TIP-005 Threshold USD (thUSD) - interest-free loans with tBTC as collateral

[Agoristen]

TL;DR
Fork Liquity Protocol to build a decentralized stablecoin (Threshold USD - thUSD) purely backed by tBTC. Make Threshold DAO owner of the protocol and distribute profits through T buybacks and/or PCV.

This is a way to generate profit for Threshold Network while simultaneously encouraging adoption of tBTC by making it a collateral that can be borrowed against.

Introduction:
Liquity Protocol launched in April 2021 and is a decentralized borrowing protocol that allows you to draw interest-free loans against Ether used as collateral. Loans are paid out in LUSD (a USD pegged stablecoin) and need to maintain a minimum collateral ratio of 110%.

In addition to the collateral, the loans are secured by a Stability Pool containing LUSD and by fellow borrowers collectively acting as guarantors of last resort.

Here’s a quick overview:

Liquity presentation for ETHOnline

Whitepaper: https://docsend.com/view/bwiczmy
Documentation: https://docs.liquity.org/

Why?
In order for tBTC to become an attractive wrapper for BTC it needs use-cases. Integration with existing platforms are important, but so is looking for alternative ways to expand the tBTC ecosystem on its own.

Decentralized borrowing with BTC collateral on Ethereum is hard to come by. Some platforms allows you to borrow against WBTC, renBTC etc, but these wrappers suffer from various degree of centralization. The most popular wrapper (WBTC) custodies funds and operates minting/unminting process via a multisig federation. This degree of trust is not acceptable to many bitcoin holders. Solving the trust issue will allow more people borrow against their BTC.

Furthermore, these platforms generally offer variable interest rate and this results in uncertainty for borrowers because interest rates are highly dependent on market conditions. Because of this, long-term loans (e.g borrow to buy real estate or other “real-world” assets) becomes risky and difficult to maintain.

Interest free loans backed by tBTC collateral will enable bitcoin holders to borrow against their BTC in a trustless manner, without involvement of custodians or similar forms of centralization risk. Liquity Protocol is “pay once” (issuance fee starts at 0.5%) and borrow for as long as you like.

Given that a stablecoin (Threshold USD - thUSD) will be minted, this use-case also enables a purely decentralized stablecoin 100% backed by BTC - itself a very attractive prospect.

There is a fee of minimum 0.5% for each loan, and there is a minimum fee of 0.5% for redemptions (don’t worry, paying back your loan is always free - redemptions is people exchanging thUSD for tBTC).

Parts of the profits from usage of the protocol can be distributed to Threshold Network, thus giving us an additional income stream for T DAO.

Liquity Protocol is immutable, it cannot be altered. This is a “set and forget” type of platform. We pay the cost of development once and reap the reward forever. Liquity Protocol has been battletested well, at one point topping $1.5b LUSD in circulation.

source: Liquity

The single largest known actor (Justin Sun) at one point had a deposit of 669,000 ETH in the protocol:

The team behind the Liquity Protocol has carefully tested and audited the protocol to perfection. It’s both a solid project and team.

Forking the project should be fairly simple and only involve minor changes to fit our needs.

How can Threshold Network profit?

In Liquity Protcol, a token “LQTY” is distributed to depositors in the stability pool. It’s akin to liquidity mining / yield farming. Deposit LUSD into the pool and get paid LQTY rewards. The higher your % of the LUSD in the pool is, the higher % of the LQTY you will be farming.

The token distribution is ongoing for 35 months with a max supply of 100,000,000 LQTY. No further LQTY will be issued.

The chart above show issuance for the first 35 months. The rest of supply (~70M) is mostly reserved to initial investors & team.

Once 100M is minted the stability pool will not earn any LQTY, but the stability pool still present an opportunity to profit:
Whenever a user is liquidated (110%) the stability pool (which consists of LUSD) uses LUSD to buy the collateral (ETH) of the user at discount (~10%). By withdrawing the ETH and selling it on market, this can result in up to 10% profit for each liquidation.

