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Legal & Experimental Advisory

Terms of Service

Effective Date: October 31, 2026

Project Status: Solo Indie Developer Project • Proprietary Public Beta / Experimental

Experimental Software & Cryptographic Advisory

Solo Indie Project Notice: Sphurja is an independent, proprietary software project created and maintained by a solo indie developer—not a corporation, business entity, or open-source foundation.

Experimental Cryptography Warning: While our pairwise 1-to-1 ratcheting relies on standard, battle-tested Signal Protocol primitives, our custom edge architecture—including the RFC 9807 OPAQUE Virtual HSM (Cloudflare Durable Objects) and the Blind Mailbox Storage Spool (Cloudflare D1/Queues)—are novel, experimental implementations that have not yet undergone formal, third-party independent cryptographic audits.

DO NOT USE THIS SERVICE for life-critical, high-threat-model, state-level adversary, medical, financial, or hazardous communications. The software is provided purely for testing, personal exploration, and experimental evaluation.

By accessing or using the Sphurja mobile applications, companion web clients, and edge messaging services (collectively, the "Service"), you agree to be bound by these Terms. If you do not accept these Terms, do not use the Service.

1. Non-Custodial Architecture & Key Ownership

Sphurja is strictly non-custodial:

  • You generate and retain your private identity keys and session states locally on your device.
  • The developer cannot decrypt, view, modify, or intercept your private conversations, images, or calls.
  • You maintain sole responsibility for safeguarding your device, your authentication credentials, and your recovery keys.

2. Virtual HSM, PIN Recovery & The 10-Attempt Auto-Shred Invariant

Sphurja offers an experimental zero-knowledge recovery mechanism powered by an RFC 9807 OPAQUE Password-Authenticated Key Exchange (aPAKE) Virtual Hardware Security Module (Virtual HSM) running inside per-user Cloudflare Durable Objects:

  • Experimental Protocol: Unlike the industry-standard Signal Protocol library, the Virtual HSM is an experimental indie implementation of RFC 9807 OPAQUE and Oblivious Pseudorandom Functions (OPRF). It may contain bugs, timing variances, or edge-case failure modes.
  • 10-Attempt Hardware-Grade Auto-Shred Invariant: To protect against offline brute-force attacks on user PINs, the Virtual HSM enforces a strict threshold. If ten (10) consecutive incorrect PIN attempts are registered, the Virtual HSM permanently and irreversibly destroys and shreds your OPAQUE PIN vault (shredOpaqueVault).
  • 64-Digit Master Recovery Key: If your vault is shredded, your sole remaining recovery path is your offline 64-digit Master Recovery Key. The developer has no backdoor, master key, or administrative override to reconstruct shredded vaults or restore lost PINs.
  • Assumption of Risk: If you forget your PIN or trigger vault auto-shredding without possessing your 64-digit key, your encrypted history is lost forever. You expressly assume all risks related to credential loss.

3. Blind Mailbox Catch-up Spool & 30-Day Retention

Sphurja implements a blind spool adapted from Meta's Labyrinth / Iris architecture:

  • Edge servers store only sealed ciphertext envelopes (senderMailboxEnvelope and recipientMailboxEnvelope) that the server cannot read.
  • The edge mailbox is an ephemeral store-and-forward catch-up buffer, not a permanent cloud backup service. Rows in the edge database are automatically pruned after thirty (30) days. Your permanent chat history exists only on your local devices.

4. Multi-Device Companion Linking

You may link up to a maximum of five (5) companion devices (e.g. Sphurja Web). Linking delegates cryptographic trust via an Ed25519 device certificate signed by your primary phone. You are solely responsible for securing physical access to any browser or companion device you authorize, and you should immediately revoke lost or shared devices from Settings.

5. Two-Tier Purge & Unsend Limitations

When you unsend a message or delete a chat, Sphurja initiates an immediate synchronous purge (less than 5ms hot path) in Cloudflare D1 and posts an ingest tombstone barrier to drop delayed queue deliveries. However, Sphurja cannot physically delete messages from recipient devices that have already decrypted the content, are operating offline, or are using modified clients.

6. Intellectual Property & Proprietary Rights (Not Open Source)

Sphurja is a proprietary software application developed and owned exclusively by the independent solo developer. Sphurja is NOT open-source software.

  • Exclusive Ownership: All client source code, compiled binaries, edge Cloudflare Worker scripts, Durable Object implementations, database designs, branding, logos, graphics, and interface designs are the private, proprietary intellectual property of the developer.
  • License Grant: You are granted a limited, personal, revocable, non-exclusive, non-transferable license to install and run the compiled client applications solely for personal communications.
  • Prohibitions: You may not reverse-engineer, decompile, disassemble, copy, modify, redistribute, create derivative works from, scrape, sublicense, or commercially exploit any part of the Service or its underlying code without explicit prior written authorization from the developer.

7. Acceptable Use Policy

You agree to use Sphurja solely for lawful communication. You must not use the Service to:

  • Transmit illegal material, including child sexual abuse material (CSAM), non-consensual imagery, or violent extremist content.
  • Conduct automated spam, phishing, harassment, or denial-of-service attacks.
  • Exploit, probe, or reverse-engineer the Virtual HSM, Cloudflare Durable Objects, or edge APIs without prior authorization.

8. Subpoenas & Technical Impossibility

Because Sphurja is non-custodial and operates on blind envelopes, the developer has no technical capability to decrypt your messages, eavesdrop on calls, or supply cryptographic keys to third parties, law enforcement, or government agencies under any subpoena or court order. The only data technically present on servers consists of basic connection metadata (account registration date, phone number, and transient network logs).

9. Absolute Disclaimer of Warranties ("AS IS")

THE SERVICE IS PROVIDED BY A SOLO INDIE DEVELOPER ON AN "AS IS" AND "AS AVAILABLE" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. TO THE MAXIMUM EXTENT PERMITTED UNDER APPLICABLE LAW, THE DEVELOPER EXPRESSLY DISCLAIMS ALL WARRANTIES, INCLUDING MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE, NON-INFRINGEMENT, AND CONTINUOUS AVAILABILITY.

NO ADVICE OR INFORMATION, WHETHER ORAL OR WRITTEN, OBTAINED FROM THE DEVELOPER SHALL CREATE ANY WARRANTY. THERE IS NO GUARANTEE OF UPTIME, ZERO DATA LOSS, OR CRYPTOGRAPHIC FLAWLESSNESS.

10. Strict Limitation of Developer Liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, IN NO EVENT SHALL THE SOLO DEVELOPER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES (INCLUDING LOSS OF DATA, LOSS OF CRYPTOGRAPHIC KEYS, VAULT AUTO-SHREDDING, SYSTEM OUTAGES, SERVICE TERMINATION, REPUTATIONAL INJURY, OR FINANCIAL LOSS), REGARDLESS OF THE THEORY OF LIABILITY (CONTRACT, TORT, STRICT LIABILITY, OR OTHERWISE), EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

IF ANY PORTION OF THIS LIMITATION IS FOUND INVALID, TOTAL AGGREGATE LIABILITY FOR ALL CLAIMS ARISING OUT OF OR RELATING TO THE SERVICE SHALL BE STRICTLY CAPPED AT ZERO DOLLARS (USD $0.00).

11. Governing Law & Contact

These Terms shall be governed by the laws of India, without regard to conflict of law rules. If you have questions or wish to report a security vulnerability or bug, contact the developer at:

Project Developer: [email protected]
In-App Support: Open Sphurja > Settings > Help > Contact Support