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Khomenkov Yuriy — KhomDev

I build composed DeFi ecosystems in Vyper

Not five separate contracts — one interconnected flywheel. A stablecoin, ve-governance, a vault, and an intent DEX, wired together by permissionless routers that move value but never hold a key to it. Live on Sepolia, fuzzed & self-reviewed.

Passed Chainlink Developer verification — verified Cyfrin profile

4-in-1 Composed Ecosystem
Vyper Primary Language
Sepolia Live Testnet
Fuzzed Self-Reviewed · Not Audited
khomdev ~ vyper-dev.json
$cat developer.json

One flywheel, four contracts, zero keys to the money

Over Phases 3 & 4 I composed four of my Vyper contracts into a single self-reinforcing DeFi loop. Every arrow is a small permissionless router that can only move value the protocol has already released or earned — no admin reaches through, including the DEX. Everything here is live on Sepolia testnet, fuzzed & self-reviewed — not audited.

CoilFeeRouter · A SurplusSplitter GaugeWeightRouter · R1 Keep deploys CoilMakerStrategy · C DEXCoilfees in HUBTAREsurplus GOVveForgegauges VAULTKeepcapital MM onCoildeeper books ↻ FLYWHEEL more volume → more fees

Coil DEX → fees

trades on the intent DEX accrue protocol fees

→ TARE surplus

CoilFeeRouter (A): USDC→TARE, donated to surplus

→ veForge gauges

SurplusSplitter: senior→sTARE, junior→gauge emissions

→ Keep capital

GaugeWeightRouter (R1): votes steer vault allocation

→ markets on Coil

CoilMakerStrategy (C): deeper books → loop closes

“No vote, keeper, admin, or caller may move a solvent user’s collateral, mint on a bad price, or alter live debt. Routers only move value already released or earned.”

Every arrow moves only already-earned value. Each connection is a small, permissionless router with exactly one bounded action — it cannot mint, cannot reach a live position, cannot redirect a senior claim. The worst a bad actor can do is leave money on the table.

Phase 3 · on-chain 1.0 → 1.4 50 TARE in → sTARE share price stepped 1.0→1.4 in one tx, traced on-chain
Phase 4 · fork-proven 1000 → 1001.94 Keep made markets on real Coil: 1000 USDC in → 1001.94 out, fork-proven

Sepolia testnet · fuzzed · self-reviewed · not audited. Gauge weights activate at the weekly epoch boundary (Thu 00:00 UTC).

One engineer, working in the open

I'm Khomenkov Yuriy (KhomDev) — a solo Vyper and DeFi engineer focused on the Curve ecosystem and on protocol security. I don't ship isolated demos; I build composed systems where a stablecoin, ve-governance, a vault, and a DEX reinforce each other through small permissionless routers that move value but never hold a key to it.

My discipline is the same on every repo: write the invariant first, fuzz it hard with Hypothesis stateful machines, prove the risky integrations on a mainnet/Sepolia fork against the real contracts, then review my own work in the open and publish the trace. Everything in the ecosystem above is live on Sepolia, fuzzed and self-reviewed — and labelled honestly as not audited.

I'm a Chainlink-verified developer with a public Cyfrin profile, and I take remote contract work paid in USDC / ETH — code review, Solidity→Vyper migration, DeFi integrations, and the router-engineering pattern behind this flywheel.

Invariant-first

One carried rule since Phase 0 — no actor moves a solvent user's funds. Every contract is built to keep it.

Fuzzed, fork-proven

Hypothesis stateful suites + Sepolia-fork runs against real Coil & real Curve pools.

Open & honest

Self-reviewed in public, on-chain traces published. Testnet labelled as testnet. Not audited, said plainly.

Verified

Chainlink Developer verification · public Cyfrin profile · active on Cantina & HackenProof.

Vyper · DeFi · Ethereum

Five production-grade Vyper contracts. Four compose into the TARE ecosystem above; one stands alone. Each card notes its role in the flywheel and the routers that wire it in — all on Sepolia, fuzzed & self-reviewed, not audited.

