The protocol lifecycle
A full timeline of a Spield position — from deposit, through earning and trading, to maturity and redemption.
Here's the whole journey of value through Spield, end to end. Everything else in the docs is detail on one of these stages.
The timeline
Stage by stage
Deposit
You deposit USDC. It's immediately supplied to the yield source and begins earning real interest. In return you receive equal amounts of PT and YT (or, via the Fixed-Rate Vault, a single receipt for a guaranteed payout).
Earn & manage (before maturity)
While the market is open, you have choices:
- Hold PT to lock in your fixed return.
- Hold YT and claim its accrued yield in USDC whenever you like — the YT keeps earning.
- Trade PT or YT on the market as your view changes.
- Provide liquidity (PT + USDC) to earn swap fees.
- Recombine equal PT + YT back into USDC to exit early.
Approach maturity
As the maturity date nears, prices converge predictably: PT drifts up to par (1.0) and YT decays toward zero. The trading market is built around exactly this path, so liquidity providers who hold to maturity face minimal impermanent loss.
Maturity
At the maturity date, the market stops trading (there's nothing left to price — PT is about to be worth exactly 1 USDC). PT becomes redeemable 1:1.
Redeem
You redeem your PT for USDC at par, and a Fixed-Rate Vault receipt for its full guaranteed payout. Any YT yield you hadn't claimed can be settled. Your position is complete.
A worked example
Say you deposit 1,000 USDC into the Fixed-Rate Vault at a 5% fixed APY for a 90-day term:
| Moment | What happens |
|---|---|
| Day 0 | Deposit 1,000 USDC. You get a receipt for a guaranteed payout of ~1,012.5 USDC at maturity. |
| Days 1–89 | Your USDC earns real yield in the background. Your payout is already locked — it doesn't change. |
| Day 90 (maturity) | You redeem the receipt for the full ~1,012.5 USDC. |
The exact figures depend on the rate and term shown at deposit time; the point is that the payout is known and fixed from day 0.
What if you want out early?
You're never locked in against your will. On the PT/YT path you can sell on the market or recombine PT + YT to exit any time. The fixed return is what you get if you hold to maturity — leaving early means taking the current market price instead.
Where to go next
- See the products that wrap this lifecycle into one-click flows → Features
- Follow a concrete walkthrough → Guides & Tutorials
- Build on top of it → Developers
Solvency
Why Spield can always pay everyone it owes — the solvency invariant, how it's enforced on every operation, and how you can verify it live on-chain.
Features overview
The complete set of Spield features — the Fixed-Rate Vault, PT/YT tokens, the yield market, liquidity provision, the cross-chain bridge, and the live solvency dashboard.