SpecState

SpecState

System design for critical software

I help teams design backend systems, workflows, and protocols before the wrong assumptions get baked into code. When useful, I use formal verification and TLA+ to make behavior precise.

Book a design review

What I do

I work on the parts of a system that are easy to get wrong on paper

Most system design problems are not about syntax. They are about behavior: what can happen, what must not happen, and what the system should do when reality gets messy.

  • Backend systems with tricky state and failure handling
  • Workflows with retries, ordering, permissions, and approvals
  • Protocols and state machines that need exact behavior
  • AI agent flows with tools, handoffs, and side effects

Who this is for

For teams building systems where behavior matters

  • Engineering leads working through hard system design problems
  • Founders with technical teams building core backend logic
  • Teams shipping workflows, protocols, or stateful product behavior
  • Teams that want clearer system behavior before writing a lot of code

Services

How I work

Design Review

1

I review one system, workflow, or protocol and point out the assumptions and failure cases that need to be fixed before implementation.

System Modeling

2

I model the behavior of a system when the rules are hard to reason about informally, using formal verification and TLA+ when useful.

Advisory or Implementation

3

I stay involved after the design work when you need help turning the design into code without losing the original intent.

Why formal verification

I use it when plain reasoning is not enough

  • Most teams do not need formal verification everywhere.
  • It helps when a system has enough state, ordering, retries, or coordination that informal reasoning stops being reliable.
  • I use formal verification and TLA+ when that is the clearest way to make the behavior precise.

Contact

Bring me in before the design turns into code

Reach out if you are working through backend system design, workflows, protocols, state machines, or formal verification work.

contact@specstate.com