Group 1 — The TARE Ecosystem

Four contracts, one flywheel

TARE (hub), veForge (governance), Keep (vault) and Coil (DEX) compose into the loop above. Each is live on Sepolia; the routers that wire them are listed per card. Fuzzed & self-reviewed, not audited — gauge weights activate at the weekly epoch boundary.

01 Live on Sepolia

⚖️ TARE Stablecoin

Flywheel role: HUB — Coil fees donate to surplus; Phase 3 splits surplus → sTARE savers + veForge gauge emissions via SurplusSplitter.

Overcollateralized, ETH-backed stablecoin pegged to USD. Every TARE is minted against 2× locked ETH; positions carry an on-chain health factor and permissionless liquidators restore solvency when collateral falls below the threshold. No governance token, no admin keys on the engine, no rebasing. Phase 3 added a surplus → savings (sTARE) + capped gauge-emissions split — proven on-chain: 50 TARE in → sTARE share price 1.0→1.4 in one tx.

Vyper 0.4.x Chainlink Oracle Moccasin ERC-20 Liquidations Health Factor sTARE Savings
Phase 3 routers · Sepolia
sTARE (savings)0xCc7A…107d
SurplusSplitter0x21e9…05ec
EmissionRouter (TARE)0xE652…c23A
Checks-Effects-Interactions
Oracle Staleness Guard
Health Factor Enforcement
Permissionless Liquidation
sTARE Senior · ≤30% Emission Cap
No Admin Keys on Engine
Collateral Ratio200% min
Liq. Bonus10%
Price FeedChainlink ETH/USD
Token Contract0x6475...1c93
02 Live on Sepolia

🗳️ KhomDev VeForge

Flywheel role: GOVERNANCE — ve-lockers vote gauge weights that steer Keep's capital and earn a capped slice of Coil fees in real USDC. Weights activate at the weekly epoch boundary.

Vyper 0.4 reference implementation of vote-escrowed tokenomics — VotingEscrow, GaugeController, and BribeDistributor. Modernized for the Vyper 0.4 module system, Snekmate-hardened, Moccasin + Hypothesis tested. Now the governance layer steering real money — votes never touch funds, only read by permissionless routers.

Vyper 0.4.3 Snekmate Moccasin Titanoboa Hypothesis veToken Merkle Proofs
Governance layer · Sepolia
VotingEscrow (veTARE)0x2a62…9f7B
GaugeController0xA28c…c369
BribeDistributor0x6445…16B3
Reentrancy Guard
Checkpoint Binary Search
EIP-712 Permit
Pull Payment Pattern
Merkle Claim Verification
Vote Weight Caps
CompilerVyper 0.4.3
Tests120+ (planned)
ModulesEscrow / Gauge / Bribe
03 Live on Sepolia

🏦 KhomDev Keep

Flywheel role: VAULT — capital allocation steered by gauge votes (GaugeWeightRouter / Router 1) and runs a market-making strategy ON Coil (CoilMakerStrategy / C). Fork-proven: 1000 USDC in → 1001.94 out.

ERC-4626 multi-strategy yield vault for USDC with senior/junior tranching. Smart strategy router across Aave V3, Compound V3, and Morpho Blue. HWM performance fees, Senior/Junior risk tiers, EIP-2612 permit. Now capital-steered by gauge votes and making markets on Coil via an EIP-1271 on-chain maker that can never be filled below the EMA-oracle floor.

Vyper 0.4.0 ERC-4626 EIP-2612 EIP-1271 Moccasin Tranching CoilMakerStrategy
Routers wiring it in · Sepolia
GaugeWeightRouter (R1)0x718C…e227
CoilMakerStrategy (C)0x07cD…3006
ERC-4626 Compliant
Senior/Junior Tranching
HWM Performance Fees
EMA-Oracle Floor on Maker
Keeper Can't Sell Cheap
Stateful Fuzzing
CompilerVyper 0.4.0
Tests160 (full suite)
StrategiesAave / Compound / Morpho / Coil
04 Live on Sepolia

🔄 Coil DEX

Flywheel role: DEX — the fee source feeding the loop and the venue Keep makes markets on. Phase 4 A + B live; C (CoilMakerStrategy) live. First Coil deployed on Sepolia.

