Founding Architect @ 7Zen LabsAvailable for Advisory & Fractional Roles

Engineering mission-critical systems with uncompromising correctness & speed

Partnering with ambitious founders and engineering leaders to architect resilient, maintainable distributed platforms, offline-first systems, and production engineering foundations that scale.

Zero DriftInteger Currency MathZero float calculation errors
Offline FirstSQLite WAL Outbox100% network disconnection resilience
<20ms EdgeGlobal Distributed RoutingCloudflare V8 Anycast runtime
WORM LedgersCryptographic Audit TrailsTamper-evident SHA-256 state
01About & Architecture
Download CV / Dossier
Systems Architecture & Technical Governance

Focused on high-correctness engineering, local-first data resilience, and production-grade architectures that solve hard real-world problems.

Founding Systems Architect and Co-Founder at 7Zen Labs. I partner with venture-backed startups and deep-tech founders to design resilient distributed platforms, local-first architectures, and production-grade engineering foundations that pass institutional VC due diligence.

Deterministic ArchitectureByte-Level CorrectnessVenture Roadmap Execution
View Verified CV
Metrics
0.00Paisa Ledger Drift (Integer Math)
<20msEdge Routing Latency
100%Offline Resilience
WORMCryptographic Audit Trail
India • Available Worldwide

Enterprise Technology Stack & Tooling

React 19Next.js (App Router)TypeScriptTailwind CSS v4Motion / FramerWeb Standards & PWAAstro
Core Architectural Invariants & Governance
PILLAR 01Hardware-Level Correctness
Deterministic State & Zero-Drift Financial Accounting

Abolishing floating-point representations across financial domains. Guaranteeing 100% mathematical correctness through 64-bit integer paisa arithmetic and atomic local transactional boundaries.

0.00 Paisa Calculation Drift across 1M+ ledger records
Ref: RetailOS Architecture
PILLAR 02Zero Network Blocking
Autonomous Offline-First Edge Resilience

Treating client devices as sovereign local-first nodes. All writes commit locally within <4ms via append-only outbox journals, syncing idempotently when connectivity restores.

100% Operational Continuity during total network blackouts
Ref: Distributed Edge Platform
PILLAR 03Tamper-Evident WORM
Immutable Cryptographic Auditability & Governance

Append-only Write-Once-Read-Many (WORM) audit ledgers with SHA-256 state chaining. Database-level triggers permanently block mutation or deletion, providing tamper-evident regulatory proof.

Cryptographic non-repudiation via append-only SHA-256 block-chained ledgers
Ref: RxCompliance & Healthcare Engines
02Journey & Track Record

Engineering Milestones

Proven record of architecting scalable web applications, enterprise systems, and client solutions.

Co-Founder & Chief Technology Officer

7Zen Labs•Remote
2026 — Present

Directing systems architecture, edge infrastructure, and technical strategy. Architecting sovereign operations infrastructure and high-precision offline PWAs (Aaj) on Cloudflare edge infrastructure.

Cloudflare WorkersAstroTypeScriptCloudflare D1PythonArchitecture

Founding Systems Architect & Technical Partner

Independent Systems & Edge Advisory (Founding Practice)•India / Remote
2024 — 2025

Advised venture-backed startups and engineering teams on distributed workflow engines, zero-cold-start edge compute on Cloudflare Workers, and tamper-resistant audit infrastructure.

TypeScriptCloudflare WorkersD1 SQLEdge ArchitectureSecurity

Principal Solutions Architect (Healthcare & Compliance)

Clinical Regulatory Systems (HealthTech Venture)•India
2023 — 2024

Architected hospital pharmacy compliance engines, AST dynamic rule orchestrators, and Drug-Drug Interaction decision matrices. Designed stage-gated pipelines (M01-M08) with formal Module Acceptance Records.

Python FastAPISQLAlchemyPostgreSQLAlembicRedisCelery

Founding Systems Engineer

RetailOS (Offline-First Enterprise POS)•India
2021 — 2023

Engineered native Android point-of-sale platforms, integer-paisa financial ledgers, and offline-first transactional sync outbox architectures.

