Allen Gary Grimm, Developer in Durham, NC, United States
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Allen Gary Grimm

Python Developer

Durham, NC, United States

Toptal member since November 5, 2014

Bio

Allen is a machine learning architect with 15 years of experience, specializing in the integration of machine learning and data engineering. He focuses on solving business problems by aligning technology with system architecture, managing the entire journey from ideation through development and into production.

Portfolio

Bond Capital Management, LP
Python, Apache Airflow, PostgreSQL, Data Modeling, Management, SQL, Snowflake...
CVS
Python, PySpark, Databricks, Apache Airflow, MLflow, Decision Trees...
Grimm Science
Amazon Web Services (AWS), DigitalOcean, Google Cloud, Agile, Machine Learning...

Experience

  • Machine Learning Algorithms - 15 years
  • Python - 15 years
  • Agile Data Science - 10 years
  • Machine Learning Operations (MLOps) - 8 years
  • Software Architecture - 6 years
  • SQL - 6 years
  • Test-driven Development (TDD) - 6 years
  • Uplift Modeling - 3 years

Preferred Environment

Git, Python, SQL, Data Build Tool (dbt)

The most amazing...

...system I built is an enterprise-grade ML pipeline tracking all observable startups, rendering leads provably predictive of future high-quality VC opportunities.

Work Experience

Machine Learning Architect, Contractor

2021 - 2026
Bond Capital Management, LP
  • Inherited and refactored a rule-based lead generation system from raw SQL into a maintainable dbt-native architecture, and then graduated the rule-based engine into a proper supervised learning framework handling arbitrary models.
  • Identified a fundamental flaw in the team's core performance metric; defined, advocated for, and built an honest replacement grounded in real-world company recall --- which became the de facto language for team performance discussions.
  • Rebuilt lead publication into a framework supporting arbitrary models with configurable lead strength thresholds and per-investor limits, monitored by internal tooling, response, and usage monitoring, deeply tracked by internal dashboards.
  • Designed and owned the weekly model retrain sequence, defining SLAs across each stage (raw data validation, feature materialization refresh, model retrain, backtest, and prediction generation) and serving as the human approval gate.
  • Architected the feature engineering pipeline that grew to 10+ external data integrations, processing 100+ raw features into nearly 1,000 model-ready features via stable layered dbt transformations in Snowflake.
  • Extended the core performance metric into four overlapping views (real-world and theoretical recall at the company level, real-world and theoretical precision at the lead level), which became the de facto framework for team performance discussions.
  • Modeled the central company object as an entity over time: a unified company table derived from company creation and terminating events to natively represent both existence and temporal scope, underpinning the entire ML pipeline.
  • Rearchitected our Affinity CRM integration: Included a code layer, including simple raw API commands up to classes streamlining specific workflows, a database layer within our pipelines, gracefully handling our dual-source-of-truth requirement.
  • Dedicated a final month to structured knowledge transfer: one-on-one sessions with all team members, collaborative brainstorms on open workstreams, and written documentation for all projects where expertise would otherwise be lost.
Technologies: Python, Apache Airflow, PostgreSQL, Data Modeling, Management, SQL, Snowflake, Alembic, SQLAlchemy, Prefect, Valohai, XGBoost, LightGBM, Logistic Regression, Feast, SHAP, LLM Integration, FineWeb, Comon Crawl, Data Build Tool (dbt), Affinity CRM, Crunchbase API, Matplotlib, Retool, Lucidchart, Asana, OLTP, OLAP, System Architecture

Senior Data Scientist and Data Engineer

2019 - 2021
CVS
  • Reduced uplift model runtime from eight hours to five minutes on the team's flagship initiative, across millions of rows and hundreds of features.
  • Advanced tree decision functions within the random forest architecture, compared to current best practices, lift average model performance by 50 BPS across the full data science team.
  • Packaged the uplift model as a versioned, pip-installable library for consistent team-wide use across pipelines.
  • Integrated with MLFlow to fit natively into the existing pipelines.
  • Refactored the experimentation pipeline in Airflow and PySpark to bring poorly scaling jobs back within SLA.
Technologies: Python, PySpark, Databricks, Apache Airflow, MLflow, Decision Trees, Gradient Boosted Trees, Azure, Uplift Modeling, A/B Testing, SQL

