Wrapped.com and xERC20: How Tokensoft Built the Infrastructure for Cross-Chain Assets

When Tokensoft launched wrapped.com in early 2021, it was solving a problem that would only grow more acute as the blockchain ecosystem fragmented across dozens of competing networks: how do you take a valuable asset from one chain and make it natively usable on another, without compromising custody, compliance, or the integrity of the underlying supply?

The answer Tokensoft built — from the ERC-20 contract architecture to the custodian relationships to the on-chain oracle infrastructure — became the foundation for a new product category, and ultimately for a new token standard that Tokensoft co-created with Connext: xERC20 (EIP-7281).

What Wrapped.com Is

Wrapped.com is institutional infrastructure for creating ERC-20 representations of assets from other blockchains. Every wrapped token issued through the platform is:

• Backed 1:1 by the underlying asset held with a regulated, institutional-grade custodian
• Freely usable in DeFi — on Ethereum's lending protocols, AMMs, and yield platforms — without requiring the holder to leave Ethereum
• Redeemable at any time: send the wrapped token to the burn address, receive the underlying asset from the custodian

The model is simple at a conceptual level. The execution is where the complexity lies — and where Tokensoft's institutional background made the difference.

Assets Launched

Tokensoft's Wrapped platform has issued and managed the following cross-chain assets:

wXRP — Wrapped XRP on Ethereum

wXRP brings XRP's liquidity to Ethereum DeFi. Underlying XRP is held in institutional custody with Hex Trust — a licensed custodian in Hong Kong regulated under the Securities and Futures Ordinance. Each wXRP is redeemable 1:1 for XRP at any time. wXRP has been listed on Ethereum DEXs and used as collateral in DeFi lending protocols, bringing XRP's $30+ billion market cap into the Ethereum liquidity ecosystem for the first time.

The wXRP intellectual property — including the smart contracts, custodian agreements with Hex Trust, the minting/burning authorization framework, and the regulatory compliance architecture — is currently being valued by JS Held for a strategic sale. Luke Judges of RippleX (Ripple's developer arm) has engaged as the prospective buyer.

wFIL — Wrapped Filecoin on Ethereum

Tokensoft launched wFIL in partnership with Swarm, a regulated custodian. The announcement in early 2021 made wFIL the first Filecoin ERC-20 token — allowing FIL holders to participate in Ethereum DeFi without selling or bridging their underlying Filecoin holdings. Swarm holds the underlying FIL; Tokensoft's contracts govern the mint and burn.

wCELO and wCUSD — Wrapped Celo Assets

Celo's native assets, wrapped for Ethereum DeFi participation. Marek Olszewski, Celo's co-founder and cLabs CTO, cited Tokensoft's infrastructure directly when commenting on the Tokensoft Distribution launch: "We're excited to see more DeFi projects launch on Celo. With Tokensoft V2, DeFi projects can easily launch and distribute their token natively on Celo."

xBTC — Wrapped Bitcoin on Stacks

xBTC is Tokensoft's wrapped Bitcoin product for the Stacks blockchain — a Bitcoin Layer 2 that enables smart contracts settled on Bitcoin. xBTC allows BTC to be used in Stacks DeFi applications without leaving the Bitcoin security model. Current supply: 37.3 BTC in active circulation, backed by the corresponding BTC vault. The Stacks Foundation has contracted with Tokensoft to maintain the xBTC system infrastructure.

cBTC — Wrapped Bitcoin on Celo

An additional wrapped Bitcoin product deployed on Celo, bringing BTC into the Celo DeFi ecosystem. Current supply: 2.44 BTC. The cBTC smart contracts and custodial framework parallel the xBTC architecture.

The Compliance Architecture

What distinguishes Tokensoft's Wrapped products from informal bridge-based wrapping solutions is the institutional compliance architecture underlying every token:

Role-Separated Smart Contracts

Every Wrapped token contract maintains three distinct privileged roles, held by separate cryptographic keys:

• Owner — The issuer entity (Tokensoft). Can add or remove Minters and Burners, upgrade parameters, and manage administrative functions.
• Minter — The authorized minting key. Can mint new wrapped tokens when the custodian confirms receipt of underlying assets. Key is rotatable without disrupting the Owner or Burner.
• Burner — The authorized burning key. Can burn wrapped tokens when a holder requests redemption and the custodian is instructed to release underlying assets.

This separation ensures that a compromise of any single key cannot enable unauthorized supply inflation — the Minter key alone cannot burn tokens or change role assignments, and the Owner key alone cannot mint. Tokensoft documented a complete key rotation protocol for migrating any of these keys without service interruption.

