This article is a continuation of “How One Decision Saved This Trader Thousands”, a true story about a trader who doesn’t just buy low — they trade smart, saving themselves thousands in fees.
Quick recap. In April 2025, with ETH near $1,600, a trader wants to buy the dip. Two paths:
Default DEX (AMM swap): used by most — not because it’s better, but because it’s how early DeFi DEXs were built.
Carbon DeFi (maker-style limit order): a DEX experience that puts traders in control, eliminating inherent risks and inefficiencies of the AMM.
They choose Carbon DeFi. A single limit order turns $50,000 USDC → 31.17 ETH with:
Zero slippage & 100% price certainty
Zero protocol or trading fees on execution
Full immunity to sandwich attacks
After the buy fills, they switch the strategy type to a limit sell at $5,585 USDC/ETH.
Now, four months later, they turn 31.17 ETH → 36.3 ETH in two moves — while avoiding typical AMM taker fees, slippage, and DeFi’s most predatory attacks.
Move 1: The Edit — From Plan to Exit
On August 27, 2025, 31.17 ETH is available to buy on Carbon DeFi at a price of $5,585. The trader decides to change their sell price. They don’t close or redeploy — they edit the live onchain strategy, same way they previously edited the strategy type (buy → sell).
The play by play:
Edit: Sell price $5,585 → $4,600 USDC/ETH on August 27.
Execution engine: Carbon DeFi’s built-in solver sources liquidity from major DEXs chainwide to fill their order.
Fills: 15 executions, each exactly at $4,600
Outcome: 31.17 ETH sold for $143,395.82 USDC
Performance vs. $50,000: 2.87x growth factor (+187% growth rate)
* Side note — what makers can adjust on Carbon DeFi, anytime:
Flip strategy type: Buy ↔ Sell, Limit ↔ Range ↔ Recurring ↔ Concentrated Liquidity, etc.
Adjust price: Quickly adjust the prices you choose to buy and sell your tokens, without canceling orders, withdrawing funds, redepositing funds, or creating new orders.
Change strategy size: Add funds, or withdraw partial/full unfilled funds.
Pause: Temporarily makes funds unavailable to trade against.
Unpause: Reactivate trading at the maker’s desired price points.
Move 2: The Buy Low Re-Entry
The play by play:
Edit: Strategy flipped to buy at $3,949.99 USDC/ETH on September 22.
Execution engine: Carbon DeFi’s built-in solver sourced fills from chainwide liquidity
Fills: 9 executions beginning Sep 25
Outcome: $143,395.82 USDC → 36.3 ETH (spent $143,384.64, ≈$11.18 USDC left)
Asset delta: 31.17 ETH → 36.3 ETH = +5.13 ETH
ETH performance: 1.165× growth factor (+16.46% growth rate)
Timeline at a Glance
Apr 7: Creates a limit order on Carbon DeFi with 50,000 USDC to buy ETH @ $1,604.05
Aug 27: Adjusts the strategy to sell ETH @ $4,600, resulting in $143,395.82 USDC
Sep 22 → Sep 25: Adjusts the strategy to re-buy ETH @ $3,949.99, resulting in a total of 36.3 ETH (+5.13 ETH)
Where They Stand Now
Our trader didn’t just rebuy their ETH, they added an additional 5.13 ETH, worth $21,187 at $4,130 (the current market price at the time of writing).
That single decision is ≈ +42.4% of the original $50k (1.42x growth factor) in additional unrealized profit.
Position snapshot
Holdings: 36.3 ETH (vs. 31.17 ETH before the re-buy)
Portfolio value: ≈ $149,920
Since $50,000 start: ≈ 3x growth factor (≈ +200% growth rate)
Cost Comparison: AMM Taker vs Carbon DeFi Maker
If this trader had done the same three legs as a taker on a traditional AMM/aggregator UI, they’d typically face pool fees + UI fees on each trade. Using the industry-standard ranges (pool: 0.10–1.00%; UI: ~0.25%) and the actual notionals from this story:
Trades
Initial Buy: $50,000
Sell: $143,395.82
Re-entry Buy: $143,384.64
Fee scenarios across all legs
(Not including slippage and loss from MEV sandwich attacks)
Low fee (0.10% pool + 0.25% UI = 0.35%) → $1,178.73
Typical fee (0.30% pool + 0.25% UI = 0.55%) → $1,852.29
High fee (1.00% pool + 0.25% UI = 1.25%) → $4,209.76
Carbon DeFi (Maker)
$0 protocol or trading fees on execution
No slippage
Full sandwich-attack immunity
(Creating the strategy + edits cost < $10 total at current Ethereum gas prices. On AMMs you’d also pay network gas per swap — plus taker fees, UI fees, and slippage.)
Fees are the visible costs of trading on AMMs. The hidden one is MEV sandwich attacks.
Sandwich Attacks: One of DeFi’s Most Predatory Attacks
What it is:
A bot buys before your visible swap and sells after it in the same block, forcing your trade to a worse price and keeping the difference.
Last 7 days on Ethereum alone:
$3.5M+ extracted by attackers
9,385 victims
81 active attackers
Source: https://eigenphi.io/mev/ethereum/sandwich
Why takers get hit
Public mempool exposure: size/price visible before inclusion
Slippage tolerance: hands attackers a budget to exploit
Single-path routing: predictable AMM routes/routers are easy targets
Source: https://eigenphi.io/mev/ethereum/sandwich
Why makers on Carbon DeFi are immune — by design
Carbon DeFi is not an AMM and doesn’t rely on liquidity pools
One token per curve: each order is a single-token bonding curve, removing the two-token impact surface MEV bots exploit
Asymmetric liquidity: makers post buy-only or sell-only intent — no symmetric pool to game
No slippage parameter: orders execute only at your exact limit (price certainty)
Built-in solver system: fulfills against chain-wide liquidity, not a single pool
Result: Sandwich attack exposure: 0, always
More on sandwich attack immunity: “The Solution to One of DeFi’s Most Predatory Attacks”.
For a deep dive, see the Sandwich Attack series by Project Lead Dr. Mark Richardson and Senior Advisor Stefan Loesch here, and Mark’s ETH Belgrade presentation below.
Dr. Mark Richardson presents DEX MEV: Sandwich Attacks 101 at ETH Belgrade 2025
Takeaway
This trader shows how strategy and execution shape results using app.CarbonDeFi.xyz.
With one limit order and two edits, the position moved from $50,000 → 31.17 ETH → 36.3 ETH , +5.13 ETH more than before, worth ~$21.2k at $4,130/ETH.
The driver was structure, not luck: maker-style orders with price certainty, fulfillment via a chainwide solver, and $0 protocol/trading fees on execution for makers.
Network costs were minimal: < $10 in gas to create and edit the strategy.
Pre-set, don’t chase: Define entries/exits in advance and let the strategy work, instead of reacting to every move.
Edit in place: Flip buy ↔ sell, adjust limits, or resize without closing/recreating positions.
Price Certainty: Maker orders execute only at the set price — no slippage variable.
Reduce attack surface: A single-token curve and asymmetric liquidity (buy-only/sell-only), fulfilled across chainwide liquidity, remove AMM dynamics that enable sandwich attacks.
For traders who value strategy and predictability, a maker-first, adjustable approach can turn disciplined price targets into cumulative gains while keeping costs and exposure in check.
