays with USDC or ETH on Base, and a single transaction routes that deposit across up to about six venues (Uniswap v2, v3, and v4, Aerodrome, and ERC-4626 vaults) to assemble every leg atomically.

The buyer never shops for the underlying tokens one by one, never manages slippage leg by leg, and never ends up with a half-filled basket. They press buy once and receive your index token, fully backed. Redemption runs the same way in reverse, at any time.

For you as a creator, low friction is what turns a clever thesis into real holders and real volume.

How Creators Earn Fees

A small fee applies whenever someone buys or sells a basket, and the creator of that basket earns a share of it. The more your index trades, the more you earn, so distribution and a thesis people believe in are your real growth levers.

There's a second earning path on the platform: holders who stake the platform token, TSR, earn 50% of platform fees, paid in USDC. That's separate from your creator share, but it's worth knowing how value flows before you launch.

None of this is a promise of profit. Fees follow volume, and volume follows whether your basket is actually good.

Know the Risks Before You Launch

An onchain index token is a DeFi product, not a regulated security or a traditional ETF, and nothing here is financial advice. Creating or holding one carries real smart-contract risk and real market risk. A basket's value moves with its underlying assets and can fall sharply.

Because baskets are immutable, a design mistake is permanent: you can't patch a bad weighting, only launch a replacement. Do your own research on every token you include, understand the ERC-4626 vaults in any Earn basket, and be honest in your basket's name and description.

Everything is verifiable onchain, which cuts both ways: your good decisions and your bad ones are equally permanent and public. Design accordingly.