PRINCIPAL SOFTWARE ARCHITECTURE · built for the AI era

We make software production-grade - including software built with AI.

For founders, CTOs, and engineering leaders shipping B2B SaaS, payments, or AI-assisted products.

AI made shipping code cheap. It didn't make shipping products safe. We're the architects teams bring in a few days a week so that velocity doesn't turn into breaches, outages, and cloud bills.

The problem

// why fractional, why now

Your team ships faster than ever. Your security, architecture, and operational discipline don't.

The failures land later - as incidents, licensing problems, and invoices. Our job is to make sure they don't land at all.

Ways to work with us

// remote · worldwide · Israel-based
ongoing · 1-3 days/week

Fractional principal architect

Your senior-most technical voice, part-time.

  • Architecture & technical decision ownership
  • Security posture and tenant-isolation review
  • Payment flows and money-path design
  • Cloud cost and infrastructure strategy
  • Written decision log - institutional memory as a deliverable

Monthly retainer, sized by days/week

Fits: teams of 2-20 engineers shipping fast without a principal-level architect on staff.

Relevant evidence: security flaws stopped before launch · cloud spend cut 84% →
fixed scope · 1-2 weeks

Production-readiness review

A structured audit of what you're about to ship.

  • Authorization boundaries & tenant isolation
  • Money paths: idempotency, refunds, webhooks
  • Deploy reversibility & rollback planning
  • Secret handling & supply-chain exposure
  • Findings ranked by blast radius - with fixes, not just a report

Fixed price, quoted on repo count & scope

Fits: pre-launch, pre-fundraise, or post-incident.

Relevant evidence: a payment release stopped before every refund could fail →
fixed scope · 1 week

AI-assisted engineering audit

How your team actually uses AI coding tools - and what that's exposing.

  • Secret handling in agent sessions & logs
  • Supply-chain policy: pinning, scripts, provenance
  • Agent guardrails & permission boundaries
  • Review discipline that verifies instead of trusts
  • A written, machine-followable policy your team keeps

Fixed price, one week, one deliverable

Fits: any team where AI writes a meaningful share of the code.

Relevant evidence: AI-agent policy created after a real credential leak →
  1. 01
    Start with the failure mode

    A 30-minute risk review gives us the product, the release, and the decision that matters most.

  2. 02
    Scope a decision, not a vague retainer

    Choose the smallest engagement that resolves the highest-risk unknown.

  3. 03
    Leave with usable proof

    Prioritized findings, a decision log, and a clear next move stay with your team.

The blueprints

// three systems, drawn the way we build them

Scroll through three architectures we design and defend in production: an event-driven distributed system, a retrieval-augmented AI pipeline, and the software delivery lifecycle rebuilt for the AI era.

* simplified for illustration - these are the basic shapes, not fixed solutions. Real architectures are designed to each product's constraints and scale.

system 01 · messaging & data flow

Event-driven distributed system

CLIENTS web · mobile API GATEWAY authn · authz · rate-limit ORDERS SVC PAYMENTS SVC ORDERS DB LEDGER DB one service · one schema OUTBOX EVENT BUS at-least-once NOTIFY WORKER BILLING WORKER DLQ dead-letter after N retries idempotent consumers retry + backoff OBSERVABILITY metrics · traces · alerts · versioned deploys · one-step rollback

swipe the schematic sideways to explore

  1. Edge & boundaries

    Every request enters through one authenticated gateway, and each service owns its data and its schema - nothing reaches a database it doesn't own.

  2. Decouple with events

    Writes publish through an outbox to an event bus, so a slow consumer never blocks an order - and a crash never loses one. Delivery is at-least-once by contract.

  3. Design for duplicates & failure

    At-least-once means duplicates will happen: consumers are idempotent, retries back off, and poison messages land in a dead-letter queue instead of vanishing.

