METACODE OY // ARCHITECTURE & BACKEND ADVISORY

Rock-Solid Software Architecture & Backend Engineering.

Built to last. 25 years in production across fintech, high-scale SaaS, and regulated platforms. Finnish craftsmanship, zero architectural fluff.

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HELSINKI, FINLAND

ID: 3375232-1

Production Track Record

25+ Years

Fintech, SaaS & Regulated Systems

Backend Type Rigor

Level 10

PHPStan Max Strictness Guarantee

Test Suite Standard

95%+

Automated PHPUnit & Integration Tests

Patented Innovation

2 Granted

European Software Measurement Patents

Cloud Architecture

Multi-Cloud & Sovereign EU

AWS, GCP & High-Security European Infrastructure

CORE PILLARS

What We Do

Hands-on architectural leadership for mission-critical software. We eliminate architectural fluff, vendor traps, and fragile codebases before they turn into costly re-platforming nightmares.

01 / FOUNDATION

Software & Solution Architecture

Designing scalable distributed systems from scratch, modernizing monolithic legacy systems, domain boundaries, and zero technical debt.

Key Deliverables & Focus

Distributed systems design & high-availability topology

Legacy monolith deconstruction into resilient microservices or modular monoliths

Domain-Driven Design (DDD) with clean bounded contexts

Defensive architecture preventing technical debt accumulation

Zero-latency distributed state & caching strategies

99.99% AvailabilityZero Tech DebtDecoupled Domains

02 / EXECUTION

High-Performance Backend & Integrations

Mission-critical APIs (REST, webhooks), relational database optimization (MySQL schema & query profiling), and autonomous AI agent tooling (Model Context Protocol / MCP).

Key Deliverables & Focus

Sub-millisecond REST & webhook integration pipelines

Relational database profiling, indexing strategies & deadlock elimination

Autonomous AI agent toolchains using Model Context Protocol (MCP)

High-throughput transactional queue systems (Redis, Kafka, AMQP)

Automated idempotency, rate limiting, and backpressure handling

Sub-ms LatencyMCP Server EndpointsMySQL Profiling

03 / GOVERNANCE

Security, Cloud Architecture & European Sovereignty

Application-layer encryption, hardened IAM/SSO models, and resilient cloud architectures across AWS, GCP, and sovereign European infrastructure.

Key Deliverables & Focus

Enterprise cloud architectures across AWS and Google Cloud Platform (GCP)

Zero-Knowledge application-layer encryption (XChaCha20-Poly1305)

Granular multi-tenant Role-Based Access Control (RBAC) & SSO/IAM

Sovereign European infrastructure deployments (UpCloud, Linux) for strict data residency and NIS2 compliance

Auditable cryptographic key derivation and secret management

AWS & GCPXChaCha20-Poly1305Sovereign EU

PROVEN DELIVERIES

Selected Work & Case Studies

Real systems operating under regulatory scrutiny, massive concurrency, and strict security constraints. Here is how we design and engineer for resilience.

CASE 01ROLE: Lead Architect & Founder

Visit Live Platform

PromptEasy.eu — Sovereign AI Governance Platform

Proprietary SaaS / Enterprise AI Prompt Management

Zero-Knowledge application-layer encryption (XChaCha20-Poly1305), Model Context Protocol (MCP) server endpoints for autonomous agents, multi-tenant RBAC, automated onboarding.

Architectural Execution & Highlights

•Client-side & application-layer cryptographic isolation guaranteeing that neither database admins nor cloud providers can inspect sensitive enterprise AI prompts.

•Native Model Context Protocol (MCP) server endpoints allowing autonomous AI coding assistants (Claude Desktop, Cursor, Antigravity) to securely fetch company prompt templates with granular token telemetry.

•Multi-tenant RBAC engine with zero cross-tenant leakage and automated team seat provisioning.

•Hardened Linux container topology running entirely on UpCloud sovereign Finnish infrastructure.

•Cryptographic GDPR Erasure vs. Audit Trail Integrity: Engineered an elegant data lifecycle engine enabling verifiable hard-deletion of users, sensitive prompts, and entire tenants (Right to be Forgotten) while mathematically preserving immutable cryptographic audit trail integrity and ledger continuity.

Verified Metrics

XChaCha20-Poly1305 Encryption

Live MCP Server

100% EU Data Residency

Verifiable GDPR Hard-Delete

Technology Stack

PHP 8.4 / Laravel 12TypeScript / Next.jsMySQL 8.4DockerModel Context Protocol (MCP)UpCloud European Cloud

CASE 02ROLE: Core System Architecture & Technical Advisory

Deterministic AI Recruitment & Talent Screening Platform

High-Throughput Candidate Evidence & Screening Pipeline

High-throughput screening pipeline pairing deterministic business logic with surgical LLM evidence extraction. Zero hallucinations, minimal token consumption, and strictly human-led qualification decisions.