Native AndroidKotlinJetpack ComposeRoom SQLiteOffline Outbox
03Systems Architecture

Featured Systems & Production Architectures

Mission-critical platforms, local-first offline architectures, and formal compliance engines built for high correctness.

RxCompliance system logoRxCompliance
AST Rule Engine & DDI Matrix
RxCompliance — Enterprise AST Audit Engine interface preview
Inspect High-Res UI

Enterprise regulatory compliance and audit tracking engine designed for clinical pharmacies, distributor inventory validation, and cold-chain compliance verification.

Python FastAPISQLAlchemyPostgreSQLAST Rule EngineAlembic
RetailOS system logoRetailOS
Zero-Float Integer Paisa
RetailOS — Offline-First Native Android POS interface preview
Inspect High-Res UI

High-throughput native Android point-of-sale and inventory platform engineered with integer-paisa financial safety, local Room SQLite persistence, and offline-first transactional sync outbox.

Native AndroidKotlinJetpack ComposeRoom SQLiteOffline Outbox
CarePulse system logoCarePulse
127KB Admin HUD & D1 SQL
CarePulse — Clinical Operations & Triage Platform interface preview
Inspect High-Res UI

Mission-critical clinical operations ecosystem streamlining patient triage queues, appointment verification, multi-department telemetry, and administrative records.

Next.js 15React 19Cloudflare D1Tailwind CSSTypeScript
Aaj system logoAaj
R&D Study • Golden-Set Verified
Aaj — Offline Indian Daily Almanac (PWA R&D Beta) interface preview
Inspect High-Res UI

Consumer daily almanac PWA (in active R&D) featuring build-time Swiss Ephemeris astronomical precomputations and an automated CI gate isolating AGPL code from client distribution bundles.

AstroPWAPython SwissEphLicense IsolationOffline-First

Interested in architecture reviews or mission-critical system design? Initiate an executive discussion

04Advisory & Systems Engineering

Architectural Advisory & Engineering

High-conviction technical advisory, scalability audits, and bespoke 0-to-1 platform builds for ventures requiring mission-critical correctness.

Strategic Leadership

Founding & Fractional CTO Advisory

High-leverage engineering leadership, stack governance & investor tech due-diligence for ambitious startups.

Ideal For: Funded Startups & Venture Studios
Starts From:Starts from $2,500/mo • Tailored to roadmap & cadence
Scope & Deliverables
End-to-end tech stack evaluation & scalable architectural roadmaps
Technical due-diligence representation for seed & Series A investors
Core engineering team vetting, code quality gates & sprint governance
Preventing early technical debt, vendor lock-in & costly rewrites
Technical StrategyArchitecture GovernanceInvestor DDTeam Scaling
Hire as Fractional CTO
1–2 Week Deep Dive

Architecture & Scalability Audit

Comprehensive codebase, concurrency, and database isolation review before critical launches or scaling.

Ideal For: Scaling Tech Platforms & Pre-Launch Products
Starts From:Starts from $1,800 • Scoped to codebase size & depth
Scope & Deliverables
Deep-dive codebase review, concurrency analysis & threat modeling
Database isolation & race-condition bottleneck resolution (Postgres/SQLite)
Zero-trust audit readiness & regulatory compliance assessment
Actionable RFC remediation blueprint with concrete performance benchmarks
Codebase AuditDatabase ConcurrencyThreat ModelingRFC Blueprint
Request Architecture Audit
Zero to One Execution

Custom Mission-Critical System Build

Full-cycle engineering of production-grade offline POS, clinical compliance, and distributed platforms.

Ideal For: Retail, Fintech & Healthcare Enterprises
Starts From:Starts from $4,500 • Milestone-based, scoped to requirements
Scope & Deliverables
Fault-tolerant offline-first architectures (Room SQLite WAL + sync outboxes)
Strict financial invariants (64-bit integer paisa math with zero rounding drift)
Tamper-evident append-only WORM audit ledgers & AST decision engines
Full IP ownership transfer with comprehensive architectural documentation
Offline-First POSClinical ComplianceMulti-Agent AIFull IP Transfer
Commission a System Build

💡 Flexible Engagements: Final rates are customized based on technical scope, architecture complexity, and delivery milestones.

