Introducing Bastion Stableswap

6 min readApr 4, 2022


Bastion Stableswap

Introducing Bastion Stableswap, the low-slippage AMM for stablecoins, cTokens, wrapped, and staked assets on Aurora.

Yield-on-yield savings account. Multichain gateway. Algostable magnified peg stabilizer. Interest-rate swaps and cross-Realm arbitrage. veTokens and gauge systems for both our Lending and Stableswap. The Hub of Aurora, and more. Are you ready for the Bastion Wars?

Unlike normal AMMs like Uniswap or Trisolaris, Stableswap AMMs employ a different curve that allows for lower slippage between assets with close prices. Lending (Aave and Benqi) and Stableswap (Curve and Platypus) make up 70% of Avalanche’s TVL! Users shouldn’t have to choose between LP yield or deposit yield. Why not stack them?

Since Aurora is so new, we have a chance for Bastion to do both. We strive to be the most sustainable, high-yield savings account in all of DeFi. Bastion’s lending product already controls almost 50% of Aurora TVL. There is no protocol on any other ecosystem that dominates both Infinity Stones in the DeFi gauntlet.

DeFi Gauntlet


  • Traders can trade stable pairs with lower slippage, lower fees, and higher capital efficiency.
  • LPs can provide single-sided liquidity (as opposed to 50/50 for 2 assets on normal AMMs), and experience much lower impermanent loss risk due to the StableSwap curve. Since LP positions will be cToken-based, users can earn yield-on-yield. For example, a cstNEAR-cNEAR LP will be able to stack NEAR Staking Rewards + Deposit APY + LP Yield + BSTN Rewards + META Rewards + NEAR Liquidity Mining Rewards.
  • BSTN Holders will benefit from BSTN gaining double the utility than before, with veTokenomics and gauge systems creating scarce supply and high demand.
  • Lending depositors get more market-efficient interest rates through cross-Realm interest-rate swaps and arbitrage.

Next steps

Our Stableswap is now live on Aurora Mainnet. Initially, there will be a cUSDC-cUSDT pool, with more pools and BSTN rewards coming shortly after.


There are deep synergies with having both a Stableswap and Lending controlled by a single protocol. “The whole is greater than the sum of the parts.”

Innovative additions include:

  1. Make cTokens the base asset of the Aurora ecosystem
  2. Double the BSTN utility
  3. Ignite Bastion wars with veTokenomics connecting Stableswap AND Lending gauges
  4. Make Bastion the multichain gateway of Aurora
  5. Supercharge algorithmic stablecoins with a magnified peg stabilization module
  6. Stables Isolated Realm x Leveraged yield farming
  7. veTokens with lending and Stableswap gauges
  8. Bastion Wars: Convex-like derivatives
  9. Interest-rate swaps between different multichain wrapped versions and cTokens from different realms, resulting in much more market-efficient interest-rate rebalancing
  10. Yield-optimizer vault built on top of interest-rate swaps
  11. An innovative fee model for LPs ;)
  12. Protocol-owned liquidity
  13. Self-repaying loans

Every idle asset should be an interest-bearing cToken

Our first ever announcement outlined:

“The ultimate vision for Bastion is to be the liquidity hub of NEAR, where no asset lies unproductive and composable cTokens form the base of the ecosystem.”

Our Stableswap pools will focus on cTokens to begin with. Collateral tokens (i.e. cTokens) are the receipt token users receive after depositing into Bastion. cTokens automatically generate interest, and can be treated like any other normal ERC-20. Why use USDC when you can simply deposit into Bastion and trade around cUSDC while passively earning deposit interest? This logic applies to any token!

Aurora is uniquely positioned to be the first DeFi ecosystem where cTokens are more widely used than the underlying assets themselves. We are so early that cultural norms, and asset usage adoption are still not set in stone. In contrast, it would be a huge and difficult paradigm shift for existing ecosystems to redirect and uproot all their existing pools to cTokens.

Much like Terra powers their ecosystem with native staking rewards from LUNA, we envision a future where all Aurora assets are passively earning yield on Bastion and users won’t even realize it. Imagine if all the USDC on Aurora was cUSDC!

BSTN Tokenomics

BSTN will now govern both a Stableswap and Lending protocol and veBSTN will control both gauge systems. With double the utility, we aim to ignite the Bastion Wars. Multichain algostables and protocols on Aurora will fight for boosted BSTN emissions.

The only long-term moat is the composable ecosystem built on top of Bastion. Convex-style derivatives? Yield optimizers? Lossless lotteries? Much more.

Make Bastion the multichain gateway of Aurora

The only way we can make cTokens the default asset of Aurora is if Bastion serves as the gateway to Aurora. Stableswaps are the first point-of-contact a user has when switching between wrapped version of assets from different bridges. We will make the conversion to cTokens seamless.

In a multichain world, Layer-1’s will be as connected as ever. Users will quickly flock to Aurora when they realize that fees and transaction speeds are much faster than any other EVM out there. Seamless Layer-0 Lending and Multichain Swapping, coming soon…

Stables Isolated Realm x Leveraged yield farming

Since stablecoins will be the shared lifeblood between our Realms, we expect our upcoming Stables Realm to be Bastion’s Central Nervous System where users can get high leverage with little liquidation risk and low rates. DAO-To-DAO partnerships such as a magnified peg stabilization module for algorithmic stablecoins are also possible.

Interest-rate swaps

Liquidity on Aurora will be greatly fragmented with multiple wrapped versions of assets and cTokens from different Realms. Our Stableswap unites this liquidity through a smart router, allowing for interest rate swap arbitrage and much more market-efficient interest-rate rebalancing between Realms. Yield-optimizer vaults can be built on top to automate this process, making the user experience extremely easy.

Protocol-owned liquidity

(3, 3)… more soon.

L. F. G.

This is the next chapter for Bastion. Thank you, Aurorians. We will make you proud.


The Bastion Team

Be the First Employee of NEAR’s biggest protocol

We’re hiring for a: Founding Engineer, Research Lead, Business Development Lead, Community Lead, Design Lead, DAO builders, and Degen Interns.

Salary: $150k — $500k packages (technical); $120k+ packages (non-technical). Tokens included!

Contact: with Twitter, Github, and/or resume

About Bastion

Bastion is a decentralized lending and borrowing protocol built on Aurora, NEAR’s EVM-compatible layer. Building on Aurora enables Bastion to create an autonomous interest-rate engine with superior capital efficiency, fast transactions, ultra-low transaction fees, precise liquidations, and harness the underlying UX benefits of NEAR.

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DISCLAIMER: This article does not constitute investment advice. Bastion Protocol Token (BSTN) is a means by which users may utilize and govern the protocol. Bastion does not recommend purchasing BSTN for speculative investment purposes. BSTN tokens may lose value or have no value and may have no market. Please read the full disclaimers here.