Architectural Execution & Highlights

•Two-tier pipeline: Hard deterministic rules filter objective disqualifiers first, minimizing expensive model invocations.

•Surgical Context Pinpointing: Constrained decoding and structured schema enforcement eliminate generative hallucinations when extracting and surfacing candidate evidence, ensuring human evaluators retain 100% ownership of qualification scoring and decisions.

•Asynchronous background worker queues managing burst recruitment traffic with graceful backpressure.

•Comprehensive audit trail for algorithmic fairness and human-in-the-loop review overrides.

Verified Metrics

-78% Token Consumption

Zero Hallucinations

Deterministic Routing

Technology Stack

Modern Web ArchitectureLLM OrchestrationRelational Data ModelingAsynchronous QueuesTypeScript

CASE 03ROLE: Senior Backend Engineering & Compliance

Regulated Cryptocurrency Exchange & Custody

FIN-FSA Supervised Financial Infrastructure

Hardened transaction APIs, automated AML/KYC workflows, and supervisory reporting under FIN-FSA (Finnish Financial Supervisory Authority) oversight.

Architectural Execution & Highlights

•ACID-compliant double-entry ledger architecture ensuring zero discrepancy under high-concurrency order placement and trade settlement.

•Automated real-time sanctions screening, suspicious transaction flagging, and automated AML/KYC pipeline integrations.

•Immutable append-only audit logs providing cryptographic non-repudiation for regulatory audits.

•Strict defense-in-depth API network perimeter with zero direct database exposure.

Verified Metrics

FIN-FSA Supervised

Zero-Loss Ledger

Real-Time AML Scoring

Technology Stack

High-Security REST APIsPHPMySQLAudit Logging PipelinesCryptographic Signatures

CASE 04ROLE: Senior Backend & API Architecture

Global Electric Vehicle Charging Infrastructure

High-Concurrency IoT Cloud Telemetry & Mobile APIs

Core mobile API interfaces and event-driven backend services powering a distributed international IoT charging network.

Architectural Execution & Highlights

•Sub-second mobile charging session authorization across tens of thousands of distributed EV chargers.

•Event-driven telemetry ingestion pipeline handling continuous charging curves, meter reads, and power delivery adjustments.

•Fault-tolerant offline buffer reconciliation during cellular network dropouts at remote charging stations.

•Automated roaming billing integrations across European e-mobility operator networks.

Verified Metrics

Sub-Second Auth

Tens of Thousands IoT Endpoints

Cross-Border Roaming

Technology Stack

Microservices ArchitectureHigh-Concurrency API GatewaysCloud TelemetryREST / WebhooksDistributed Caching

CASE 05ROLE: Lead Technical Architect — Enterprise Key Account

Global Aftermarket & Device Lifecycle SaaS

Dedicated Architecture & Financial Reporting for Flagship Enterprise Client

Led end-to-end technical architecture and hands-on delivery for the platform’s largest global enterprise client, bridging executive stakeholder requirements with high-volume workflow automation, financial reporting, and sub-second performance.

Architectural Execution & Highlights

•Dedicated Technical Ownership: Served as the primary engineering partner and trusted architect for the platform’s flagship enterprise account, turning complex multi-market operational demands into robust, maintainable system features.

•Financial Metrics & Ledger Engines: Engineered mission-critical financial reporting, multi-currency ledger reconciliation, and automated billing pipelines tracking high-volume device lifecycle transactions.

•Database & State Machine Optimization: Restructured complex repair lifecycle state machines and resolved database contention bottlenecks, sustaining sub-second response times across high-throughput global repair hubs.

•Technical Leadership & Delivery: Balanced hands-on core architectural delivery with active developer mentoring, establishing strict code quality baselines, automated test standards, and predictable CI/CD release cycles.

Verified Metrics

#1 Enterprise Account

Multi-Currency Financials

Global Service Scale

Technology Stack

PHP (High-Performance MVC)JavaScriptMySQL (High-Concurrency Schema)REST APIsFinancial Data ModelingLinux Containers

ENGINEERING RIGOR

Engineering Standards

We hold backend systems to mathematical proof standards. Code is built to survive decades in production without breaking, silently corrupting state, or requiring frantic midnight hotfixes.

STATIC ANALYSIS: MAX

PHPStan Level 10 Static Typing

Maximum Type Rigor & Proof of Correctness

Zero tolerance for loose types, mixed returns, or unhandled edge cases. Every backend class is statically proven correct before code reaches testing or deployment.

COVERAGE >= 95%

95%+ Automated Test Coverage

Comprehensive Unit, Integration & Mutation Testing

Automated PHPUnit suites, integration tests, and scenario simulations act as executable specifications. No production release without green test pipelines.