  4. Observe & reverse

    Metrics, traces, and alerts prove the system is healthy - and versioned deploys keep one documented step back from every release.

system 02 · retrieval-augmented generation

RAG, production grade

OFFLINE · INDEXING PIPELINE SOURCES docs · tickets · code PARSE + CHUNK EMBED embedding model VECTOR INDEX metadata · tenant tags ONLINE · QUERY PIPELINE QUERY TENANT FILTER deterministic HYBRID RETRIEVAL BM25 + vector · fused RERANK top-50 → top-5 enforced before retrieval - never by the model INJECTION GUARD content ≠ commands CONTEXT data, not instructions LLM grounded prompt ANSWER + citations GROUNDEDNESS EVALS faithfulness · context precision · hallucination rate learnings feed back into chunking & prompts

swipe the schematic sideways to explore

  1. Index offline

    Documents are parsed, chunked, and embedded into a vector index carrying metadata and tenant tags - a batch pipeline, kept separate from the query path.

  2. Retrieve hybrid, then rerank

    Queries run keyword and vector search in parallel, fuse the results, and rerank a wide candidate set down to the few chunks worth the context window.

  3. Isolate & guard

    Tenant scope is enforced deterministically before retrieval - never by the model. Retrieved content is treated as data, not instructions, to blunt prompt injection.

  4. Ground & evaluate

    Answers cite the context they stand on, and groundedness evals score every release - hallucination becomes a measured rate, not an anecdote.

system 03 · delivery lifecycle

The AI SDLC

SPEC + INVARIANTS humans own intent AI AGENTS code tests docs parallel · bounded by policy DETERMINISTIC GATES lint · types security scan secret-leak scan runs at generation speed HUMAN REVIEW judgment only where needed every finding verified TRUST NOTHING · VERIFY EVERYTHING DEPLOY canary · rollback ready TELEMETRY SLOs · error budgets production learnings feed the next spec

swipe the schematic sideways to explore

  1. Spec first

    Humans own intent: constraints and invariants are written before an agent writes code, so 'done' is defined by the spec - not by the demo.

  2. Agents implement

    AI agents build code, tests, and docs in parallel - bounded by policy, with scoped credentials and pinned dependencies.

  3. Verify, don't trust

    Deterministic gates - lint, types, security, leak scans - run at generation speed; human judgment reviews what remains, and every AI finding is verified before it is believed.

  4. Ship & learn

    Releases go out with a rollback path and telemetry that proves they work - and what production teaches feeds the next spec.

Evidence, not adjectives

// selected engineering outcomes, 2014 - today
Security · multi-tenant SaaS

Found a cross-tenant data-access flaw in review - before launch, not after a breach

Caught in a pre-implementation review, not an incident. Stopped feature work, audited the entire platform for the same class of flaw, closed the process gap that allowed it - then fixed the code.

closed pre-launch · full-platform audit shipped
Cloud · cost
-84%

Cut AWS spend without collapsing the architecture

~$10K/year saved at pilot scale. Wrote the non-negotiable invariants first: no monolith collapse, every service boundary preserved, and a documented one-weekend path back to Kubernetes.

production cutover 2026-06 · running since
Payments · reliability
100%

Blocked our own release over a defect that would have failed every refund

A live end-to-end test showed the provider contract differed from what the docs implied. Declared NO-GO on our own evidence, fixed it, and proved exactly-once refund semantics under replay before shipping.

replay-tested on live provider · shipped
AI-era engineering · security

Wrote the AI-agent security rulebook - after a real incident, not in theory

An AI coding agent leaked credentials into a session log. We wrote a machine-followable secret-handling and supply-chain policy, propagated it into every agent session, and wired an automated leak check into the deploy pipeline.

enforced in CI · held since
AI-era engineering · quality
46

Real defects fixed in one pass - every AI finding hand-verified first

Six review agents fanned out across a seven-repo feature. 48 raw candidates, each confirmed by direct code read; one killed as a false positive. 46 fixes across 11 reviewed PRs, deployed together.

48 → 46 confirmed · 1 false positive killed
Payments · compliance

Restructured payments so the company never holds other people's money

Designed out a money-transmitter licensing exposure across IL/EU/US before writing code - restaurant as merchant of record, platform fee separate. Read the provider's full API documentation page by page; one buried error code invalidated the refund-retry design.

licensing exposure designed out
Legacy modernization · team leadership
+60%

Modernized a national telecom's legacy mobile systems

Led a six-developer team migrating legacy Java applications to Kotlin with modern architecture patterns - improving application efficiency by up to 60% across products used on Android, iOS, and smart-TV platforms.

delivered as team lead · national telecom
Automation · growth engineering

Built automation that multiplied client business exposure

Designed Python automation and business-growth systems for consulting clients - increasing profile exposure and interactions by up to 800%, built on the same reliability discipline as everything else here.

delivered via consulting practice

Track record

// three ways we've shipped software for a decade
venture · founder & architect

Brasserio

A restaurant reservation & operations SaaS: ten Python microservices on AWS, event-driven workflows, payments, GitOps delivery, and staff apps from a single Kotlin Multiplatform codebase - designed, built, and operated by one architect.