Founder, Engineer, and Data Scientist

2016 - 2019
Grimm Science
  • Achieved 80%+ precision on website spam detection and high-quality content identification across a full internet scrape, lifted from single-digit precision. Constrained modeling to regression, putting work on deep feature engineering.
  • Translated legal domain expertise into a full-stack case management platform. Formalized legal partner's litigation methodology, wrapped in an as-a-service white-label app.
  • Converted the Daedalus nanoparticle modeling software from MATLAB to Python, used to construct DNA scaffold models from arbitrary 3D target shapes.
  • Built a job posting-to-candidate matching engine using TF-IDF and Doc2Vec to identify skill gaps and surface actionable guidance for candidates.
  • Built the core engine of a bidirectional recommender system mapping grocery products to users and users to products, delivering targeted marketing campaigns from sales data as a managed service to grocery store clients.
  • Integrated our CRM with Salesforce Marketing Cloud to sync customer data into clients' existing marketing workflows.
  • Deployed SCIP mixed integer programming solver as a managed service on AWS with long-running task management and a full API wrapper.
  • Built serverless data aggregation pipeline on AWS Lambda and S3 with Looker integration for dashboarding and video/metadata content categorization.
  • Prototyped predictive models for data cleaning and forecasting to streamline construction logistics.
Technologies: Amazon Web Services (AWS), DigitalOcean, Google Cloud, Agile, Machine Learning, Python, Amazon S3 (AWS S3), AWS Lambda, Amazon EC2, REST APIs, PySpark, Multi-armed Bandits (MABs), A/B Testing, Uplift Modeling, SQL, API Integration, CRM

Data Scientist and Web Developer

2016 - 2017
Doing, Inc.
  • Independently delivered end-to-end data science features, owning the process from ideation to back-end implementation.
  • Engineered an event canonicalization service to deduplicate and unify events scraped across platforms. Custom sparse data-tolerant graph algorithm, written to gracefully update on ever-growing data.
  • Built tag extraction and categorization pipelines to surface concise, descriptive metadata for events. A combination of Doc2Vec and TF-IDF balanced content awareness with keyword salience.
  • Prototyped a cold-start event recommendation engine to bootstrap the app from zero user data into mainstream usage.
Technologies: Doc2Vec, Graph Theory, Neural Networks, Tf-idf, SQLAlchemy, Python, Amazon S3 (AWS S3), System Architecture

Senior Data Scientist

2014 - 2016
Veelo
  • Designed a topic-based relevance model aggregating tag-derived content similarity and usage-derived quality signals into a unified relevance score powering content sorting, recommendations, and search indices.
  • Built a tag model extracting two complementary tag sets: one from direct NLP on content, one propagated from user profiles into consumed content.
  • Expanded the search engine to include spellcheck, tag-based faceting, and live autocomplete.
  • Redesigned the permission query powering arbitrary organizational hierarchies from a recursive relational structure to a native graph query in Neo4j. Identified the need, wrote a poc to make my case, and used it to drive our system recovery.
  • Audited client-facing admin dashboards and available data to identify reporting gaps, then progressively owned their implementation: from simple component edits up to building entire new dashboard sections.
  • Developed within a test-driven development and agile workflow.
Technologies: Django REST Framework, SQLAlchemy, Apache Solr, Haystack, Git, Django, Python, REST APIs, SQL, Elasticsearch, System Architecture

Data Scientist

2014 - 2014
Cloudability (via Grimm Science)
  • Surveyed time series prediction methods.
  • Conducted a case study on time series prediction applied to server usage in R.
  • Wrote product-quality implementation of the chosen time series model (holt winters) from scratch in Python.
  • Calibrated forecasting intervals (expected accuracy on predictions) in terms of performance, and trained and tested sets of data.
  • Documented model implementation and testing procedures to enable the client's engineering team to build the model into their dashboard.
Technologies: R, Python