Run Free 60s Diagnostic ⚡
Engineering Governance

Architectural Principles & Working Standards

Initiate Executive Discussion
Direct Principal Collaboration

Zero junior delegation or agency middlemen. Direct architecture partnership with the Co-Founder & CTO.

Mathematical Correctness

Byte-level schema certitude, 64-bit integer money math, and zero float rounding drift across transactions.

Sovereign IP Ownership

100% intellectual property assignment and commercial rights transferred under bilateral NDA protections.

High-Bandwidth Cadence

Transparent asynchronous velocity with verifiable milestone deliveries and 12–24h response SLAs.

Interactive Zero-Touch Architecture Probe

Production Edge & Security Header Audit

Engineered for Startup Founders, CTOs & Engineering Leads. Probe live edge TTFB latency, TLS handshakes, unmasked origin headers, HTTP/3 compression, and missing security invariants (HSTS, CSP, X-Frame-Options).

Quick benchmarks:
Zero Code Access RequiredReal-Time Edge ProbeZero Marketing Fluff • 100% Architecture
05Technical Blog & Architecture

Technical Blog & Deep Dives

Deep dives into local-first offline resilience, multi-agent AI coordination, and enterprise healthcare architectures.

Architecting Offline-First Point-of-Sale: Integer Paisa Math and Transactional Sync Outboxes technical editorial banner
Local-First Systems9 min read

Architecting Offline-First Point-of-Sale: Integer Paisa Math and Transactional Sync Outboxes

In high-throughput retail environments with fluctuating connectivity, client-side point-of-sale software cannot afford network blocking or floating-point rounding errors. This architectural deep dive examines how 64-bit integer paisa math, Room SQLite WAL transactions, and an idempotent sync outbox state machine guarantee zero data loss and sub-second checkout speeds.

Native AndroidKotlinRoom SQLite
Read Article
Getting Autonomous AI Swarms to Review GitHub PRs Without Hallucinating technical editorial banner
Multi-Agent AI9 min read

Getting Autonomous AI Swarms to Review GitHub PRs Without Hallucinating

Autonomous multi-agent swarms sound magical until Agent A refactors a function, Agent B reverts it because of missing types, and they burn through $50 in API tokens arguing with each other. Here is how we engineered GH-Swarm using strict state machines, verification gates, and AST diff validation.

Multi-Agent AIGitHub ActionsArchitecture
Read Article
What 2 AM Hospital Bugs Taught Me About Database Isolation technical editorial banner
Systems Architecture8 min read

What 2 AM Hospital Bugs Taught Me About Database Isolation

When building the Pharma Compliance Engine for hospital pharmacies, an audit failure is not a mild inconvenience: it carries legal liability and patient safety risks. Here is how we designed append-only ledger tables, bi-temporal tracking, and row-level security in PostgreSQL that survive regulatory inspection.

PostgreSQLDatabaseHealthcare
Read Article
06Systems FAQ & Invariants

Architectural FAQ & Credentials

Verifiable specifications regarding 7Zen Labs, offline-first integer math invariants, clinical AST decision engines, and technical advisory models.

Seeking custom architecture review, database isolation audits, or fractional CTO governance?
Initiate Direct Inquiry
Get in Touch

Let's Build Something Great Together

Have a project in mind, an exciting role, or looking for technical guidance? Drop a note below and let's talk.

Status & Availability
Open for Projects

I work with ambitious founders, engineering leads, and fast-moving teams to build reliable 0-to-1 platforms, resolve system bottlenecks, and architect clean software that scales.

Whether you need an MVP built from scratch, a deep codebase review, or full-stack technical leadership, feel free to reach out.

contact@harvindersingh.in
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