2app stores, live
3platforms, 1 codebase
7languages, incl. RTL
leadership · mobile team lead

Consumer mobile & TV apps

Led a six-developer team delivering consumer mobile and smart-TV applications for a national telecom - owning delivery lifecycle, technical reviews, mentoring, and architecture modernization across Kotlin, Swift, and Java stacks.

6developers led
+60%efficiency gain
5yras lead
consulting · since 2014

DevYouUp practice

Backend, mobile, web, cloud, and automation systems delivered across industries - selecting the stack for the product, not the trend, and recruiting and mentoring remote teams when delivery demanded it.

national telecomfintechhealth techEdTechAdTechcybersecurityB2B / SaaSrestaurant tech

Experience

// the full timeline lives on LinkedIn

Twelve years of planning, architecting, and shipping software: cloud-native distributed systems, backend platforms, web and mobile apps - from national-telecom scale to single-architect SaaS, across eight industries.

The practice covers the full lifecycle - owning architecture and high-risk technical decisions, writing production code, interviewing, hiring, and mentoring engineers, building teams, modernizing legacy systems, and carrying products from first diagram to live app stores. Certified in software architecture; working in English and Hebrew, with RTL products shipped.

architecturedistributed systemsbackendfrontendmobilecloudpaymentsAI SDLCteam building & hiring
Full timeline on LinkedIn ↗

Questions teams ask before release

// specific answers for specific risks
Does AI-generated code still need a production-readiness review?

Yes. AI can accelerate implementation, but it does not prove authorization boundaries, payment behaviour, rollback safety, or secret handling in production.

How do you check a payments release before it goes live?

Test against the live provider contract, exercise retries and refunds, and prove the intended idempotency and rollback behaviour before release.

What does a fractional principal architect do?

Owns architecture and high-risk technical decisions a few days a week, with a written decision log that stays with the team.

What should I bring to a 30-minute risk review?

The product, the release you are considering, the team size, and the decision or failure mode that concerns you most.

Our AI feature demos well. Why is production a different story?

A demo proves the happy path once. Production has to survive adversarial input, cost spikes, model updates, and tenant boundaries. We review evaluation coverage, guardrails, fallback behaviour, and data isolation before an AI feature ships.

AI writes a growing share of our code. How do we keep review meaningful?

Treat every AI-written change and every AI review finding as a claim to verify, not a fact to trust. We help teams put deterministic gates before human review, so people spend judgment only where it is actually needed.

How do we stop AI coding agents from leaking secrets or pulling in risky dependencies?

With a written, machine-followable policy: scoped credentials, pinned dependencies, install scripts disabled, and automated leak checks in the pipeline. We wrote ours after a real incident - and it has held since.

Our cloud and AI costs grow faster than usage. What are the architectural levers?

Cost is an architecture property, not a billing surprise: right-sized models and infrastructure, caching, batching, and clear cost ownership per feature - with the invariants written down before anything is cut.

Can we add AI features to a multi-tenant product without leaking data between tenants?

Yes - if isolation is enforced deterministically at every layer the AI touches: retrieval scope, prompts, caches, logs, and telemetry. A language model must never be the thing that enforces access control.

When is a rewrite justified - and when is the boring architecture right?

Rewrite when the current design blocks a measurable business outcome; otherwise evolve it. We write the non-negotiable invariants first, keep a documented way back, and treat 'no change' as a valid recommendation.

NEXT STEP

Tell us what you're shipping. We'll tell you what will break.

A 30-minute call is enough to know whether we can help. If we can't, we'll say so - the same way we declare NO-GO on our own releases.

Two quick details help us point you to the right starting point.

We reply within one business day.

Book a 30-minute risk review → oraneventzur@devyouup.com LinkedIn ↗

Prefer async? Email works. We respond within one business day, Israel time (GMT+3).