Ability to swap between ZEC <> renZEC (ERC20)

Hey there,

I represent the team behind Unstoppable wallet app, https://unstoppable.money. Recently the wallet got listed on bitcoin.org which has fairly steep requirements for listing these days.

We are among the first wallets out there to support shielded Zcash transactions. We also expect to integrate all Zcash protocol improvements as they become available.

Meanwhile, we have submitted an application for a grant, ZF Grants - Ability to swap between ZEC <> renZEC (ERC20)

Looking forward to your feedback.



This is super interesting and exciting!!

How do you imagine this feature being used? Will unstoppable also let people trade renZEC for ETH or BTC?

Will this work be designed to be used by other wallets as well, or will it be tightly coupled to Unstoppable?

One version of this feature that would be extremely useful ecosystem-wide is a library that gave users an ETH address (or QR code) at which they could deposit ETH and exchange it for ZEC. Is that the UX you were picturing?

We’re about to have a meeting, but these are my first impressions:

  1. Funding wallets like Unstoppable makes sense to me.
  2. This specific feature is cool and envelope-pushing both for privacy and decentralization, so funding it seems cool.
  3. If we’re funding this specific feature, it would be even better, and even more attractive for funding, if the work was easy to integrate in other wallets, like Nighthawk, Zecwallet, and maybe even Zbay. (And I say this as a wallet maker myself) — though again, simply funding work on Unstoppable makes sense to me too.

Also, if you have any mockups of how this would look to a user, that might be helpful? It’s alright if it’s just in the idea stage and you don’t have those yet, but if you do, it’d be awesome to see them!


Oh, and one more question: is this work the end of the project? or would there be a “phase 2”?

And if there’s a phase 2, what’s phase 2 (or 3, or 4, etc)? :slight_smile:

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@ibek congratulations on the bitcoin.org listing! They gave Unstoppable really high ratings in each category and that’s impressive. I couldn’t be happier for you because your team has been excellent to work with. I’m glad to have you in the community and I look forward to whatever the next steps may be!


Congrats on the Bitcoin.com listing and i’ve heard lovely things from everyone at ECC who worked with you all.

What do you mean by swappying? If you mean swap ZEC for Eth/other assets via RenZEC in a decentralized/permissionless way , awesome yes we need that. This would solve a number of things, especially if you made the swap transparently convert to shielded zec. Which in fact I think should be a requirement that it supports and be the default.

If you literally want to swap zec for renZEC’s ERC20 tokenized/wrapped zec, I’m not sure what this would be used for besides swapping zec for eth/USDT/dai,etc. Which again, would be awesome and we should totally do .

My (likely flawed) understanding of REN is its a platform that can issue wrapped tokens where the underlying asset (zec,btc, etc) is held by some threshold sig who’s key shares are held by some ( i assume staked/slashed) participants. They issue a ERC20 wrapped version of the asset backed 1 to 1 by their reserves of the native asset. They will let you unwrap your ERC20 zec and give you actual native zec.

The reason to focus on swapping assets into shielded via Ren is that it gives users access to the actual thing that gives zcash utility: its privacy. If you are holding wrappedZEC or transparent zec, all you get is yet another coin. Sure, it might go up, or down, or some places might accept it, but it seems to me there’s little it has going for it over say litecoin. On the other hand, if you let people get privacy via swapping their Eth/ERC20s into private transactions, there’s a unique utility proposition there. This there should be a major market for.


I think there is another advantage: access. In places where centralized exchanges are prohibited (regulatory, payment rails, banks), having access to a wrapped ZEC via a DEX allows someone to acquire it as renZEC, redeem it for ZEC and then move it to shielded storage …assuming it isn’t currently possible to redeem it directly into a zaddr. There is one CEX that I know of that is at least thinking about adding wrapped ZEC (renZEC or WZEC) that cannot currently add the native ZEC, because its an ERC20 token, which they percieve may be ok with their regulator.


Hey Ian,

Swapping ZEC for renZEC allows ZEC holders to participate in Defi, yield farming, etc. etc. Here’s an example of an incentivized pool for renZEC.

I support Unstoppable adding this “mint renZEC with ZEC” capability “in wallet”, however I want to prepare folks for the reality that uptake may be slow until congestion on the Ethereum network abates or L2rollups / Eth2 starts alleviating the gas crunch.



I’m super curious about this. How much does a full ZEC → renZEC → DAI trade cost right now, roughly? On the order of $10-$20 USD? More?

I’m really excited about this too! A universal onramp to shielded ZEC for anyone who can buy ETH!!


Right now, it depends on the day, the time, the speed, the method of exchange. I just tried to Uniswap ETH->DAI and it quoted gas fee equivalent to $122. But these tools could be super useful when the fees are negligible.

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Just to chime in as someone representing the Ren team, we would be happy to help out with the integration :+1: Just DM me or Michael Burgess on Telegram and we’ll get you sorted (Telegram: Contact @renproject)


Are the ren gas fees on the same order?

I still think this idea is really valuable, as it’s likely that ETH fees will decrease in the future, and the added privacy will be worth it to some users for transactions in the $1000 usd range.

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thanks Maximilan,
will be in touch over Telegram;)


@iBek, speaking on behalf of the ZOMG, we noted your comment on the ZFND page:

Update (Feb 12)

Upon further research we stumbled upon some blackboxes that complicate the integration. We are evaluating them now and will followup here on Monday.

We are keen to see project this happen. Please feel free to modify the grant based on your research. Let us know if you need any support from us / anyone else we can bridge you to.


@iBek let us know when you’d like us to consider this again.

If you decide to continue with this application, one thing we wanted to ask for was for you to set the milestones so that you’re paid 50% at the outset and 50% upon completion. Also, it would be great if you could answer my questions above so that we can consider your answers to those as well.

If this path turns out not to be feasible for some reason and you’d like to apply for any other Zcash-related work, we welcome that too,

Again, we’re really excited about this project and about supporting your Zcash-related work in general.

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As mentioned before feel free to reach out to us for assistance. We’ve had multiple projects integrate our SDK, it’s true though that the documentation could be better so we have one of our frontend devs improving documentation right now.

We also have a relatively new library called ren-tx that wraps around ren-js and should make integrations easier.

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@iBek Has informed ZOMG that they are withdrawing this proposal for now, with plans to re-submit at a later date.

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