Benjamin Johnston — Systems Engineer

Columbus, Ohio, USA

Welcome! I build tools, libraries, and automation that reduce friction, simplify complex workflows, and make systems easier to extend and rely on.

My work spans native and managed environments, with a strong focus on turning messy or repetitive processes into rule-based, durable products.

Eliminated 95% of manual contractor effort via workflow automation

Built AutoHandshake! — a Selenium-based RPA suite with failure recovery and full audit trails that reduced manual annotation and triage by 95% across 400+ contractor hours. Recognized with Handshake's Model Validation 2 — Expert credential.

Evaluated search relevance and LLM responses at scale

Assessed query-result quality and multimodal AI outputs for RWS Group and Handshake, applying structured rubrics and benchmark design to improve ranking accuracy and model behavior.

Built production-ready SDKs and developer tooling

Google-SDK and Intuit provide strongly typed APIs for Drive integration and LLM endpoints, replacing fragile JSON shims with reusable, auto-refreshing clients for production workflows.

Languages

Fluent
C# D C x86
Intermediate
C++ Python Ruby JavaScript Bash VB.Net
Novice
z80

Technical Skills

Automation & RPA
Selenium Browser Automation RPA WebSocket
QA & Evaluation
Search Quality Evaluation Model Validation Benchmark Design Rubric-Based Assessment
API & Integration
OAuth HTTP REST JSON
Tooling & SDKs
SDK Engineering Developer Tooling CI/CD
Systems & Performance
SIMD/AVX JIT Compilation Metaprogramming
Graphics & UI
GTK4 Cairo 3D Visualization
AI & ML
LLM Integration Embeddings Streaming
Interop
D/C# Bridge CLR Internals

Platforms & Tools

Platforms
Windows Linux (Fedora/Arch) Embedded Linux
Development
Git GDB CMake CI/CD
Analysis
IDA Pro Ghidra Intel VTune AMD uPerf
Web
Nokogiri GTK

Domains

Workflow Automation RPA QA & Evaluation Search Quality Model Validation Developer Tooling SDK Engineering API Design Systems Internals Performance Engineering Data Processing SQL Reverse Engineering
Chemica

Chemica II: identity, integration, and one shared Page type

How Akashi unifies five disparate scientific data sources behind one lazy-fetching Page type in D, and why picking a single identity anchor early matters more than any clever parser.

Chemica I: a GTK-based PubChem wiki app with 3D molecular viewing

GTK4 application architecture in D, a custom Cairo-based 3D molecular viewer, PubChem compound search, article rendering with collapsible panels, and dosage aggregation with multi-dimensional similarity matching.

Selenium

Modernizing Selenium Support in D

WebKit GTK is abandoned on Windows, so I needed a cross-platform browser engine for Insurgent. D had no working Selenium bindings, so I forked a 2018 JsonWire library and brought it up to W3C WebDriver.

Selenium II: dispatch-oriented browser automation

Replacing fragile linear click-and-sleep scripts with an observable state machine and event dispatch queue. Stale-element errors went from constant to almost never.

Selenium I: automating multi-page workflows with Ruby and Selenium

Building a robust Ruby automation from 500 to 700 lines with explicit waits, DOM-driven state machines, CDP hooks, layered retry logic, and modular page objects.

Semantic retrieval on laptops: embeddings, centroids, and SIMD

Running embedding-based search on consumer hardware with two-stage centroid pruning, AVX-optimized dot products, and int8 quantization to keep the working set in cache instead of on disk.

Hacking C#: dynamic syscall stubs and user-mode hook detection

An educational walkthrough of syscall-ID extraction, shellcode stub generation, and hook taxonomy in C# on Windows, built on top of CoreCLR internal structures.

Experience