The stability pool of Liquity shares many characteristics with coverage pools implemented in KEEP, and later Threshold Network. The funds are in both cases used to cover liquidations. This is arguably a much better design than auctions that are both unreliable and costly during times of high market stress, it yields a high degree of predictability and margin of safety that are not easily accomplished the auction way. Even though I do not make this a part of current proposal, it might even be that stability pool and coverage pool can be combined for maximum capital efficiency.

The LQTY token, when staked. earns profit from all loans and redemptions. Someone borrows $1,000,000 ? The protocol makes (at minimum) $5000. That profit is then split among all LQTY staked.

E.g if there is 100,000 LQTY total staked and you have personally staked 1000 LQTY, a loan of $1,000,000 will result in ($5000 / 100,000) * 1000 = $50 LUSD being added to your personal account.

However, when you really think about it, the LQTY token is just bloat. It serves no purpose other than incentivizing the stability pool growth early on. Once it’s no longer issued, it becomes a drain on the system. Profit from lenders are distributed to passive LQTY holders (whom provide no additional value to the protocol).

Yes. In this proposal, I suggest to eliminate the LQTY token altogether and replace it with a different mechanism:

Without LQTY token, we have several new options on how to split profits form the protocol:

1. Stability pool
2. T-token buy backs
3. PCV (Protocol Controlled Value - T DAO owned funds deposited in the stability pool)

By distributing profits into the stability pool, we can ensure that the long-term sustainability of the protocol is maintained. Liquity Protocol assumes that the liquidation rewards (~10%) is enough to maintain the pool, and that may very well be true, but having an additional profit stream into the stability pool will give us another layer of security.

How much % should be sent to the stability pool is up for debate and can be controlled by the T DAO. It might be worthwhile to implement a hardcoded minimum %, but beyond that it can be adjusted by the DAO to fit our needs. E.g: if there’s not enough funds in the pool, we vote to increase the % of profits going into the pool and vice-versa.

Depositing profits into the stability pool is in essence “renting liquidity”: The more profits is sent into the pool, the more liquidity we can expect it to contain. There’s an equilibrium to aim for (an amount of funds that will be sufficient to cover liquidations during big crashes / black swan events), beyond that, it’s wasted capital. If we find that the pool is large enough, the rewards can be reduced and vice-versa.

However, renting liquidity means we have to keep paying. We may decide that Protocol Controlled Value (owned liquidity) is better than distributing profits into the stability pool (rented liquidity). I personally believe this may be an even better and more exciting option because T DAO will retain ownership and continue to control the pool liquidity. With rented liquidity we have no control over the pool and there may be times, such as under high marked volatility or black swan events that pool liquidity vanishes and where even increasing rewards will not be sufficient to bring the pool liquidity back.

If we want to go with PCV, this can be accomplished either in combination with the above or by simply by abolishing stability pool distribution altogether and direct profits (thUSD) into the PCV’s stability pool position. If we do this, it should be further automated with selling of liquidated tBTC for more thUSD or other stablecoins (B-Protocol already does this - maybe we can fork their system?). That way the PCV will continue to grow over time and create a large buffer for the protocol.

The T-token buybacks is where Threshold Network holders will directly benefit from this proposal. It will help increase value of Threshold Network anytime a loan is drawn or a redemption is performed. Profits distributed as thUSD can be automatically converted to T which is then burned. This will result in consistent upward price-momentum as long as the lending protocol is in use.

Additionally it helps to preserve the thUSD peg given its soft-ceiling and hard-floor that naturally draws it to the upside and in need of some downward pressure.

But we need to bootstrap the protocol

LQTY token serves that purpose, without it, it will be harder to bootstrap the pool. When Liquity Protocol launched, the pool had tens of millions of LUSD within hours. We want to accomplish something similar, without the LQTY token.