Senior Data Scientist

2014 - 2014
Sovolve (via Grimm Science)
  • Modeled user activity and interactions to optimize the user experience by filtering content to what is likely to be the most interesting and useful.
  • Helped build out back-end data infrastructure to improve app performance and prepare for scalability.
  • Conducted A/B studies to help with product decisions.
  • Clustered user behavior into distinct and comprehensible segments.
  • Conducted and internally published the app's virality to report product success and direct product decisions.
Technologies: Mixpanel, Neo4j, PostgreSQL, Python, Linux, REST APIs

Data Scientist

2012 - 2014
PlayHaven
  • Modeled and predicted user behavior in mobile games. Core projects included churn prediction and user path prediction.
  • Managed relations between data science and engineering to catalyze productization of initiatives.
  • Conducted ad hoc advanced analytics to assist in product decisions and to seed ideas for future data modeling.
  • Rebuilt system logs: Solved for errors in observed device identifiers and marked invalid log entries as such. More precisely, the task was to write an iterative mapreduce algorithm to solve for all connected components in a several-billion node network using Hadoop Streaming and Python.
  • Recruited, trained, and managed small teams of interns to assist with projects.
Technologies: Hadoop, R, GitHub, Python, Linux, Amazon S3 (AWS S3), Amazon EC2, REST APIs

Data Miner, Software Engineer, and Data Engineer

2011 - 2012
Nike Sport Research Lab
  • Demoed data mining.
  • Defined roles for new full-time data miners in a lab.
  • Created a database architecture to centralize the lab's data collection and analysis.
  • Worked with researchers to import their personal research data into a consistent format.
  • Liaised with lab researchers and the Wolfram team to build the centralized database.
Technologies: MySQL, Python, C++, REST APIs

Research Assistant

2010 - 2011
Portland State University - Teuscher Lab
  • Built an evolutionary algorithm in C++ using the library ParadisEO to evolve complex networks.
  • Wrote a network evaluation utility to simulate traffic and calculate other metrics on networks representing massively parallel processors with non-traditional interconnections.
  • Built out and documented the experimentation process to enable fellow researchers within and outside of the university to use my framework.
  • Conducted experiments relating the properties of links to the types of networks it would optimally be used in.
  • Wrote a thesis on creation of a framework and the results of initial experiments.
Technologies: Network Analysis, Simulations, Evolutionary Algorithms, ParadisEO, C++, Linux

Experience

Production ML System for VC Lead Generation

Serving as the technical anchor of a flat, collaborative team, I continuously architected new components of a production ML pipeline, each fitting into a growing system I was increasingly the connective tissue of. The pipeline grew to include 10+ external data integrations, processed into nearly 1,000 model-ready features; weekly model retrains with a four-tier versioning system; a human-gated approval process before each model release; and a lead publication framework supporting arbitrary models with configurable thresholds. Over four years, we grew from under 5% to over 85% recall across the full upstream private company space, approaching the theoretical upper limit of what the data could support, and covering the near-entirety of the investment universe relevant to a growth-stage VC firm.

Veelo — Recursive Relational to Native Graph Query

Identified an exponentially scaling recursive join pattern powering our multi-tenant permission system and flagged it as a projected failure at scale. Built a proof-of-concept graph query in Neo4j demonstrating orders-of-magnitude performance gains with linear scalability, but couldn't get organizational traction until the system failed as projected. Led the engineering team through the recovery sprint using my POC as the foundation, migrating the production permission system to the graph-native architecture.

Mix Tech — Website Spam Detection Through Feature Engineering

Achieved 80%+ precision on website spam detection and high-quality content identification across a full internet scrape — starting from single-digit precision — by deliberately constraining the model to logistic and linear regression and placing the full burden of performance on feature quality. Engineered rich document features using Word2Vec aggregated into varying Doc2Vec shapes to capture content and integrity signals. The constraint was intentional: rather than chasing model complexity, we proved that disciplined feature engineering over simple models could outperform sophisticated models built on weak features, while keeping minimal compute requirements and enabling reusable feature discoveries across the organization's broader work. It permanently changed how I approach data science problems.

