Uniswap Labs opens TJAR fee-conversion tool to third-party apps, Robinhood first
Uniswap Labs opened TJAR, its Token Jar fee-conversion framework, to third-party apps. Robinhood is the first integration — Uniswap API fees settle in USDC and USDG on seven chains.
Uniswap Labs on Oct 29 released TJAR, the fee-conversion framework it originally built for the Uniswap protocol's own fee switch, as an open tool other apps can plug into. Robinhood is the first external integration and now takes the fees it collects through the Uniswap API in USDC and USDG on every supported chain. The announcement is on the Uniswap blog (blog.uniswap.org/tjar-onchain-fee-conversion-for-any-app) with developer documentation at developers.uniswap.org/docs/protocols/tjar/overview. First reported by The Block.
How TJAR works
Apps collect fees in whatever token hits the contract — any ERC-20 that users traded through. TJAR routes conversion through a competitive on-chain auction:
- An app sets the output token it wants to receive and the price it is willing to accept, denominated in that token.
- Deposited assets land in a Token Jar — one jar per app, per chain.
- Searchers compete to pay that price in the app's chosen token into a contract called the Releaser. The Releaser hands the jar's assets to the first searcher that pays in full, and the chosen token flows to the app's destination.
- The jar sets no on-chain prices; searchers decide whether to bid based on their own routing.
The Uniswap DAO can switch on an optional TJAR protocol fee. None is set today.
For the Uniswap protocol itself, the destination token is UNI and it is forwarded to a burn address — the mechanism that turns the fee switch into supply reduction.
Robinhood's integration
Robinhood routes fees from its Uniswap API integration — the venue most of its on-chain trading sits on top of — through TJAR on every chain it supports. Deposits convert as they arrive. The output tokens are USDC and USDG: USDC for the dollar legs that will likely feed back into Robinhood's custody, and USDG — Global Dollar, Paxos' consortium stablecoin — on the chains and venues where it is active.
The split between USDC and USDG was not disclosed per chain.
Numbers
| Chains live | 7 (not individually named) |
| September conversions through the Token Jar framework | > $15.3M |
| TJAR protocol fee today | 0 |
| First external integration | Robinhood |
| Output tokens for Robinhood | USDC, USDG |
| Output token for Uniswap protocol | UNI (burned) |
The $15.3M figure covers the framework's existing usage before this release — predominantly the Uniswap protocol itself. The ratio of fee flows that will now route through TJAR for third parties is a function of app integrations announced from here on; Robinhood is one.
Why this matters
Fee conversion is a line item every multi-chain app rebuilds on its own: receive fees in a long tail of tokens, convert into something treasuries can hold, pay for the gas, resist front-running on the conversion itself. Teams typically wire this to private market-maker arrangements or route through aggregators and accept the leak.
TJAR replaces that with an open market for searchers, same stack the Uniswap fee switch already uses, and settles the economics on-chain. The design choice that distinguishes it from a conventional MEV auction is the price-first mechanic: the app names the price it accepts; searchers bid by paying it. Searchers that cannot find a profitable route simply do not act, and the jar waits — the jar does not sell at a loss.
What to watch
- The list of the seven chains. The announcement did not name them; developer docs will.
- Second and third integrations after Robinhood. Fee-handling infrastructure benefits from standardization — the question is whether app teams converge on TJAR or route through their own stacks.
- Whether the Uniswap DAO moves to turn on TJAR's protocol fee. The parameter exists; passing it means governance recognizes a transferable value capture distinct from the UNI burn.
- MEV behavior: searchers compete to fulfill the jar at the app-set price; whether they also compete on timing (how long jars sit before clearing) is the thing to measure once chains and jars are enumerable.
Context
TJAR is the second time this quarter the Uniswap protocol's own machinery has been released as a product other apps can take: the week of Oct 10 v4 aggregator hooks went live on seven venues, using the hooks layer added at the v4 upgrade. Fee conversion is the next piece — and in Robinhood's case, the fee itself was already settling through the Uniswap API; TJAR is what the operator gets at the end of it rather than a new flow.