MEV-resistant intent DEX with batch-auction uniform clearing and partial fills. EIP-712 typed-data signing, EIP-1271 smart wallet support, EIP-2612 permit, EIP-7702 EOA support, per-intent allowance guards. 95 tests across 8 modules. Protocol fees route — only as already-earned value — to TARE surplus (A) and to gauge voters in real USDC (B).

Vyper 0.4.0 EIP-712 EIP-1271 EIP-2612 EIP-7702 Batch Auctions Hypothesis
DEX + fee routers · Sepolia
Coil (intent DEX)0x9510…a578
CoilFeeRouter (A)0xdD4A…1547
EmissionRouter · USDC (B)0xf28A…511F
Replay Protection
Allowance Guards
EIP-7702 EOA Support
EMA-Priced Fee Swaps
recover Rejects TARE/USDC
Invariant Fuzzing
CompilerVyper 0.4.0
Tests95 + fork-proven
EIPs712 / 1271 / 2612 / 7702
Group 2 — Standalone

Independent showcase

Not part of the ecosystem — a self-contained demonstration of Chainlink VRF 2.5 and provably-fair on-chain game design.

05 Live

⚔️ NodeJackPot

Provably-fair on-chain elimination raffle with Chainlink VRF 2.5. Players buy tickets at quadratic cost, VRF eliminates participants until 3 survivors split the pot (70/20/10). Pull-payment pattern, 24-hour vesting, reentrancy guards, rolling jackpots.

Vyper 0.4.3 Chainlink VRF 2.5 Moccasin Snekmate Hypothesis Pull Payments
Reentrancy Guard
Overflow Protection
VRF Verification
Pull Payment Pattern
Access Control
Stateful Fuzzing
CompilerVyper 0.4.3
Coverage100%
Tests45+
GasOptimized

Deployed Tools

Production AI-powered tools on Google Cloud Run — on-chain intelligence, DeFi analytics, and DAO automation.

Live Whale Alert

Real-time on-chain intelligence terminal monitoring $1M+ transactions with AI-driven behavioral analysis.

Web3.py Django Gemini AI
Live DeFi Tracker

Institutional-grade asset monitoring with real-time price history and automated market risk reviews.

Pandas FastAPI Gemini Flash
Live KhomDev Auditor

Multi-stage security protocol for Vyper 0.4+ and Solidity. Integrates SAST with AI semantic synthesis.

Vyper 0.4 Slither Gemini 2.5
Live DAO Talent

Contributor intelligence portal scoring on-chain identity and governance participation for DAOs.

FastAPI LangChain SQLModel
Live CryptoScrape

Sentiment engine for Twitter & Discord with predictive FOMO analysis and batch data processing.

Playwright FastAPI Docker
Live KhomDev Narrative

Editorial AI for Web3 communications. Five streamed stages — research, draft, critique, refine, finalize — with a live word-level diff showing the editor's revisions.

FastAPI Gemini 2.5 SSE Pydantic

Tools of the Trade

The actual stack behind the TARE ecosystem and every repo above — Vyper 0.4 contracts, Snekmate building blocks, Moccasin + Titanoboa + Hypothesis for testing and fork-proofs, and the Curve / Aave / Morpho protocols I integrate against.

