devbundler
Launch

11 Questions to Ask Before Using a pump.fun Bundler

Eleven questions to ask any pump.fun bundler before you fund a wallet: custody, launch method, failure handling, selling, fees, practice and getting out.

By DevBundler Team · · 4 min read

The short answer

Before using any pump.fun bundler, ask who holds the keys and how you export them, whether the launch is one Jito bundle, what happens when a launch fails, how batch sells are quoted, what every action costs, and whether you can practice on devnet. A tool that cannot answer clearly is not worth the risk.

Key takeaways

  • Ask about custody first: where keys live, how they are encrypted and how you export them.
  • Ask exactly how the launch is sent. 'One Jito bundle with the create, dev buy and N buyers' is a good answer.
  • Ask how batch sells are quoted. In-order quoting is the difference between a clean exit and a pile of 6003 errors.
  • Ask which actions carry a fee and whether you see it before confirming.
  • Treat any offer to fake volume or promise profit as a reason to walk away.

Before you fund a single wallet in any bundler, you should be able to answer eleven questions about it. Most take a minute to check. If a tool cannot answer one of them clearly, that tells you something too.

We have answered each one for DevBundler as we go, so you have a reference answer to compare others against.

Keys and custody

1. Who holds the private keys?

Either the keys stay on your device and you approve signatures, or the tool's server stores them and signs for you. Both are legitimate. You just need to know which you are choosing.

DevBundler: hosted and custodial. It generates wallets (or you import keys) and stores the keys on its server so it can sign launches and trades for you.

2. How are the keys protected?

Look for a specific answer: the encryption used, what the encryption key is derived from, whether keys can appear in logs.

DevBundler: AES-256-GCM, with a key derived from your password using argon2id plus a server secret. Keys are never shown in logs, and sessions auto-lock after idle time.

3. How do I get a key out?

You should be able to export any wallet's key, and the tool should make you prove it is you first.

DevBundler: export needs your password again and shows the key for 10 seconds.

The launch itself

4. How exactly is the launch sent?

A good answer names the mechanism: "one Jito bundle containing the create, the dev buy and up to N buyers". A vague answer often means separate transactions that can land in different blocks, with room for outside buyers in between.

DevBundler: on mainnet, one Jito bundle of five transactions holding the create, the dev buy and up to 10 buyers, using a reusable lookup table. On devnet, sent one after another since there is no Jito.

5. How are buys sized and quoted?

Each buy on the bonding curve pays a little more than the last. The tool should quote every wallet after the ones before it, and ideally let you buy by percentage of supply.

DevBundler: buy by SOL or by %, the same for all or custom per wallet, quoted in send order. A table shows each wallet's estimated share and SOL needed.

6. What does it check before sending, and what happens on failure?

DevBundler: wallets short on SOL block the launch; buys that would sell out the curve are blocked. Right before sending, one fast check confirms pump.fun is reachable, the coin address is unused and balances are fine. If it fails, nothing is sent, and the project page shows the reason with "Launch again". What to do when a launch fails covers the common causes.

After launch

7. How do batch sells work?

This is the question people forget. If ten sells are all quoted against the same starting price, later ones fail slippage with error 6003.

DevBundler: tick wallets or All, press a sell preset or type a percentage. Every wallet is quoted in order so later minimums stay reachable. On mainnet you can send as Fast (each wallet at once) or, on Premium, as one Jito bundle.

8. What happens when the curve completes?

The coin migrates to PumpSwap. Does the tool keep working?

DevBundler: trading switches to PumpSwap automatically.

9. How do I get SOL back out?

DevBundler: consolidate sweeps wallets back into one, optionally keeping rent or closing token accounts (each holds about 0.002 SOL of rent, refunded on close).

Cost

10. Which actions cost money, and when do I see it?

Launch only, or every trade? A percentage, a flat fee, a subscription? Shown before you confirm, or discovered afterwards?

DevBundler: a percentage fee on the SOL spent in launch buys and on dashboard buys and sells, shown before you confirm, with lower rates possible on larger trades. Premium is an optional monthly plan paid in SOL. Network costs (Jito tip, priority fees, rent, pump.fun's own fees) come on top with any tool. Pump.fun bundler fees explained shows how to compare models.

~0.003 SOL

extra per launch wallet on top of its buy

~0.03 SOL

extra for the dev wallet, plus fee and tip

~0.005 SOL

one-time lookup table setup per account

Practice

11. Can I practice for free?

DevBundler: yes, on devnet with free test SOL. Devnet has no Jito and its pump.fun curve is configured differently, so percentages will not match mainnet, but the whole flow is the same.

The questions on one page

Bring this to any bundler

  • Who holds the keys?
  • How are they encrypted?
  • How do I export one?
  • Is the launch one Jito bundle, and what is in it?
  • Are buys quoted in send order? Can I buy by %?
  • What is checked before sending, and what happens on failure?
  • How are batch sells quoted?
  • Does it keep working after migration to PumpSwap?
  • Can I sweep all wallets back and close token accounts?
  • Which actions carry a fee, and do I see it before confirming?
  • Can I practice on devnet?

If you want to turn these answers into a score, how to choose a pump.fun bundler has a scoring checklist.

Frequently asked questions

›What should I check before using a pump.fun bundler?

Check who holds the wallet keys, how the launch is sent, what happens if it fails, how batch sells work, what it costs and whether you can test on devnet. Then run a full launch and sell on devnet before any real SOL.

›How do I know if a bundler is legit?

A legitimate tool explains its custody model and fees plainly, never asks for your main wallet's seed phrase and does not promise profit. Get its address from an official source rather than a DM or reply.

›What happens if a bundled launch fails?

On mainnet, a Jito bundle is all or nothing, so a failed bundle means none of the transactions landed. A good tool checks before sending and tells you why it failed. DevBundler shows the reason on the project page with a Launch again button.

›Can I get my SOL out of a bundler easily?

You should be able to. Ask whether the tool can sweep all wallets back into one and close token accounts to recover rent, and whether you can export each wallet's key.

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