John Karanja

Fixed-price reviews

Know what to fix first

Two short, fixed-scope reviews for founders and small teams. You get evidence, a clear plan and a readout call, before you commit to more development.

Architecture review

USD 1,200fixed · about 10 days

Find out where your system is sound, where it is fragile and what to change first. One application, one critical user journey and its integrations.

You get

  • An annotated diagram of the system as it is
  • Findings ranked by impact, with evidence and explicit unknowns
  • A recommended design and its trade-offs
  • A prioritised implementation brief
  • A readout call and one round of clarifications

Not included

Code changes, deployment, load or penetration testing, security certification.

Payments and ledger integrity check

USD 1,500fixed · about 14 days

Find where a payment could be lost, repeated or recorded wrongly. One payment or payout flow and its ledger trail, traced with a redacted sample. No live transactions.

You get

  • A payment-state map
  • Traceable findings, and the evidence that is missing
  • A failure-case test matrix
  • Prioritised fixes with acceptance checks
  • A readout call and one round of clarifications

Not included

Financial audit, tax or accounting opinion, smart-contract audit, handling credentials, moving funds or implementation.

How it works

  1. Email a short description of the system and the question you need answered.
  2. We agree the scope, the inputs and read-only access. Nothing starts before that.
  3. I review, then walk you through the findings on a call.
  4. Any implementation is quoted separately, as phases you can stop after.

Email to book a review

Back to the home pageinfo@johnkaranja.comPrices exclude any taxes that apply to you.