Review, Remediation, and Upgrades

Review

Core Technical & Security Evaluation

GreyBound Review is a technical and security assessment of a Bitcoin system that already exists: wallet, signing path, node, backend, indexer, or side chain. Do this before mainnet funds or a public launch. The client gets an executive summary, a risk register, a remediation roadmap, and a validation plan. This is not a public contest report.

Review is for architecture and trust boundaries. Remediation is for issues already named. Upgrade is for new features in a product that already runs.

The client receives:

• Executive Summary (overall system state, key risks, immediate priorities, readiness for the stated goal)
• Findings / Risk Register (problem, affected component, technical impact, security/reliability impact, severity, evidence, conditions required for exploitation/failure, recommended remediation)
• Prioritized Remediation Roadmap
• Architecture / Engineering Recommendations
• Validation Plan (tests, security validation, configuration checks, regression checks, re-review where necessary)

Remediation

Technical & Security Issue Remediation

GreyBound Remediation fixes Bitcoin infrastructure issues the client already knows or that Review found. The work is code, configuration, architecture, and operations on the running system, then checks and handoff.

The client receives:

• Scoped Fix Plan (agreed issue list, priority order, acceptance criteria, and change risk)
• Implemented Fixes (code, configuration, architecture, and operational changes as required)
• Verification Evidence (tests, security checks, configuration checks, and regression results)
• Change Documentation (what changed, why, how to operate it, and residual risk if any)
• Handoff for Follow-up (clear next steps, including targeted re-check or re-review where necessary)

Upgrades

Feature Development & Product Enhancement

GreyBound adds features to a Bitcoin wallet or signing stack that already ships. The work goes into the live codebase: descriptors, PSBT flows, multisig, hardware-signer paths, fee and coin selection, and the backend or indexer the wallet uses.

This is for

• a mobile, desktop, or extension Bitcoin wallet that already exists
• a signing service or non-custodial payments path that already exists
• Bitcoin or a side chain the client already runs

This is not for

• building a new wallet from nothing
• a template wallet for many chains

The client receives:

• Feature Scope & Design (requirements, interfaces, constraints, and Bitcoin/security considerations)
• Implementation on the Existing Product (features delivered into the live codebase)
• Tests & Validation (unit/integration coverage, security-relevant checks, and regression protection)
• Documentation & Handoff (how the feature works, how to operate it, and how to extend it)
• Upgrade Path Notes (rollout considerations, compatibility, and production readiness for the change)

What we need from you

To start, we need the running system:

• what is live today
• what must not break
• what you want changed or proved
• who can answer questions on the repo

If the system signs or moves bitcoin, we need enough of the signing path to trace one transaction from screen to bytes. If you cannot share that yet, say so. We will say what we can still do.

What the work is

A Review maps trust boundaries and names what can lose funds.

Remediation changes the running code or config and shows the check.

An Upgrade adds a feature in that same codebase.

What we decline

We do not produce a public audit PDF meant only for a launch page.

We do not take a chain we do not operate.

We do not build a new wallet from nothing for every network.

Email contact@greybound.tech. We reply in 1–2 business days.