There are some options:

1. Distribute 100% of profits into the stability pool for the first 3-6 months to encourage liquidity
2. Buy tBTC from the sale of T, lock tBTC as collateral on the platform and borrow thUSD. Place the thUSD into the stability pool.
3. Direct 100% of profits into the PCV and hope people use the platform enough to build a PCV.
4. A combination between 1 & 3
5. Direct T rewards to the stability pool (just like how T DAO directs rewards to coverage pool)
6. Raise thUSD from the sale of T

I’m going to assume 2. is a non-starter due to complexity in maintaining margin in a DAO.

If we go with 1. the first people who enter the pool stand to gain the most because everyone who deposits after them have to pay the borrow fee (0.5%). That will bootstrap initial liquidity to launch the protocol, however, profits will soon come to an halt after the initial rush of depositors have made their deposits and that could soon after result in liquidity bleed.

The protocol requires ongoing activity (people borrowing, or doing redemptions) in order for profits to be generated. Without LQTY rewards, it’s possible that activity will die down after the initial hype and that will make the APR bad in stability pool, which means people leave with their capital. To accommodate that risk we could instead (according to 3.) allocate less than 100% into the stability pool and allocate some into the PCV. For example 50% into stability pool, and 50% into PCV. Directing some % to the PCV immediately on launch is probably a good idea to establish funds that will not leave the pool even during periods of little activity (and thus profits).

But, if we do some back-on-the-envelope math:

100 million deposited = 500k profit

500k / 2 = 250k

The PCV will be $250k, profit to stability pool depositors: $250k

These are not great numbers. We’d want to have millions in the pool. Even if we went 100% PCV, a meager 500k will not go far.

That leaves us with option 5 & 6. Option 5. is to use T rewards. If we direct T rewards to the stability pool, we will be renting liquidity. Meanwhile we can direct 100% of the profits from lending into PCV. Over time, the PCV will increase in value until a point where we no longer need to issue T rewards.

Option 5. appears like a very flexible and simple option to bootstrap the protocol. But what about option 6.?

The treasury is going to need a 1-2 year runway secured in stablecoins to be able to pay operating expenses regardless of market conditions. This amount can be held as thUSD and placed in the pool (PCV). Funds in the stability pool is very flexible, T DAO can easily draw from the funds when needed. This makes the capital both productive and self-reinforcing. What better stablecoin to store funds in than our own?

How exactly those funds are raised can be debated. Selling T for thUSD on the market, or through some kind of bond mechanism to quickly raise funds with small rebate for purchasers. Amounts are also up for debate, but I will suggest to implement a combination of option 5 & 6.

Numbers

I’m going to make some assumptions here:

• 10% inflation in T
• Price is $0.10 per T
• Target 20% APR

If we allocate 10% of rewards (1% of inflation) to bootstrap liquidity for Threshold USD we can expect to reach $50M in the stability pool.

1% of yearly inflation is worth $10 million. LUSD is considered a safe return, it carries minimal risk compared to other yield farming pools. In fact, liquity has stabilized in the area of 15-25% APR and been there for months.

If we aim for 20% APR we can expect to raise $50 million in the stability pool. Liquity Protocol currently has $853M in stability pool and $1283M LUSD supply. But these numbers are skewed because of the LQTY rewards being so high. It’s not necessary to have that much LUSD placed in the pool for the protocol to survive.

In fact, during the first stress test of liquity only about 93.5M LUSD was offset against the stability pool with 1340m LUSD outstanding. That’s 7%. Some were also recovered through recovery mode. Unfortunately there’s no data on that, but I’ll round it up to 10%.

In other words, $50M in the stability pool should allow for 10x the amount of loans, about $500M. That is plenty of liquidity.

The PCV will grow slowly, for every 1B of loans at least $5M is added to it. But if we can bootstrap some liquidity by having the treasury place some or all of its stablecoin portfolio in the pool we will be able to reduce the amount of T rewards allocated.

E.g if we have a 2 year runway of $25M, placing that in the pool will reduce the T required to half, only 0.5% of total inflation.

These are ballpark numbers and assumptions, I’d be delighted if any statistics/math wizard can crunch the numbers better. But it’s a starting point, and if we’re not happy we have the flexibility to adapt the parameters using the DAO.

