An Update on tBTC’s Launch

Launched with unprecedented security measures in place and ready to be used at, tBTC is fully audited and open-source.

tBTC, which lets Bitcoin holders safely access Ethereum DeFi apps, is live and ready to be used now on A project of Keep, Summa and the Cross-Chain Group, tBTC now lets you safely and simply exchange your BTC for TBTC, an ERC-20 token that can be used on DeFi platforms, at a rate of 1:1.

Each TBTC token is fully backed and matched by at least 1 BTC held in reserve. tBTC is trustless, using a random beacon to select “signers” who have responsibility for the deposited BTC. You can convert TBTC to BTC, and vice-versa, whenever you want, with no intermediary needed to sign off. And it’s simple: it only takes three easy steps for people to mint TBTC on and track their Bitcoin.

tBTC is built on the Keep Network , and as of launching this week already has 24.21M USD locked in the network (22.69M USD in KEEP, 1.39M USD in ETH and 0.26M USD in BTC). We’ve decided to launch slowly and safely with a 9 week graduated cap, currently the cap is at 100 BTC but will rise to 250 later this week. See the full schedule here 4. Future plans for tBTC include pointing at least 5% of the KEEP supply at various liquidity rewards.

Nearly 60% of the total crypto market cap is currently held in BTC. Tapping this liquidity and making it possible to use Bitcoin in DeFi apps will be crucial to the long-term growth of the crypto economy. And it must be done right: for crypto to succeed in offering a decentralized, transparent, fair alternative to the existing financial system, any Bitcoin-Ethereum bridge must be safe and reliable.

With this in mind, tBTC has been designed with the highest standards of security and usability. The project uses threshold ECDSA, which is audited and in use on Binance among other top wallets and exchanges. And at launch, Keep has provided protections via Nexus Mutual so users can have high confidence their funds will stay safe.

Below are further details on tBTC’s launch and its architecture.

tBTC is tested and audited

tBTC has been tested rigorously and has undergone an unprecedented three audits. tBTC concluded its first security audit, by ConsenSys, in March. In June, we concluded a second audit by Trail of Bits, and in August we completed a new Bitcoin audit.

The audits to date have included an aggressive focus on the Go clients in the network as well as the smart contracts in the system. The Trail of Bits audit also focused on expanding and automating more integration and system tests for tBTC, as well as adding fuzz and property testing to various components where appropriate.

We are also looking to the community to help identify and address issues. That’s why the maximum reward for the tBTC bug bounty program is now 1 million KEEP for responsibly disclosed severe vulnerabilities.

tBTC has launched with a “release candidate” model

tBTC has launched according to a “release candidate” model, in which versions of the project are deemed “ready for prime time” — but may or may not be final, based on wider user feedback. Release candidates progress from 0, to 1, to 2, onward until a candidate is deemed final and upgraded to the stable release. This structure allows us to test the system and put it through its paces in real time, on mainnet, while still maintaining laser focus on security and ensuring users’ safety. It incentivizes the best talent to test the app for vulnerabilities, which we view as opportunities to make tBTC stronger.

The alpha launch of tBTC — known as rc.0 — went live on mainnet in May after a public audit from ConsenSys Diligence. While user funds were never at risk, our team discovered an issue and immediately paused accepting new funds while the problem was addressed. rc.1 resolves the issue, and launched with unprecedented security measures in place. tBTC, which uses the highest standard of cryptography, threshold ECDSA, is fully audited, open-source, and with protections for funds.

The dApp built atop rc.1 will remain in alpha for a period of several weeks, during which there will be a supply cap. Then, it will have a beta release cut, and likely remain in perpetual beta as features are added. Over the coming months, we will continue the launch of the dApp through succeeding release candidates. In this way, through real-world testing and refinement, we believe we can ultimately deliver a project that meets the highest standards of safety and performance to bring Bitcoin off the sidelines and onto exciting DeFi platforms like Compound.

A graduated supply cap

rc.1 features a hard cap on the TBTC supply, starting at 100 BTC in the first week. Each week, the contracts will loosen the deposit restriction based on a pre-committed schedule.

For the first 48 hours after going live, there is a very low supply cap to allow for low-risk testing. The supply cap will then increase to 100 TBTC for the remainder of the first week, then go up to 250 TBTC a week later.

The supply cap will increase by 250 TBTC every week until it reaches 1000 TBTC. After that, the increase will be by 500 TBTC every week until it reaches 3000 BTC nine weeks after going live. Then, finally, a week the supply cap will be lifted to 21M TBTC (just like BTC).

If at any point a critical vulnerability is found in the smart contracts, the team will push the emergency deposit pause, and coordinate a withdrawal of funds — then redeploy the patched contracts as rc.2, resetting the cap schedule. After 6 months without incident, the team will disable the emergency pause button.

There is currently tremendous demand for BTC-ETH bridges, but we are taking a long-term view with regard to supply caps. tBTC’s graduated supply cap gives depositors and signers a measure of the ongoing risk and confidence in a system, while protecting overly enthusiastic early users from potential issues. Ultimately, we are confident that thoughtful growth is the path to the greatest long-term success.

tBTC is backed by the community

Support for tBTC has grown to more than 50 partners over the last few months. Recently, the likes of Scalar Capital’s Linda Xie, Synthetix’s Kain Warwick, TokenSoft’s Mason Borda, and Aragon’s Luis Cuende have all said they plan to use tBTC as their BTC-ETH bridge, while the newest tBTC integrations include Matcha, UMA and FalconX. tBTC has also received $2 million from supporters including IOSG and Digital Strategies in Keep’s latest fundraising as a follow-on to an $8 million round earlier this year. This strong support indicates the demand for a safe, reliable BTC-ETH bridge and the community’s confidence in tBTC.