Multi-Signature Control via Knox

Minting and burning operations for Wrapped assets are controlled through Tokensoft's Knox custody wallet — the multi-signature, air-gapped signing system described in our previous piece. The custodian-to-blockchain workflow is: custodian confirms receipt of underlying asset → Knox multi-sig approval threshold is met → Knox compliance pre-check verifies the mint is permissible → Ledger device signs the mint transaction → tokens appear on-chain. The private keys authorizing supply changes never touch a networked device.

Market Making Infrastructure

Tokensoft built and operated a market-making strategy to maintain price parity between wrapped tokens and their underlying assets on DEXs:

• If wXRP trades below XRP: buy wXRP on the AMM with USDC → unwrap via the redemption contract → sell XRP on a centralized exchange. Supply decreases, price recovers.
• If wXRP trades above XRP: buy XRP on a centralized exchange → deposit to custodian → mint wXRP → sell on AMM. Supply increases, premium collapses.

This arbitrage loop is what keeps the peg tight. Without it, wrapped assets drift from their underlying value. Tokensoft's documentation of this strategy is part of the IP package.

xERC20 (EIP-7281): The Next-Generation Standard

By 2022, the multi-chain proliferation created a new problem that Tokensoft's Wrapped model didn't address: canonical token fragmentation. A project that launched on Ethereum might find versions of its token bridged to Arbitrum, Optimism, Polygon, and Base — by different bridges, with different security models, backed by different liquidity pools. Users holding "USDC on Arbitrum" might not be holding the same canonical USDC that Circle issues. If any bridge was exploited, it could mint unbacked tokens and collapse the token's value across all chains simultaneously.

Tokensoft and Connext co-created xERC20 (proposed as EIP-7281) to solve this. The core innovation: rate-limited bridge minting.

How xERC20 Works

Token issuers deploy an xERC20 contract — a token that can be minted and burned by authorized bridges. Each bridge is assigned a mintingMaxLimit: the maximum number of tokens it may mint in any 24-hour rolling window. Limits replenish automatically over time as the window expires. If a bridge is hacked and an attacker attempts to mint unbacked tokens, they are capped at the bridge's daily limit — not the entire token supply.

The issuer retains full control: they can add bridges, remove bridges, and adjust limits at any time. No bridge has unconditional minting authority. No single bridge failure can inflate the entire token supply.

The Lockbox

For projects with an existing ERC-20 on Ethereum, the XERC20Lockbox provides a 1:1 conversion point:

• Deposit canonical ERC-20 → receive xERC20 at 1:1
• Deposit xERC20 → receive canonical ERC-20 at 1:1

This is the entry and exit point between the canonical supply on Ethereum and the cross-chain xERC20 representations. Users on Arbitrum or Optimism hold xERC20 — a representation of the canonical supply — rather than a bridge-specific wrapped version of uncertain provenance.

Factory Deployment

The XERC20Factory deploys xERC20 contracts deterministically using CREATE2, producing the same contract address on every chain. This is foundational for trustless cross-chain verification — a counterparty on Arbitrum can verify they're holding the same token as a counterparty on Ethereum by checking the address.

The First Cross-Chain Airdrop

Tokensoft used xERC20 to build cross-chain airdrop-as-a-service — and deployed it in production for the first time with the Connext NEXT token airdrop in September 2023. Approximately 1,000,000 registered participants received their NEXT token allocations on the chain of their choice — Polygon, Arbitrum, Optimism, or Gnosis Chain — without bridging, without slippage, and without any cross-chain transaction initiated by the recipient. Tokensoft's platform minted xERC20 NEXT directly on the destination chain. The recipient just connected their wallet and claimed.

This was the first time any airdrop had been delivered natively across multiple chains simultaneously. It validated the xERC20 architecture in production at a scale that no prior cross-chain token system had achieved.

The IP Portfolio

Tokensoft's Wrapped and xERC20 IP package includes:

• Smart contracts for wXRP, wFIL, wCELO, wCUSD, xBTC, cBTC — production-deployed, audited, with full compliance architecture
• The xERC20 reference implementation (co-created with Connext), including XERC20, XERC20Lockbox, XERC20Factory, OptimismMintableXERC20, and LockboxAdapterBlast
• Custodian relationships and legal agreements (Hex Trust for wXRP, Swarm for wFIL)
• Key rotation protocol documentation for minter/burner/owner address migration
• Market-making strategy documentation
• Live BTC custody: 37.3 BTC (xBTC on Stacks) + 2.44 BTC (cBTC on Celo) — approximately $2,821,755 in active custody as of writing
• The wXRP IP is under active third-party valuation as part of Tokensoft's IP portfolio review