My suggestion

1. 100% of profits into PCV from day 1
2. 100M / 12 = 8.33M T rewards allocated per month to the stability pool (minus whatever treasury puts in the PCV.)
3. Gradually decrease T rewards as the PCV grows in size
4. Once PCV has grown large enough to support the platform with zero T rewards we can introduce the next phase, which is T-buybacks
5. T-buybacks will slowly and gradually increase in percent, e.g it could start as 10% T-buybacks and 90% into the PCV, but gradually increase until T-buybacks are 90-100% of the profit distribution.

T-buybacks can become 100% of the distribution once the PCV is large enough, because the PCV in normal circumstances never will decrease. In fact, we can be expect the PCV to increase even without profits as long as liquidations occur.

During times of high growth it may be necessary to allocate some profits to the PCV anyway in order to keep up with the growth because more positions opened means more can be liquidated during a black swan and that requires more funds in the stability pool. For this reason, we’ll likely never do 100% T-buybacks during growth phases, but stop at whatever makes sense, e.g 90-95%. The % can be voted on by the T DAO.

In summary, replacing the LQTY token results in a much better distribution of profit into useful purposes that can improve the protocol rather than drain it. T-buybacks will take the place of LQTY in times when the PCV no longer need to be funded. T rewards is a temporary stand-in for LQTY in the first months to bootstrap the protocol, with the intention that PCV will take it’s place as soon as possible.

Personal opinion / disclaimer
I’ve been a user of Liquity since inception. I’ve have funds placed in the stability pool. One thing I find particularly amazing about Liquity is that as a depositor in the stability pool, you end up “buying dips” at the most opportune time - that is, when people are getting liquidated.

If you’ve been using DeFi as the price is moving rapidly you know that is difficult due to explosive transaction fees on Ethereum, but when you’re in the stability pool you’re buying ETH at discount without having to spend any money on fees. Imagine having our treasury fund in the stability pool, just gathering rewards effortlessly while simultaneously supporting our own protocol.

Technically you have to withdraw the ETH and sell them on the market yourself, but B.Protocol has developed a system that does this job automatically.

Next steps

While T DAO is not launched yet, I believe we can already start the discussion of this proposal. Most, if not all of it can already be developed and be ready by launch. This is a fork, so the amount of development is not expected to be a lot. But new concepts like PVC and auto-compounding (like B.Protocol) might require some code.

I’m looking for feedback, which ideas are good, which is bad?

Some questions for the community:

1. How much T to allocate to the stability pool

2. How much can the treasury place in thUSD

3. What are your thoughts on PCV vs rented liquidity? Is everyone on board with PCV?

4. Should the protocol’s immutability be preserved? Liquity cannot be upgraded, it has two oracles, one is backup. If we want to add the option of upgradability we should debate a timelock period.

5. What should be the name, do we put this under the same banner as Threshold Network or do we separate the two? I came up with Threshold USD (thUSD) but we can discuss alternatives.

We will also have to consider assigning some liquidity to thUSD pairs on curve, uniswap or similar, but that can be its own proposal.

If anyone is completely opposed to this idea, let your voice be heard. I think this can be a very useful addition to the Threshold Network ecosystem.

This is a soft-proposal. Most parameters can be adjusted by the T DAO as we go along. Quotes for the programming work is something that will have to seek out before we proceed with the final proposal and vote.

[ramaruro1]

This is a very well thought out proposal and needs some good debate. Thanks for sharing!

I’m a user of Liquity since inception and I like most of its features, I think it is a great model for leveraging your collateral in a decentralized way.

Given somewhat failed previous efforts to position TBTC V1 as collateral in major protocols (eg MakerDAO, AAVE did not accept it), this approach would bypass the need to have other protocols accept TBTC V2 as collateral and accelerate adoption.

There is one major considerations if going this route:

thUSD needs to have deep liquidity in Curve so that you can then move to any other major stablecoin and/or protocols from there on (eg thUSD to DAI, LUSD, MIM, USDC, etc)

This is extremely important to maintain peg. Other minor stablecoins (eg DOLA, USDP) have suffered due to thin liquidity in Curve.

