Pipelines · Schemas · Scale

I build the systems
data moves through.

Five years building schemas, ingestion pipelines and transformation systems — the layer that turns encrypted flat files, field surveys and GIS exports into something a reporting stack can trust. Alden Systems now, Medallia before that. Maths degree, which mostly shows up as refusing to ship a pipeline I can't reason about.

charles@birmingham: ~
$ cat profile.json
{
  "role":      "Data Engineer",
  "focus":     ["schemas", "ingestion", "transformation"],
  "scale":     { "records": 4_000_000, "hierarchy": 166_000 },
  "stack":     ["Python", "SQL", "MongoDB", "SFTP"],
  "degree":    "B.S. Mathematics",
  "employer":  "Alden Systems",
  "since":     2021
}
$ _
4M+Survey records
under schema
166K+Employee records
into hierarchies
−30%Time complexity
on core systems
−23%System
load time

01 — How I build

Correctness first, then
everything else.

  • 01

    Start at the schema. How a record is parsed, structured, stored and read downstream is the contract. Get it wrong and every query after it is a workaround — so the schema is designed before the pipeline, not discovered by it.

  • 02

    Automate the boring, dangerous parts. Fetching, decrypting and parsing files by hand is where data quietly goes missing. If a step happens weekly, it belongs in code — fetch → decrypt → parse → load, unattended.

  • 03

    Reconcile, don't assume. A pipeline that runs without error is not the same as a pipeline that moved everything. Counts in, counts out, and a way to prove it.

  • 04

    Profile before optimizing. The bottleneck is rarely where it feels like it is. Measure, then fix the complexity — that's how -30% time complexity and -23% load time happened, rather than by guessing.

  • 05

    Translate, don't relay. Utilities and product owners describe outcomes, not constraints. Turning "the pole owner needs this" into something a pipeline can actually enforce is most of the job — and skipping it is how systems get built twice.

SFTP feed enterprise source decrypt flat files parse + validate transform hierarchy · accounts MongoDB document schema reporting analytics layer reconcile — counts in vs. counts out

// ingestion path built at Medallia — unattended, scheduled, reconciled

02 — Selected work

01 MEDALLIA 2023 – 2025

Document schemas & importers for 4M+ survey records

Architected the document schemas and data importers governing how millions of incoming survey records were parsed, structured, stored and accessed by every downstream analytics workflow. The schema was the contract — get it right and the analytics layer stops being a guessing game.

Input
survey records
Design
document schema + importers
Store
MongoDB
Scale
4,000,000+
  • 4M+ RECORDS
  • MongoDB
  • Schema design
  • Data modeling
  • Analytics enablement
02 MEDALLIA 2023 – 2025

Automated encrypted SFTP ingestion

Designed ingestion workflows that fetch, decrypt and parse flat files from enterprise sources straight into MongoDB collections — removing a manual, error-prone handoff and turning a recurring chore into infrastructure nobody has to think about.

Source
enterprise SFTP
Steps
fetch → decrypt → parse
Sink
MongoDB collections
Mode
unattended
  • SFTP
  • Decryption
  • Flat-file parsing
  • Ingestion automation
  • MongoDB
03 MEDALLIA 2021 – 2023

Organizational hierarchies from 166K+ employee records

Orchestrated upstream ingestion from client SFTP feeds, processing 166,000+ employee records into organizational hierarchy structures that client-facing reporting systems depend on — then built the transformation pipelines integrating hierarchy and account data for scoped feedback analysis and action planning.

Input
client SFTP feeds
Build
org hierarchy structures
Output
client-facing reporting
Scale
166,000+ records
  • 166K+ RECORDS
  • Hierarchy construction
  • ETL
  • Reporting systems
04 MEDALLIA 2021 – 2023

Algorithmic and performance optimization

Administered and optimized the data structures and algorithms behind core systems, cutting time complexity by 30%, and reduced system load time by 23% using efficient cloud-based technologies. The kind of work where the win is measured in what users stop noticing.

Target
core system algorithms
Method
profile → restructure
Complexity
−30%
Load time
−23%
  • −30% COMPLEXITY
  • −23% LOAD TIME
  • Data structures
  • Algorithms
  • Profiling
05 ALDEN SYSTEMS 2025 – now

Field & GIS asset data at utility scale

Engineering and synthesizing large-scale asset datasets from multiple sources — turning raw field and GIS data into clean, structured outputs for utility asset management. Translating requirements from pole owners and power utilities into workflows, and owning continuous improvement across the AldenOne transformation pipelines through to UAT signoff.

Input
field + GIS exports
Process
AldenOne pipelines
Output
structured asset data
Gate
UAT signoff
  • GIS
  • Field data
  • Transformation pipelines
  • Data integrity
  • UAT

03 — Stack

Languages
PythonSQL / T-SQLJavaScript TypeScriptBashHTMLCSS
Data stores
MongoDBSQL ServerPostgreSQLMySQL Document schema designIndexingQuery tuning
Pipelines
Ingestion automationSFTP fetch / decrypt / parseFlat-file & API parsing Transformation pipelinesHierarchy constructionBatch schedulingReconciliation
Platform
Cloud data servicesREST APIsGitPostmanJiraUAT & release validation
Foundations
Data structures & algorithmsComplexity analysisPerformance profiling GIS / geospatialProof-based reasoningTechnical specification

04 — Path

  • Dec 2025 →

    Product Specialist / Data Engineer · Alden SystemsCurrent

    Birmingham, AL — field and GIS asset data, AldenOne transformation pipelines, cross-functional delivery through UAT.

  • Jul 2023 – Nov 2025

    Senior Technical Analyst · Medallia

    Birmingham, AL — document schemas and importers at 4M+ record scale, automated SFTP ingestion into MongoDB, mentoring junior analysts on architecture and implementation.

  • Jul 2021 – Jul 2023

    Technical Analyst · Medallia

    Birmingham, AL — org-hierarchy construction from client SFTP feeds, transformation pipelines into reporting, algorithmic and load-time optimization.

  • 2017 – 2021

    B.S. Mathematics · Birmingham-Southern College

    Aug 2017 – May 2021.

05 — Contact

Let's build something
that doesn't drop records.

Open to data engineering, pipeline and platform work — and happy to talk schemas with anyone who has strong opinions about them.