https://lethra.io/blog/ Retention, cryptographic evidence, provable deletion, and the architecture decisions behind Lethra. en Thu, 13 Aug 2026 09:00:00 GMT https://lethra.io/blog/a-company-in-cyprus-and-data-in-germany/ https://lethra.io/blog/a-company-in-cyprus-and-data-in-germany/ Where a company is registered and where its data physically sits are separate questions with separate answers. Both of ours are deliberate, and the reasoning is the kind a compliance reviewer will ask for anyway. Thu, 13 Aug 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) company sovereignty infrastructure https://lethra.io/blog/what-we-chose-not-to-build/ https://lethra.io/blog/what-we-chose-not-to-build/ No Kubernetes, no service mesh, no event bus, no dashboard for end users, no document management features. Each omission was a decision with a reason, and the reasons are more useful than the list. Thu, 06 Aug 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) architecture engineering scope https://lethra.io/blog/four-regimes-one-api-surface/ https://lethra.io/blog/four-regimes-one-api-surface/ Retention rules differ by jurisdiction and change over time. Putting that behind a declared regime keeps it out of partner code, and makes the schedule an auditable artefact rather than a scattered assumption. Tue, 28 Jul 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) product api-design architecture https://lethra.io/blog/the-deposit-as-a-unit/ https://lethra.io/blog/the-deposit-as-a-unit/ One sealed envelope, one key, one lifecycle. Why the whole system is built around a single unit of retention, and what breaks in designs that pick a coarser one. Thu, 16 Jul 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) architecture product data-model https://lethra.io/blog/proof-that-outlives-the-provider/ https://lethra.io/blog/proof-that-outlives-the-provider/ Most compliance tooling produces evidence that stops working when the vendor does. Three verification paths, each less dependent on us than the last, and the third works with no connection to us at all. Thu, 09 Jul 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) verification cryptography trust https://lethra.io/blog/the-provider-that-can-read-your-archive/ https://lethra.io/blog/the-provider-that-can-read-your-archive/ If an archive provider can read what they hold for you, the risk was duplicated rather than outsourced. No certification changes that, because the exposure is a capability rather than a policy. Thu, 02 Jul 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) threat-model encryption risk https://lethra.io/blog/signing-once-a-day-instead-of-700000-times/ https://lethra.io/blog/signing-once-a-day-instead-of-700000-times/ The obvious version of our signing design needed around 700,000 hardware signatures a month. Batching them into a daily Merkle root brought it to roughly 100, with the customer-side guarantee unchanged. Thu, 25 Jun 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) cryptography merkle-trees architecture cost https://lethra.io/blog/what-deletion-means-in-a-distributed-system/ https://lethra.io/blog/what-deletion-means-in-a-distributed-system/ A delete call returns a status code, not evidence. Between that call and the bytes being unrecoverable sits a chain nobody outside the provider can inspect. Crypto-shredding closes the gap. Thu, 18 Jun 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) cryptography deletion key-management https://lethra.io/blog/storage-is-the-cheap-part/ https://lethra.io/blog/storage-is-the-cheap-part/ Long-term document retention is usually costed as a storage question. The storage line turns out to be a rounding error, and the four properties that actually matter are not things a bucket provides. Thu, 11 Jun 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) architecture evidence storage https://lethra.io/blog/the-bureaucracy-did-not-disappear/ https://lethra.io/blog/the-bureaucracy-did-not-disappear/ A generation of platforms removed paperwork from the user's day. The obligations attached to that paperwork did not vanish — they landed on the platform, which was built for speed rather than for keeping things. Fri, 05 Jun 2026 09:00:00 GMT office@lethra.io (Lethra Technologies Ltd.) retention platforms evidence