Also a significant amount of available collateral needs to be available.

The two main destinations for TBTC V2 in this scenario would be:

• Curve: TBTC in a meta Pool with other wrapped BTC varieties
• Collateral for thUSD

With this two major uses you can access most other protocols at least indirectly.

[Agoristen]

@ramaruro1

thUSD needs to have deep liquidity in Curve so that you can then move to any other major stablecoin and/or protocols from there on (eg thUSD to DAI, LUSD, MIM, USDC, etc)

This is extremely important to maintain peg. Other minor stablecoins (eg DOLA, USDP) have suffered due to thin liquidity in Curve.

I’m looking at LUSD pool at curve, at the moment these are the stats:

• LUSD: 56,885,015.89 (48.32%)
• 3Crv: 60,833,517.47 (51.68%)
• LUSD+3Crv: 117,718,533.36

APY: 0.48% → 1.19%

That’s extremely cheap capital, but it was built with higher rewards originally. Now it has dropped because (according to Kolten on Liquity discord):

You basically pay to increase CRV emissions on a Curve pool by bribing voters on the gauge votes.
That’s the primary reason why LUSD’s Curve APY has dropped a lot — we haven’t paid bribes.

Besides from assigning T to pools, it might become a consideration for the treasury to own CVX and vote/bribe with it, not just to get liquidity for thUSD / stable pair, but also tBTC. It might be an alternative to spending T.

I can’t come up with any concrete plan for these pairs as I’ve not studied it closely enough, but certainly an important aspect to secure a minimum liquidity.

What I will say though (as one of the earliest users and arbitragers of LUSD) is that it’s not absolutely vital to have a pair on curve. LUSD started as uniswap only. The peg is built so that arbitragers are incentivized to set a floor. If price drops below $0.99 it becomes profitable to redeem LUSD for the underlying collateral. It will certainly be more unstable, price was fluctuating at times between $0.9-$1.1 but the peg is sound and stability will regardless increase as more diverse usage takes hold.

[Agoristen]

I had a chat with @ben and another interesting idea came up. Let’s call it option 7.

This option enables us to bootstrap Threshold USD for free.

Instead of assigning funds into PCV by selling T or funneling T rewards into the stability pool, we could simply give the PCV a special permission to mint thUSD without collateral and place the thUSD into stability pool.

E.g: PCV mints $100M thUSD and place it in the stability pool.

Creating thUSD out of “thin air” is fractional reserve you might argue, but the minted thUSD is accounted for: all is located in the stability pool and could immediately be repaid.

During liquidation events some of the thUSD in the pool will be replaced with tBTC, but it’s expected that each liquidation results in a gain of up to 10%. If the pool immediately sell tBTC for more thUSD it will be possible to retain full backing. Furthermore, as the PCV grows when loans are taken, there will soon be a buffer of several % that results in “overcollateralization”.

This is uncharted territory, maybe it’s a terrible idea for some reason? I’d like to hear peoples thoughts.

A possible issue with a large PCV that eats all liquidations is that there may be times when the liquidity to dump tons of tBTC for thUSD is not sufficient. In those times it might be required to either hold on to the tBTC (price-risk = bad) or dump them for other stablecoins, and as soon as markets are stabilized exchange to thUSD. This might be the auto-compound feature of B. Protocol with modifications.

A PCV minted out of thin air could be great for bootstrapping protocol, but ultimately, the stability pool does carry some degree of risks. There are many things that could go wrong. Main issue is selling tBTC for thUSD if there’s a massive black swan liquidation event where liquidity runs out that might result in under-collateralization and therefore lack of trust in the protocol. Those are extreme events, but not impossible. While they might be mitigated in various ways (E.g PCV owning liquidity in tBTC/thUSD pairs) I would say that the goal should still be to build the PCV with profits and gradually decrease the thUSD minted out of thin air until it reaches 0 to become a “risk-free” protocol.

