Digital compute infrastructure & security advisory · Worldwide

Specialized compute, and the security discipline that proof-of-work infrastructure deserves.

Planet B 21 operates SHA-256 compute capacity and AI inference credit infrastructure, and advises on digital asset custody architecture, signing schemes, and mining-network security. Built on deep operational experience, delivered through modern payment rails and clear engagements.

Practice Areas Active
Compute SHA-256 · AI Inference
Custody Multi-sig · Signing
Security Mining networks · AI infrastructure
Engagement Retail · B2B · Enterprise
Coverage Worldwide

Proof-of-work infrastructure is serious work — it should be treated that way.

The space is moving from early-adopter experimentation into critical infrastructure that families, businesses, and operators depend on. The gap between that reality and the operational maturity of most services in the space is where we focus. We build and advise with the same discipline you would expect from any regulated financial-infrastructure company.

— 01

Depth over breadth

We work in three narrow, related domains — SHA-256 compute, digital asset custody architecture, and mining-network security — where operational depth matters more than surface area.

— 02

Rails first

We work with regulated payment providers and established banking counterparties. Every upstream relationship completes business verification under a single legal entity. Nothing is routed through shells.

— 03

Security as baseline

Whether it's our own hashrate operation or a client engagement, the same security posture applies: non-custodial where possible, least-privilege always, documented and reviewable in practice.

Three practice areas, one operating company.

Each service is delivered by Planet B 21 directly. Engagements are scoped, priced, and documented in writing. Hashrate is available through self-serve channels; consulting practices engage by inquiry.

01
SHA-256 Compute
Live
Hashrate as a service

Fiat-native access to SHA-256 compute capacity.

Purchase contracted SHA-256 compute capacity in standard units (TH/s, PH/s, EH/s) with mining rewards routed directly to a pool account you control. We are not in the custody path — you provide the pool identifier, the upstream provider delivers the hashrate, the rewards flow to you.

For retail customers, our consumer brand Cash to Hash (cashtoha.sh) offers SHA-256 hashrate and AI inference credits with fiat-native checkout and minimal verification. For larger orders, capacity is arranged directly with Planet B 21.

AI Inference Credits. For AI inference, we offer prepaid compute credits delivered as privacy-preserving Cashu tokens, accessible via fiat payment and redeemable through the Routstr provider network. No Bitcoin wallets required.

What's included
  • Card, ACH, Bitcoin, and Lightning payment
  • Non-custodial reward routing (hashrate)
  • Non-custodial token delivery (AI credits)
  • Capacity dashboard with delivery logs
  • Single legal counterparty of record
  • Minimal verification account onboarding
  • Clear, written terms & refund policy
Buy retail capacity at Cash to Hash →
02
Custody & Signing
By inquiry
Consulting engagements

Secure storage and enterprise-ready signing, designed for the way your organization actually works.

Holding digital assets at scale is a discipline. The choices that look small early — key generation environment, quorum structure, recovery path, signing device policy, ceremony documentation — determine whether your position is actually safe a decade from now. We advise individuals, companies, and treasuries on designing, implementing, and operating those systems.

Every engagement starts with a threat model specific to your situation. We are vendor-neutral on hardware and software; our job is to match the architecture to the actual adversaries you face, not to sell you a product.

Representative work
  • Multi-signature architecture & policy design
  • Hardware signer evaluation & selection
  • Key ceremony design and facilitation
  • Recovery and inheritance planning
  • Signing device policy for organizations
  • Audit & review of existing setups
Start a conversation →
03
Mining Network Security
By inquiry
Advisory for mining operators

Defending mining operations from the adversaries that actually target them.

A mining datacenter is not a generic enterprise network. Its threat model includes pool account takeover, firmware-level compromise of fleet ASICs, hashrate redirection, stratum interception, operational-technology disruption, and insiders with physical access to the floor. Generic security advice — even good generic advice — does not cover it.

We advise operators, datacenter owners, and hosting providers on the specific security posture their environments require, drawing on direct experience running and securing mining infrastructure at scale.

Engagement scope
  • Network segmentation & stratum isolation
  • Fleet firmware & configuration integrity
  • Pool account & payout security
  • OT / SCADA exposure review
  • Insider-threat and physical-access controls
  • Incident response playbooks for mining ops
Visit HashSentinel →

One legal entity, three brands.

Planet B 21, LLC is the parent company and sole legal counterparty of record behind every product and engagement below.

Start a specific conversation.

Tell us what you're working on. We'll respond with a scope and whether we're the right fit — or point you somewhere better if we're not.