Monthly Archives: January 2026

How I Built a 123,000 LOC Enterprise Platform in 4.4 Months as a Solo Developer

A deep dive into productivity gains, lessons learned, and the numbers behind building an enterprise analytics platform


The Challenge

In August 2025, I started building an enterprise analytics and governance platform from scratch. The scope was ambitious: natural language SQL queries, semantic search, row-level security, column-level security, attribute-based access control, dashboard builders, and more.

Traditional estimates suggested this would take 5.5 years with a single developer, or require a 12-person team working for several months.

I delivered it in 4.4 months. Solo.

Here’s the breakdown.


By The Numbers

What Was Delivered

MetricValue
Lines of Code123,430
Stories Completed100
Epics14 (13 completed, 1 planned)
Microservices6
Development PeriodAugust 7 – December 21, 2025

The Math: Traditional vs Actual

Traditional Solo Developer Estimate:

Story Points: 1,584 SP (all 14 epics)
Velocity: 12 SP per 2-week sprint (industry average)
Sprints Required: 1,584 ÷ 12 = 132 sprints
Timeline: 132 sprints × 2 weeks = 264 weeks = 66 months = 5.5 years

What Actually Happened:

Actual Effort: 211 SP (complexity-adjusted)
Velocity: 28 SP per 2-week sprint
Sprints Required: 211 ÷ 28 = 7.5 sprints
Timeline: 7.5 sprints × 2 weeks = 15 weeks ≈ 4 months

The Multipliers

  • Base Velocity: 2.3x faster (28 SP vs 12 SP per sprint)
  • Complexity Reduction: 7.5x (1,584 SP → 211 SP actual effort)
  • Overall Timeline: 15x faster than traditional estimates
  • Team Equivalence: Delivered what would traditionally require a 12-person team

What Did I Build?

The platform consists of 6 microservices plus a React frontend:

Frontend:Web UI (75,991 LOC) – React 19 with Dashboard Builder V1 & V2, 30+ widget types. Compiled into static files and served by the Service Layer.

Backend Microservices:

1. Service Layer (17,088 LOC) – Spring Boot 3.2 with OAuth2 authentication
2. Core API (11,600 LOC) – FastAPI with cloud data warehouse gateway and caching
3. NL-to-SQL Engine (7,250 LOC) – Natural language to SQL engine with LLM integration
4. Data Firewall (6,561 LOC) – SQL-level security with RLS, CLS, and ABAC
5. Semantic Search (3,263 LOC) – Semantic search with FAISS vector database
6. AI Integration Layer (1,677 LOC) – MCP protocol server for AI tool integration


Comparison with Traditional Development

AspectTraditionalActualImprovement
Planning2-3 weeks per epic2-3 days per epic7-10x faster
Implementation50-60 weeks16-18 weeks3x faster
Testing8-10 weeks2-3 weeks3-4x faster
Documentation4-6 weeks1 week4-6x faster
Overall Timeline66 months (5.5 years)4.4 months15x faster
Team Size12 developers1 developer92% reduction

Success Factors

1. Architectural Excellence

I spent significant time upfront on architecture. The microservices approach wasn’t just about scalability—it was about cognitive load management.

Key architectural decisions:

  • 6 independent, scalable microservices – Each service could be developed, tested, and deployed independently
  • API-First Design – Clear contracts with OpenAPI documentation enabled parallel development of frontend and backend
  • Clean Separation of Concerns:
    • Data Firewall for ALL security (RLS/CLS/ABAC)
    • Core API for ALL data warehouse interactions
    • Service Layer for ALL authentication
  • Technology Fit – Python for SQL parsing, Java for auth, React for UI – each technology chosen for what it does best

No overlap. No confusion. When debugging, I always knew exactly which module to look at.

2. Development Best Practices

  • Incremental Delivery: 100 stories over 132 days = 0.76 stories per day. No big bang releases—every day something shipped.
  • Git Discipline: 945+ commits over 132 days = 7+ commits per day. Small, focused commits with clear messages.
  • Security First: OAuth2, RBAC, RLS, CLS, ABAC built into the foundation from day one—not bolted on later.
  • Documentation: Complete JIRA stories and technical documentation maintained throughout development.