[maclane]

I quite like this proposal. It creates demand for tBTCv2, a strong revenue stream + PCV for Threshold, and thUSD is interesting in its own right as an alternative to centralized stablecoins (which seem to me one of the largest existential threats to the ecosystem).

@Agoristen

it might even be that stability pool and coverage pool can be combined for maximum capital efficiency.

These are ballpark numbers and assumptions, I’d be delighted if any statistics/math wizard can crunch the numbers better.

+1 on combining the coverage and stability pools for capital efficiency , but here be dragons. It might be worthwhile engaging someone like Gauntlet to crunch the numbers and help us better understand the conditions where it would fail.

@Agoristen

I will suggest to implement a combination of option 5 & 6.

What are your thoughts on PCV vs rented liquidity? Is everyone on board with PCV?

I’m +1 on leaning heavily into PCV as early and as often as we can, especially in the current market. I think the bootstrapping mechanism you describe in Option 7 is possible right now, but that can change quickly. I’m provisionally +1 as long as we’re working towards paying down the fractional reserve but I need to think about it some more.

[Agoristen]

Self-bootstrap

• T DAO owns the PCV and can vote on actions
• PCV is given special minting privileges in Threshold USD - it can mint unlimited thUSD without collateral, but with three caveat:
  1. The minted thUSD can only be placed in the stability pool
  2. No funds can be withdrawn from the PCV while there is outstanding debt - the loan must first be repaid in full
  3. As long as there is outstanding debt, the % of profits directed into the PCV can never decrease - only increase
• To bootstrap the pool, PCV mints $100M thUSD and deposits into the stability pool immediately on launch
• 100% of profits are directed to PCV on launch, this amount cannot be decreased until the loan is repaid

The lock-in guarantees that debt repayment will happen before profit can be distributed to the DAO:

Profits from lending/redemptions will be sent to the PCV as long as the debt is not repaid. This guarantees a steady stream of income to the PCV (and thus the security and faith in the Threshold USD Protocol). If for some reason the protocol becomes under collateralized, it means the debt cannot be repaid in full and the PCV will accumulate until such time that the protocol is once against overcollateralized.

Liquidations results in thUSD being drawn from the stability pool in exchange for the collateral (tBTC). The PCV should auto-compound tBTC into thUSD. To compound, the PCV must sell tBTC for thUSD. An automated rebalance algorithm has been developed by B.Protocol, see the Whitepaper (Section 3. for description of Rebalancer).

While the exact mechanisms implemented here are beyond my expertise, B.Protocol has implemented the rebalancer for Liquity Protocol:

Liquity User Guide

I’ve created my own rough overview of how I imagine the PCV can auto-compound, it will be up to the developers to decide how B.Protocol (fork or implementation) can fit into this diagram (if at all). But I’ve added a few extra security features, such as the use of other stablecoins temporary in times of high stress and large liquidations.

PCV = Protocol Controlled Value
Stability Pool = Pool where anybody can deposit thUSD
Threshold USD = The protocol
thUSD = The stablecoin issued by Threshold USD

PCV can own:

• thUSD deposit in the stabiliy pool
• tBTC / Claimable tBTC in the stability pool (from liquidations)
• LP tokens, e.g when selling tBTC to thUSD in Uniswap
• Stablecoins (LUSD, DAI, USDC, etc)

T DAO is owner of PCV

T DAO can vote on following actions:

• Mint thUSD with zero collateral. The minted thUSD MUST be placed in Stability Pool
• Repay thUSD debt using funds from Stability Pool
• Change % of profits going into PCV
• Change slippage % (?) for trades (2% in this example)

T DAO cannot:

• Withdraw from PCV before outstanding debts to Threshold USD is repaid in full.
• Decrease % of profits going into PCV if there are outstanding debts

Black Swan Risk

For every 1 billion of loans/redemption, a minimum of $5M profit is generated and added to the PCV (assuming percent to PCV is set to 100% - as it should, early on). With success of the protocol, the buffer will increase. E.g 2 billions of loans taken out will result in minimum $10M profit. With a $100M bootstrap, that’s 10% buffer. As the buffer grows, the less risk of under-collateralization during a black swan event. For comparison, Liquity has so far generated a revenue of more than $20M since launch in April, however that amount does not include liquidation rewards. Threshold USD with PCV will also gain additional revenue from all liquidations to further boost the PCV.

