Mev Protection

MEV protection for PumpKit

This skill is the project-specific defense playbook. Companion: tutorials/50-mev-defense-patterns.md.

Mental model

Solana has no global mempool, so classical Ethereum-style frontrunning doesn't apply. The real threats are:

You can't eliminate any of these — only raise their cost above their profit.

The defense matrix

Slippage policy

const SLIPPAGE_BPS = {
  contested:    100,   // 1%  — launches, hot coins, MEV environments
  default:      500,   // 5%  — most quiet trades
  illiquid:    2000,   // 20% — tiny coins, pre-graduation thin curves
} as const;

function maxQuoteIn(targetCost: bigint, regime: keyof typeof SLIPPAGE_BPS): bigint {
  const bps = BigInt(SLIPPAGE_BPS[regime]);
  return (targetCost * (10_000n + bps)) / 10_000n;
}

Rules:

• Never use unbounded slippage. If a caller doesn't specify, reject the call. (Number.MAX_SAFE_INTEGER is not a slippage policy.)
• Always pair tight slippage with a retry path. Otherwise users disable slippage when it reverts too often.
• Chunk into N sub-buys for large entries. Each chunk has its own slippage check.

Wallet rotation

The shape of a defensible rotation:

1. Pre-grind a pool of deployer keypairs. Vanity grinding is slow; don't do it during a launch. Keep ~10 ready in tmp/ (gitignored).
2. Seed each from independent funding sources. Direct transfer from your main wallet defeats the rotation — chain analysis links them.
3. Verify funding upstream: run npx tsx tools/check-pump-funding.ts <pubkey> before launch. A deployer flagged as pump-seeded is itself a signal.
4. Single-use per launch. Never reuse a deployer for a second launch.
5. Keep keypair files mode 600 and never git add them. bash tools/check-file-permissions.sh enforces this; run it in CI.

RPC privacy

Privacy is a head-start, not invisibility. Once the tx lands, it's permanent and public.

Adversarial simulation

Before any high-value send:

const sim = await conn.simulateTransaction(tx, { sigVerify: false, commitment: 'confirmed' });
if (sim.value.err) throw new Error(`Sim failed: ${JSON.stringify(sim.value.err)}`);

const logs = sim.value.logs ?? [];
const expectedEvents = ['Buy event', 'TradeEvent'];
const missing = expectedEvents.filter(e => !logs.some(l => l.includes(e)));
if (missing.length) {
  throw new Error(`Expected events not in sim logs: ${missing.join(', ')}`);
}

What this catches: stale state, wrong quote mint (USDC vs WSOL on V2), curve already complete. What it doesn't: sandwiches that haven't happened yet.

Use .claude/commands/simulate-tx.md for the canonical pattern.

Migration-window protocol

Alarms at curve progress thresholds:

See .claude/agents/migration-detector.md for monitor wiring.

Operational hygiene checklist

Run through this before any production deployment:

• Keypair files are mode 600. (bash tools/check-file-permissions.sh)
• .gitignore covers *.env, *keypair*.json, tmp/leaked-launch/.
• Bot tokens are read from env, never committed.
• Logs redact bot tokens, full signatures (if PII-adjacent), and RPC URLs containing secrets.
• CI secrets are masked in build output.
• No remote signer service. Sign locally.
• If you ship a Docker image, secrets are in env / mounted files, not in the layer.

A defended launch, end to end

Plan
────
- Coin: USDC-paired, V2
- Entry: 3 wallets, 1.0 USDC each, atomic
- Tip budget: 0.02 SOL (contested-launch urgency)
- Wallets: pre-grinded, seeded from independent sources, never used before

Pre-flight
──────────
[ ] tools/check-file-permissions.sh         passes
[ ] tools/check-pump-funding.ts <deployer>  not seeded by pump
[ ] tools/check-pump-funding.ts <walletA-C> not seeded by pump
[ ] All four keypairs verified as the intended pubkeys
[ ] Mint vanity matches the program's required suffix

Bundle
──────
tx[0] create_v2(deployer, mintKp, USDC_MINT)
tx[1] buy_v2(walletA, mintKp.publicKey, 1.0 USDC, slippage 1%)
tx[2] buy_v2(walletB, mintKp.publicKey, 1.0 USDC, slippage 1%)
tx[3] buy_v2(walletC, mintKp.publicKey, 1.0 USDC, slippage 1%)
tx[4] (auto-appended) tip 0.02 SOL

Send
────
- Endpoint: Jito mainnet block engine (NOT a public RPC)
- Confirm via getSignatureStatuses + /bundle-trace cross-check

Post
────
- For the first 30s: monitor curve state, watch for sandwich patterns
- After 30s: sniper window has mostly closed; resume normal trading rules

See also

• tutorials/50-mev-defense-patterns.md
• tutorials/48-jito-bundle-strategies.md
• tutorials/37-security-auditing-verification.md
• .claude/agents/mev-defender.md
• .claude/skills/jito-bundles/SKILL.md