Should I wait until they pay to send the code?

That is a contract choice. Either way, timestamp what you send when you send it.

Repo invite instead of a zip?

Timestamp a zip of the commit you invited them to, so you have bytes under your control.

What if they ask for the private key or credentials?

Do not put secrets in the timestamped zip. Deliver credentials by a separate agreed channel.

Your first Pooled TimeBind is free, with no credit card required. After that, from US$5; ASAP is US$15. See plans and pricing

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Freelance code delivery: timestamp before the client pays

Inna Hall

November 10, 2026

November 12, 2026

Guides

Flat illustration of a proof certificate, a data server and a desk clock

Before you hand over a build or repo zip, timestamp the exact delivery. TimeBinder^® makes a fingerprint in your browser. The files stay on your device. You get a checkable Proof of Time Certificate that shows that exact delivery existed no later than a recorded time. It does not show who wrote the code, who owns it, or that the client must pay. Free to start. See timestamping for freelancers and source code timestamping.

The routine: timestamp before you deliver
Payment holds and scope fights
What a TimeBind shows, and what it doesn’t
Frequently Asked Questions

The routine: timestamp before you deliver

Export the delivery (zip of the agreed branch, build artefacts if included, and a short README of what is included).
Optional. Check the hash with the free SHA-256 hash checker.
Timestamp the zip (add the invoice PDF if you want both in one TimeBind). Your first Pooled TimeBind is free, with no credit card required.
Save the Proof of Time Certificate with your copy.
Then deliver the link or zip to the client.
Fixes after feedback are new deliveries. Timestamp each paid milestone.

How to timestamp a file has the steps. Prove source code existed before a date explains limits of git dates.

Payment holds and scope fights

Disputes often turn on “what did you send, and when?” Email attachments get re-saved. A dated zip matches later only if you kept those bytes. Keep the statement of work and messages about scope. A timestamp does not create an invoice obligation; it dates the files.

What a TimeBind shows, and what it doesn’t

A TimeBind shows that this exact file existed no later than the recorded time. It does not show authorship, ownership or copyright, and it does not force payment. Keep contracts and invoices. This is general information, not legal advice. For design freelancers in a similar spot, see client used your design without paying.

If an assistant helped write the delivery set, the free vibe-coding review checklist asks whether you can explain and review the change before you hand it over. It does not scan the files.

Your file’s fingerprint, anchored to a global network secured by real electricity and cryptography.

Editing a file—including with AI—changes its fingerprint, not its existing network record.

How this works

Your file’s SHA-256 fingerprint, a short code worked out from its exact contents, is made in your browser, and the file itself stays on your device. A cryptographic commitment to that fingerprint, which may be combined with others, is then anchored in a block on the Bitcoin blockchain. Bitcoin is secured by proof of work: computers around the world spend real electricity to add each block, and changing an earlier block would mean redoing that work faster than the rest of the network. Until that block is confirmed, your proof is pending. Once the Bitcoin anchoring is confirmed, you can verify the proof against that recorded commitment. The confirmed record can then be checked; Pooled TimeBinds are checked through TimeBinder, while ASAP TimeBinds can also be checked independently. If you check the file later and its fingerprint still matches, that shows the file existed no later than the recorded time. The record doesn’t show who made the file, whether AI was used, or that its contents are true.

Your filestays on your device
FingerprintSHA-256
Network timestampon Bitcoin

Frequently Asked Questions

Should I wait until they pay to send the code?

That is a contract choice. Either way, timestamp what you send when you send it.
Repo invite instead of a zip?

Timestamp a zip of the commit you invited them to, so you have bytes under your control.
Source and invoice in one TimeBind?

Yes, up to 10 files.
What if they ask for the private key or credentials?

Do not put secrets in the timestamped zip. Deliver credentials by a separate agreed channel.
What does it cost?

Your first Pooled TimeBind is free, with no credit card required. After that, from US$5; ASAP is US$15. See plans and pricing

Timestamp your next delivery free

Show that this exact file existed no later than a recorded time. Files stay on your device. Get a checkable Proof of Time Certificate. Free to start. Open TimeBinder

Inna Hall

Inna Hall is an Australian lawyer admitted to the Supreme Court of Queensland and the High Court of Australia in 2013. She has worked across government and private legal practice and is the director of TimeBinder, focusing on document authenticity, evidentiary risk, and blockchain-based proof of existence.