In the case of a black swan event early on (before there’s sufficient buffer) and where the protocol becomes under-collateralized, the protocol will recover over time with continued usage of the protocol.

A black swan event could happen in the following way:

1. $100M thUSD is minted and placed in the stability pool
2. Price of BTC drops (a lot, and fast)
3. The drop causes $100M thUSD worth of collateral to be liquidated quickly - the PCV runs out of thUSD and holds only tBTC
4. Because of the liquidation penalty of ~10% the tBTC is worth approximately $110M, the protcol is overcollaterialized by ~10%
5. There’s not enough liquidity for the PCV to exchange $110M worth of tBTC to thUSD instantly
6. While the PCV is waiting for liquidity to sell tBTC the price of BTC continues to drop
7. The bitcoin drop continues to a point where the $110M worth of tBTC is worth less than $100M
8. In this case, the protocol will be underwater (debt is higher than PCV value - and since PCV has minted thUSD out of thin air, Threshold USD is technically “insolvent”).

Options under a black swan events are:

1. Sell tBTC at a loss for thUSD - we would need to define a maximum acceptable slippage / loss %. This will lock in the loss and prevent further downside.
2. Wait for price to recover to liquidation price and sell with ~10% profit
3. Wait for price to recover to break even and sell at 0% profit
4. Sell tBTC For other stablecoins: LUSD, DAI, USDC, USDT, TUSD, MIM etc - and then once price has recovered sell those stablecoins into thUSD

No matter what option is chosen, it is expected that the under-collateralization will decrease over time due to the following reasons:

1. Each new liquidation still yields ~10% profit
2. Loans/redemption profits (0.5%) is sent to the PCV
3. The debt is locked in USD. Due to inflation in USD and general uptrend in BTC, it’s expected that the debt will become easier to pay over time. Still, a bear market could temporarily cause the protocol to be severely under-collateralized

If a panic sets in when thUSD is considered “insolvent”, thUSD may drop in price, the PCV can then buy thUSD on discount using the tBTC, potentially fixing the under-collateralization and profiting at the same time.

However I don’t believe a small under-collateralization is going to have much, if any impact in reality. There are several algorithmic stablecoins that are technically insolvent today and they manage to maintain their peg (e.g Terra USD).

The crypto industry seems very capable of absorbing temporary debt. There have been examples such as exchanges issuing debt tokens and being able to continue operations despite being insolvent (e.g Bitfinex LEO).

Conclusion:
The lock-in guarantees that debt repayment will happen before profit can be distributed, and will build confidence in the protocol. If the PCV allocated percent is not 100% during a black swan event, the DAO can increase this percent to boost confidence in the protocol and increase repayment of debt (maybe this can even happen automatically?).

Buffer will continuously accumulate with usage of the protocol and this risk should become a non-issue over time.

I’m beginning to like this idea a lot. It will allow us to bootstrap Threshold USD while spending very little, or zero T.

[mhluongo]

Really interesting idea! The fact that we have a “no $T” go-to-market strategy here and can leave the T supply as a true buyer of last resort is especially exciting.

Adding an architectural clarification on tBTC v2 that I think might make this even more compelling: we’ve split the v2 architecture into two discrete components, the “bridge”, and the “bank”.

The bank is responsible for all tBTC minting and debt management. It treats tBTC as the synth that it is, built atop the bridge.

The bridge is responsible for managing stakers and wallets, tracking BTC deposits and withdrawals, and other details of the bridged chain. It exposes an API to the bank that tracks depositor’s BTC balances, and allows the bank to lock, unlock, and in some cases seize them.

The reason we made that choice (outside of good separation of concerns) is exactly for applications like this. thUSD could be built directly atop the bridge, allowing BTC depositors to get thUSD loans against their BTC balances, as well as accepting tBTC as 1:1 collateral BTC balances.