Smart Contracts

Vyper 0.4 Solidity Snekmate ERC-20 ERC-4626 EIP-712 / 1271 EIP-2612 / 7702

DeFi Protocols

Curve StableSwap-NG crvUSD / LlamaLend Aave V3 Compound V3 Morpho Blue Uniswap V3 Chainlink Feeds / VRF

Dev Tooling

Moccasin (mox) Titanoboa Hypothesis (stateful fuzzing) pytest Foundry Sepolia / mainnet forks web3.py

Security

Invariant design Stateful fuzzing EMA-oracle hardening MEV / sandwich resistance Reentrancy / CEI Slither

AI / Backend

Gemini API LangChain Django FastAPI Celery Redis

Infrastructure

Google Cloud Run Docker nginx PostgreSQL CI/CD

Hire Me, Paid in Crypto

Vyper 0.4 is a narrow expert pool. If you ship on Ethereum and need security-hardened contracts, integrations, or AI-driven content — these are productized engagements with fixed scope, fixed price, USDC settlement.

Hourly · Retainer $90/hr base · $3,600/mo for 10h/wk
01 / Audit

Vyper Code Review

Targeted review of a Vyper contract or module (≤500 LOC). Severity-ranked findings, suggested patches, PDF report.

  • Written PDF report
  • Severity-ranked findings
  • Suggested code patches
from $300· 2–3 day turnaround
02 / Migration

Snekmate Migration

Port a Solidity ERC-20 / ERC-721 / vault contract to Vyper 0.4 using Snekmate modules — gas-optimized, fully tested.

  • Vyper 0.4 port
  • Test parity with original
  • Moccasin project scaffold
from $600· 4–7 day turnaround
03 / Integration

Aave V3 / Uniswap V3 Integration

Atomic position-management contract wiring Aave V3 lending, Uniswap V3 swaps, and Chainlink valuation. Mainnet-fork tested.

  • Custom helper contract (Vyper)
  • Chainlink oracle wiring + slippage guards
  • Mainnet-fork test suite
from $2,250· 2–3 week build
04 / Oracle

Chainlink Oracle Adapter

Custom Chainlink price-feed adapter with staleness checks, fallback logic, and decimals normalization. Comes with fork-pinned tests.

  • Adapter contract (Vyper)
  • Staleness + heartbeat guards
  • Mainnet-fork tests
from $600· 2–4 day turnaround
05 / Hardening

TWAP / MEV-Hardening Pass

Drop-in TWAP integration and sandwich-resistance audit for an existing swap path. Includes gas report and mitigation patch.

  • TWAP integration code
  • Sandwich-attack risk report
  • Gas diff + mitigation patch
from $1,100· 1 week turnaround
06 / Bot

PHOSPHOR Trading Bot

Custom fork of PHOSPHOR — mainnet Uniswap V2 trading bot with your strategy module, TWAP pricing, nonce-safe execution, Prometheus metrics.

  • Custom strategy module
  • Backtest report
  • Prometheus dashboard + kill switch
from $2,600· 2–4 week build
07 / Composition

DeFi Protocol Composition / Router Engineering

Wire governance or DEX flow into your existing protocol with small permissionless routers — value moves, but no actor (vote, keeper, admin) gets a key to funds. The pattern behind the TARE flywheel.

  • Bounded single-action router(s) (Vyper)
  • Fail-closed invariants + Hypothesis fuzzers
  • Fork-proof run + integration writeup
from $2,500· 2–3 week build · USDC settlement
Request Finance Crypto invoice · USDC / ETH · Base · Arbitrum · Mainnet
Coinbase Commerce One-click fixed-price checkout · USDC / ETH / BTC
01

Pick a package

Tap "Request invoice" — I reply within 24h with a 1-page Statement of Work (scope, deliverables, timeline).

02

50% in USDC, work begins

Sign SOW, send 50% to my treasury wallet (Base / Arbitrum / Mainnet — your call). Daily progress updates over Telegram / email.

03

Delivery + final 50%

Code, tests, and report shipped. Final 50% on acceptance. 7 days of post-delivery support included.

Jobs over $5k? Use a Safe multisig with a neutral signer or Kleros Escrow — your choice, no extra cost.

Vyper 0.4 engineer USDC · 24h reply
Request invoice