PlayHaven — Cross-platform Identity Resolution

Built a cross-platform identity resolution system merging available user identifiers into a unified identifier with higher fidelity and cohesion across apps and platforms. Publishers supplied initial links between internal IDs and device identifiers, seeding an iterative MapReduce process that derived connected components across all publishers. Careful filtering of edge cases produced a clean unified identifier — the first instance of a canonicalization pattern that became a recurring thread across my career, reappearing at Doing Inc, the Personal Finance Genome Project, and BOND Capital.

Doing Inc — Event Canonicalization Service

Engineered a standalone service to deduplicate and canonicalize events scraped across multiple hosting platforms, where hosts commonly posted the same event on Meetup, Eventbrite, and others simultaneously. Designed complementary distance functions across event attributes to handle sparse and inconsistent records, constructed a matching graph filtered to connected components as candidate duplicate sets, and applied calibrated matching algorithms guided by curated edge cases to resolve sub-graphs into distinct canonical events. Formalized all possible identity mutation rules to support dynamic updates as new scrape data arrived, then delivered the whole system as a regularly-scheduled back-end service built with test-driven development.

Education

2009 - 2011

Master of Science Degree in Computational Intelligence (EE Specialization)

Portland State University - Portland, Oregon

2005 - 2009

Bachelor of Science Degree in Electrical Engineering

Gannon University - Erie, Pennsylvania

Skills

Libraries/APIs

Scikit-learn, SQLAlchemy, Django ORM, Matplotlib, PySpark, REST APIs, Pandas, XGBoost, Crunchbase API, Spark ML

Tools

IPython Notebook, Apache Solr, Haystack, Git, GitHub, Apache Airflow, Docker Compose, Doc2Vec, Vagrant, Occam3, MATLAB, Boto 3, Prefect, Retool, Lucidchart, Asana

Languages

Python, SQL, HTML, C++, C, R, Octave, JavaScript, Snowflake, Scala

Frameworks

Multi-armed Bandits (MABs), Django, ParadisEO, Django REST Framework, Angular, Apache Spark, Hadoop, Flask, Alembic, LightGBM, Spark

Platforms

Linux, AWS Lambda, Amazon EC2, Docker, Mixpanel, DigitalOcean, Windows, AWS Elastic Beanstalk, Amazon Web Services (AWS), Databricks, Azure, Kubernetes, Valohai

Paradigms

Test-driven Development (TDD), Agile Software Development, Agile, Management, OLAP, MapReduce

Storage

PostgreSQL, MySQL, Amazon DynamoDB, NoSQL, Redshift, Column-oriented DBMS, Neo4j, HDFS, Amazon S3 (AWS S3), Elasticsearch, Google Cloud, OLTP, Graph Databases, Relational Databases

Other

Agile Data Science, Decision Trees, Random Forests, Neural Networks, Cython, Data Science, Uplift Modeling, Machine Learning Operations (MLOps), A/B Testing, Data Build Tool (dbt), CRM, Software Architecture, Machine Learning Algorithms, Simulated Annealing, Graphical Models, Evolutionary Algorithms, Markov Model, Feast, Simulations, Network Analysis, Tf-idf, Graph Theory, Machine Learning, SVMs, Regression, Lambda Functions, Mixed-integer Linear Programming, MLflow, Gradient Boosted Trees, Data Modeling, Architecture, API Integration, Logistic Regression, SHAP, LLM Integration, FineWeb, Comon Crawl, Affinity CRM, System Architecture, Stochastic Search, Experimental Design, Process Simulation, System on a Chip, Large Language Models (LLMs), Unsupervised Learning, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Information Retrieval, Algorithmic Graph Theory, Data Engineering, APIs

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