Synthetix

Havven launched nUSD on Ethereum on 11 June 2018. The design paired the stable nomin with HAV collateral, aiming to let a volatile token absorb the work of holding a dollar unit steady.

On 30 November the project renamed the network Synthetix, HAV as SNX, nomins as Synths and nUSD as sUSD. The announcement was unusually precise: nothing should happen to tokens except the name because no address changed.

That sentence ceased to describe the whole technical lineage in 2020. A proxy cutover on 10 May moved primary ERC-20 interaction to 0xC011a73e…; the old 2018 proxy became legacy. A biography that calls the rebrand a token swap is wrong, but one that says the address never changed is also incomplete.

V2 turned SNX stakers into the collective counterparty to Synth traders. Minting sUSD created a debt share, and the value of that share moved when Synth prices or trader profits moved. Weekly fees rewarded eligible stakers, while falling collateral ratios exposed them to liquidation.

On 25 June 2019 a KRW price feed carried an incorrect rate. A bot converted the mispricing into roughly 37 million sETH before exchange functions were disabled. Synthetix contacted the bot owner, who agreed to reverse the trades for a bounty; the official post then reported that service had resumed.

The episode matters beyond its dramatic nominal value. The system depended on an external price entering correctly, a concentrated team being able to stop functions quickly, and a bot operator cooperating. The related CoinYQ story follows that same incident without treating the synthetic balance as a realized billion-dollar theft.

SIP-300 replaced V2's blended debt pool with vaults, pools and markets. Vaults group collateral, pool owners allocate credit, and market profit or loss returns through those allocations. Modular risk was the point: one pool could choose markets instead of every staker inheriting the same basket.

The architecture also widened the control surface. V3's Router is upgradeable, and its own repository warns that a proxy owner could introduce selector collisions. Pool configuration, market parameters, oracle choices, collateral settings and implementation upgrades therefore remain separate powers.

Monetary policy changed in parallel. Inflation introduced on 13 March 2019 was set to zero by SIP-2043 in December 2023. That ended scheduled weekly issuance, not governance's ability to approve another mint for a different purpose.

SIP-420 tried to remove debt management from each wallet. The 2025 pool accepted legacy positions, managed sUSD and debt centrally, offered a 12-month forgiveness path and retained a seven-day exit cooldown. Later documentation opened a simpler path for new stakers without individual c-ratios or liquidation.

SIP-423 rewrote that bargain in 2026. It stopped the old linear debt burn, removed the sUSD holding requirement, returned debt-free SNX and left debt-bearing SNX with the pDAO. Continuing participants face a four-year lock plus one-year vest, while early exit requires repaying the remaining debt in full.

The same SIP suspended legacy sUSD and recorded 59,116,089 eligible units. At four SNX per sUSD it permits up to 236,464,356 newly minted SNX. Yet Phase 3's receipt contract and Phase 4's new staking contract remain marked BUILD DEFERRED. Etherscan's 581,404,223.555663177920417946 total-supply display is therefore a dated chain observation, not the final arithmetic of the plan.

Synthetix wound down L2 perpetual markets and returned to Ethereum with a hybrid design: an offchain central-limit order book matches orders while contracts custody margin and settle results onchain. The December 2025 launch began as a private beta; the May 2026 update describes mainnet perps as live, while later features remain plans.

Governance also compressed. SR-2 replaced three councils with seven Spartan Council seats and a four-of-seven signature threshold. Some seats are elected; operational seats are hired and replaceable by the elected seats. Treasury actions additionally require the Treasury Seat.

The council is not the whole machine. SR-2 leaves the pDAO validating, staging and executing upgrades, and the SNX proxy exposes an owner-controlled target and delegatecall mode. Holding SNX alone is therefore neither direct execution authority nor a legal share, deposit, fixed yield, Synth-asset title or automatic fee claim. Those benefits and risks appear only through specific staking, governance and contract paths.