3. Technology Choices

I chose technologies based on what they were best at, not what was trendy:

TechnologyPurposeWhy This Choice
sqlglotSQL parsingBest SQL parsing library available; Python-only, which drove Data Firewall’s language choice
React Grid LayoutDashboard V2Proven, battle-tested library for drag-and-drop grid layouts
AG GridData tablesEnterprise-grade data grid with sorting, filtering, pagination out of the box
FAISSVector searchFacebook’s library for efficient similarity search; enables local RAG without external APIs
FastMCPAI tool integrationMCP protocol server for connecting AI tools like Cursor and Claude Desktop
Spring SecurityAuthenticationBattle-tested for enterprise OAuth2/JWT flows

4. AI-Assisted Development

A significant productivity multiplier came from AI coding assistants. I used multiple tools depending on the task:

ToolUse CaseContribution
Claude CodeComplex refactoring, architecture decisions, multi-file changesDeep understanding of codebase context; handled intricate cross-service changes
CursorDay-to-day coding, quick implementationsFast inline completions; excellent for iterating on UI components
GitHub CopilotBoilerplate code, repetitive patternsAccelerated writing of tests, DTOs, and standard CRUD operations
WindsurfCode exploration, understanding unfamiliar codeHelpful for navigating large codebases and understanding dependencies

The key wasn’t replacing thinking with AI—it was offloading the mechanical work. Architecture decisions, security design, and debugging complex issues still required human judgment. But writing boilerplate, generating test cases, and implementing well-defined patterns? AI tools handled those efficiently.

This combination reduced the “typing overhead” and let me focus on the hard problems: SQL injection prevention in the Data Firewall, cascading variable resolution, and JWT token propagation across services.


What Worked Exceptionally Well

  1. Clear Architecture from Start – Well-defined module boundaries enabled focused development and easier debugging. I never had to wonder “where does this code belong?”

  2. Microservices Done Right – Independent modules allowed me to work on one service without breaking others. Each service had its own repository, its own tests, its own deployment.

  3. Incremental Approach – Building features incrementally with regular testing reduced risk dramatically. When something broke, I knew it was in the last day’s work.

  4. Git Discipline – 945+ commits provided a clear development history. Git bisect became invaluable for tracking down issues.

  5. Technology Fit – Choosing the right tool for each job paid dividends:

    • Python + sqlglot for SQL parsing (no equivalent in Java/JavaScript)
    • Java + Spring Security for enterprise auth
    • React + TypeScript for type-safe UI development
  6. API-First Design – Defining API contracts early meant frontend and backend could be developed in parallel. No waiting for the other side to be “ready.”


Challenges Overcome

Not everything was smooth sailing. Here’s what was genuinely hard:

SQL Parsing Complexity

Building a Data Firewall that could inject WHERE clauses into arbitrary SQL while handling nested queries, CTEs, and JOINs was the hardest technical challenge. sqlglot’s learning curve was steep, but once mastered, it was incredibly powerful.

Cascading Variables

Dashboard variables that depend on other variables require topological sorting to resolve in the correct order. A user selects “Region” → that filters “Market” → that filters “Store”. Getting the dependency resolution right took multiple iterations.

Per-Instance Widget Caching

The dashboard builder allows multiple instances of the same widget with different configurations. Architecting efficient per-instance caching with UUID tracking while maintaining cache coherence was tricky.

JWT Token Flow

Propagating user context from the frontend → Spring Boot → Data Firewall → Core API—while maintaining security at each hop—required careful architecture. Each service needed to validate and forward the JWT correctly.

Full-Stack Coordination

Keeping 6 microservices plus a React frontend in sync across Spring Boot and multiple Python services was a constant balancing act. A breaking change in one service could cascade.

Multi-Environment Management

Managing dev/staging/prod configurations across all modules, with different OAuth providers, database credentials, and data warehouse projects, required disciplined configuration management.

Security Compliance

Meeting security scanning requirements meant addressing vulnerabilities as they were found, not deferring them. This added overhead but resulted in a more secure codebase.


Future Improvements

No project is ever truly “done.” Here’s what I’d tackle next:

  1. Automated E2E Testing – Expand test coverage with Selenium or Playwright. I relied too heavily on manual testing.

  2. Performance Monitoring – Implement Prometheus/Grafana observability. Currently, debugging performance issues requires digging through logs.

  3. Distributed Caching – Each service has its own cache. A shared Redis layer would improve consistency and reduce duplicate data.

  4. Dashboard V2 Enhancements – Additional widget types, more templates, and improved drag-and-drop UX.

  5. Advanced Analytics – Epic 11 (the one planned epic) covers scheduled reports, data exports, and executive dashboards.


The Takeaway

The numbers are real. 123,430 lines of code. 100 stories. 4.4 months. Solo.

But the numbers don’t tell the whole story. What made this possible wasn’t superhuman coding speed—it was:

  1. Clear architecture that reduced cognitive load
  2. Right technology choices for each problem
  3. Disciplined incremental delivery
  4. Security built in from day one
  5. Relentless focus on what mattered

The productivity multipliers compound. A 2.3x velocity improvement combined with 7.5x complexity reduction doesn’t give you 9.8x—it gives you 15x+ because the benefits reinforce each other.

Could I do it again? On a different project, with different constraints? Maybe. The principles would transfer. The specific numbers might not.

But one thing I know for sure: the traditional estimates of 5.5 years or 12-person teams aren’t wrong—they’re based on how software ‘was’ typically built.