[ben]

Such an awesome proposal.

@maclane

I’m provisionally +1 as long as we’re working towards paying down the fractional reserve but I need to think about it some more.

It could be interesting to have the PCV pay down the initial fractional reserve and then accumulate fees + liquidation margins to become an OTC buyer (with a volatility check to avoid whales exploiting price oracles or maybe treasury guild approved) and seller (with a 12 month staking requirement) of T

[ramaruro]

This might work, but is a very risky idea. I see this somehow similar to what happened with the MochiINU debacle (although it is not the same), where they printed money out of thin air with the intention to pay it back later. It collapsed very quickly. They did some dirty tricks that caused the collapse, so it is not the same, but it can definitely be perceived as the same.

I am cautiously not in favor of that approach, needs more debate for sure.

[Agoristen]

Liquidity Pools
Liquidity is important to make thUSD useful as a currency. There should be a low-slippage pair against other stablecoins (e.g a curve thUSD + 3pool (DAI, USDC, USDT) pair) to enable Threshold USD’s ease of access to the DeFi ecosystem.

Additionally, if we go for the self-boostrap method and/or a strong PCV in the stability pool, liquidity between thUSD and tBTC becomes important because the PCV will be exchanging tBTC into thUSD often, and at times with high volume.

One option would be to send liquidity incentives to a thUSD/tBTC pair, but such pair would result in impermanent loss for liquidity providers. This makes the cost of being a liquidity provider high, and will require high rewards.

The solution to cost-effective liquidity is, in my opinion, to remove the impermanent loss risk.

Instead of a thUSD/tBTC pair we could have the following pairs:

1. tBTC/WBTC/renBTC (curve)
2. thUSD/stablecoins (curve)

The PCV can use a router to trade tBTC → WBTC/renBTC → USDT/USDC/DAI → thUSD

That way we can reward liquidity without impermanent loss risk. That risk is carried by whoever is in the stablecoin/WBTC pair (e.g on uniswap). By doing so, less T rewards will buy us more liquidity.

While we may be able to spend 0 T on the bootstrap process itself, we should make sure there is liquidity on these two pairs.

But the tBTC/WBTC/renBTC pair does not need to be a part of this proposal, T DAO is going to reward this pool independently of Threshold USD because liquidity is important for tBTC by itself.

Therefore the one and only pool that this proposal really needs to incentivize is thUSD/stablecoin pool.

Whatever incentives we assign to this pool will be the real cost of Threshold USD. And maybe these pools (given that they do not have impermanent loss) could even be filled with funds from Threshold Network’s own PCV at some point.

[Agoristen]

What exactly do you think is risky? These situations are quite different, but we absolutely need people punching holes in the idea. In fact this whole proposal needs more scrutiny. So if you have anything specific please do tell.

[kins]

@Agoristen

put this under the same banner as Threshold Network

1-put this under the same banner as Threshold Network
2- 30% of T allocated to stability pool

[Sloopjohnb]

Not sure how you are thinking about this proposal is similar to the Mochi Inu actions which were more a purposeful Governance attack/Curve slanting taking advantage of a token disparity. Which if you really look at what was done with the Mochi Inu that person has been noted as a ‘scummy or scamy’ action by a highly questionable actor in the crypto space.

What was being called for here is a long term commitment with risks as noted based on price drops of overall BTC valuations. Though with the market already have taken a downturn it might be worth again considering this proposal. I would ask that the Treasury Guild again look at this proposal as a long term. And from a coding side should be prioritized via a move toward a formal vote.

Haven’t seen any further discussions since December so has this simmered for a month without further commentary? But didn’t want to see such a long term proposal which could benefit the new Threshold Network go to the wayside or get deprioritized.

[ben]

Hi, the conversation has been ongoing in Discord, there is a Threshold USD Task Force thread in the integrations guild.

If you go to the #claim-a-role channel you can react to the message to unlock the integrations guild and the link above will take you to the start of the thread.

[Sloopjohnb]

will do… thank you Ben