EC

Erick Castillo

Lead .Net/Azure Developer

View Portfolio

Hexaware Technologies

Lead .NET Developer

October 2025 - February 2026

The Problem

The ELA platform's five-developer team came in with mixed experience levels and uneven exposure to the codebase, Clean Architecture conventions, and the modern .NET stack the platform was moving toward. On a federal contract with hard milestones, the team couldn't afford a slow, sink-or-swim onboarding curve — knowledge had to transfer fast, and it had to stick. Beyond onboarding, there was no shared rhythm for code review, no consistent forum for surfacing tricky architectural decisions, and no defensible record that mentorship was actually happening. Skills gaps left unaddressed would have shown up later as production defects on a 24/7 government-facing platform.

The Solution

Built and ran a structured knowledge-transfer and mentorship program for the five-developer team covering KT sessions, mob-coding exercises, and code reviews as deliberate teaching moments rather than just gates. Made skill development a tracked part of the engagement rather than a side effect, and used the program to enforce Clean Architecture, CQRS, and the team's AI-native engineering standards consistently across the team.

Implementation

Established a weekly KT cadence covering ELA platform architecture, the Clean Architecture layering the team used, CQRS / MediatR patterns, EF Core configuration conventions, and the Azure services the platform depended on. Ran mob-coding sessions where the team would tackle a real ticket together — one driver, the rest navigating — so junior developers could see senior decision-making in real time and senior developers had to articulate their reasoning out loud. Used code reviews as teaching moments: every MR comment that flagged a pattern issue came with a short rationale and, where useful, a link to the relevant section of the architecture docs or CLAUDE.md context file. Set up a rotation so different developers led KT sessions over time, which forced deeper understanding and surfaced gaps. Tracked which architectural topics had been covered and which developers had led sessions, so coverage was visible rather than vibes-based. Mentored individual developers one-on-one on career-relevant skills — prompt engineering, spec-first workflows, AI-augmented code review — that translated beyond the contract.

Technologies

ASP.NET Core .NET 9 C# Clean Architecture CQRS / MediatR Entity Framework Core GitLab merge requests Markdown TDDs and ADRs Claude Code GitHub Copilot Azure services xUnit

Impact & Results

Built a team that could ship Clean Architecture .NET features at a consistent quality bar rather than a per-developer one. KT sessions and mob-coding gave the team a shared mental model of the ELA platform, which cut down on architecture-drift comments in code review and made onboarding new tickets faster. Code review shifted from gatekeeping to teaching, which raised the floor on code quality without slowing throughput. The rotation of session leadership built bench depth — more than one person could explain any given subsystem — which mattered on a federal platform where bus-factor risk was real. Mentorship deliverables (AI-native workflow, spec-first practice) gave team members skills that ported beyond the engagement.

5-developer team aligned on Clean Architecture and CQRS conventions

Weekly KT cadence established and maintained across the engagement

Mob-coding sessions used as the default forum for tricky architectural decisions

Session leadership rotated across the team to build bench depth

Code review used as a teaching channel with rationale on pattern-level feedback

Time-to-productive on new tickets reduced as shared mental model formed

This entry is public
0 Likes
0 Vouches

Vouches (0)

Vouches verify the authenticity of this work. Each voucher explains their connection to the work.

Loading vouches...