ENCRYPTED AT REST & IN TRANSIT

Zero-Trust & Zero-Knowledge Architecture

Cryptographic Tenant Isolation & Data Privacy

Data is encrypted at the application layer with modern primitives (XChaCha20-Poly1305). Systems are designed assuming perimeter compromise — data remains unreadable without user keys.

SCHEMA-DRIVEN & STRICT

Strict API Contracts & OpenAPI

Deterministic Schemas & Zero Breaking Changes

Every integration boundary is formally governed by OpenAPI 3.1 specifications with automated runtime validation. Strictly typed request/response envelopes, robust idempotency keys, and backward-compatible versioning guarantee zero silent contract breakage across distributed services.

LEVEL 4/5 AGENT READY

Agent-Ready Architecture (RFC 9329 & MCP)

Built for Autonomous AI Systems & Crawlers

First-class Model Context Protocol (MCP) server endpoints, RFC 9329 linksets, structured markdown mirrors, and semantic HTML for autonomous LLM agents.

ZERO-DOWNTIME CI/CD

Deterministic Blue-Green Deployments

Zero-Downtime Cutover & Automated Rollbacks

Production deployments must never interrupt live customer sessions or drop in-flight transactions. We engineer hardened CI/CD delivery pipelines featuring automated blue-green container rotation, strict health-check gating, and backward-compatible zero-downtime database migrations. Any anomaly triggers immediate, automated traffic rollback.

OFFICIALLY RECOGNIZED INTELLECTUAL PROPERTY

Co-Inventor of 2 Granted European Software Patents

Patented innovations in automated web browser runtime profiling, execution latency measurement, and deterministic benchmarking methodologies under the European Patent Office (EPO).

EPO GRANTED

ENGAGEMENT MODELS

How We Partner With You

Direct B2B delivery through Metacode Oy. Clean commercial contracts, clear deliverables, and immediate access to 25 years of battle-tested software engineering leadership.

MODEL 01

B2B Contract Architecture & Engineering

TARGET: Enterprise deliveries, regulated platforms, mission-critical SaaS

Senior Lead / Architect embedded with your engineering leadership. Hands-on system design, core backend delivery, and architectural ownership under Metacode Oy contract.

Key Deliverables

Full architecture specification & ADRs (Architecture Decision Records)

Mission-critical core backend implementation (PHP/Laravel, TypeScript)

Database schema design, indexing, and high-concurrency profiling

Automated test suite (95%+ coverage) & CI/CD pipeline

Inquire for Availability→

MODEL 02

Architecture Reviews & Performance Audits

TARGET: Companies preparing for scale, M&A due diligence, or tackling tech debt

Deep-dive technical audit of existing codebases, database health, security postures, and architectural bottlenecks. Unvarnished truth with an actionable remediation roadmap.

Key Deliverables

Database query profiling & lock contention analysis

Security posture & encryption mechanism evaluation

Type safety & test coverage audit (PHPStan L10 benchmark)

Executive summary for CTO/Board + prioritized engineering punch-list

Inquire for Availability→

MODEL 03

Fractional CTO & Technical Advisory

TARGET: Fast-growing technology firms needing senior technical steering

Strategic technical steering, vendor-free tooling decisions, sovereign cloud infrastructure strategy, and technical mentoring for internal leads.

Key Deliverables

Long-term technology roadmap & sovereign infrastructure roadmap

Vendor evaluation & avoidance of proprietary vendor lock-in

AI agent integration strategy (MCP tooling & deterministic pipelines)

Technical interview screening for senior engineering hires

Inquire for Availability→

DIRECT CONTACT

Let's Build Systems That Endure.

Whether you require a senior software architect for a critical enterprise delivery, an unvarnished audit of a struggling codebase, or strategic guidance on Model Context Protocol (MCP) and sovereign cloud deployments, reach out directly.

CLOUD & INFRASTRUCTURE POSTURE

Metacode operates its own proprietary SaaS platforms and internal workloads exclusively on sovereign European cloud infrastructure (UpCloud Sovereign Cloud, FI-HEL1 and FI-HEL2, 100% EU data residency). For client engagements, we design, deploy, and harden distributed architectures natively across AWS, Google Cloud Platform, and hybrid sovereign European clouds, strictly guided by client security, regulatory, and scalability requirements.

AWS & GCP NativeGDPR & NIS2-ReadyEncrypted at Rest

Jouni Tuovinen

Founder & Lead Software Architect

Metacode Oy • Helsinki, Finland

Business ID: 3375232-1VAT: FI33752321

DIRECT EMAIL

jouni@metacode.fi

PHONE / SIGNAL

+358 50 307 8306Mon–Fri 09:00–17:00 (EET / UTC+2)

LinkedIn Profile PromptEasy.eu (SaaS)