Senior API & Data Engineer

Below is a ready‑to‑use cover‑letter template (and a brief résumé outline) that you can customize for the Senior API & Data Engineer role at Penguin Random House (Job ID 287985).
Feel free to edit the highlighted sections with your own details, achievements, and metrics.

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📄 Cover‑Letter (PDF‑ready)

[Your Name]
[Your Street Address]
[City, State ZIP]
[Phone] • [Email] • [LinkedIn] • [GitHub]

April 8, 2026

Hiring Committee – API, Middle Tier & Mobile Team
Penguin Random House LLC
[Company Address – optional]

Dear Hiring Committee,

I am excited to submit my application for the **Senior API & Data Engineer** position (Job ID 287985). With **7+ years** of experience designing, building, and operating large‑scale data pipelines and RESTful services across **Oracle, PostgreSQL, and MySQL**, I have a proven track record of turning “source‑of‑truth” data models into reliable, high‑performance APIs that power mission‑critical business processes. The opportunity to modernize Penguin Random House’s Metadata API ecosystem while stewarding its legacy Java platform aligns perfectly with my blend of **backend engineering, data‑architecture, and cloud‑native delivery** expertise.

### Why I’m a strong fit

| Requirement | My Experience & Impact |
|-------------|------------------------|
| **5+ years of backend/data engineering with strong SQL** | • 7 years building complex relational schemas and stored procedures in Oracle (PL/SQL), PostgreSQL (PL/pgSQL) and MySQL. <br>• Optimized a cross‑system reporting query set (≈ 30 M rows) that reduced runtime from **12 min → 45 sec** (≈ 96 % improvement). |
| **Design “source of truth” data models & ETL pipelines** | • Led the design of a canonical “Book‑Metadata” model that unified 12 downstream systems, eliminating data duplication and cutting nightly ETL windows by **40 %**. <br>• Implemented Airflow‑based pipelines with dbt transformations, ensuring schema‑drift detection and automated data‑quality alerts. |
| **Java & Python API development (JAX‑RS, FastAPI)** | • Maintained a legacy Java/JAX‑RS Metadata service serving > 2 M requests/day; introduced **circuit‑breaker** and **rate‑limiting** patterns that reduced error‑rate by 30 %. <br>• Built a new Python/FastAPI microservice for real‑time metadata enrichment, achieving **99.99 % SLA** in production. |
| **Cloud, containers, CI/CD** | • Migrated on‑prem ETL workloads to **AWS (ECS + RDS)** and containerized Java/Python services with Docker & Kubernetes. <br>• Set up GitHub Actions pipelines that run unit, integration, and contract tests on every PR, cutting release lead‑time from 2 weeks → 2 days. |
| **Cross‑functional collaboration & downstream impact analysis** | • Partnered with product, editorial, and analytics teams to map data lineage, producing a **visual impact matrix** that is now used in every schema‑change request. <br>• Conducted post‑mortems for API incidents, driving process improvements that lowered mean‑time‑to‑recovery (MTTR) by 45 %. |

### What I’ll bring to Penguin Random House

* **Strategic modernization** – A phased roadmap that preserves the stability of the existing Java API while incrementally migrating high‑value endpoints to FastAPI, leveraging shared OpenAPI contracts and automated contract testing.  
* **Robust data governance** – End‑to‑end lineage tracking, automated schema‑validation, and data‑quality dashboards that give product owners confidence in downstream releases.  
* **Scalable, cost‑effective architecture** – Right‑sizing of RDS instances, use of read‑replicas, and serverless compute (AWS Lambda) for bursty metadata look‑ups, delivering performance gains without inflating cloud spend.  

I am inspired by Penguin Random House’s commitment to quality, innovation, and diversity, and I am eager to help the Publishing Applications Group deliver a next‑generation Metadata API that fuels both internal workflows and external partner experiences.

Thank you for considering my application. I look forward to the opportunity to discuss how my background, technical vision, and collaborative style can contribute to the continued success of Penguin Random House.

Sincerely,

[Your Name]

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📑 One‑Page Résumé Outline (ATS‑friendly)

Header – Name, phone, email, LinkedIn, GitHub (optional)

Professional Summary (2‑3 lines)

Senior API & Data Engineer with 7 + years of experience designing relational data models, building high‑throughput Java and Python APIs, and orchestrating cloud‑native ETL pipelines. Proven ability to modernize legacy systems while ensuring data integrity, scalability, and rapid delivery.

Core Competencies (bullet list, 8‑10 items)

• Relational DB design (Oracle, PostgreSQL, MySQL)
• Java (JAX‑RS, Spring) & Python (FastAPI, Flask)
• ETL orchestration (Airflow, dbt, Talend)
• Data modeling & “source‑of‑truth” architecture
• Cloud platforms (AWS, GCP) & Kubernetes
• CI/CD (GitHub Actions, Jenkins, Docker)
• API contract testing (OpenAPI, Pact)
• Performance tuning & query optimization
• Monitoring & observability (Prometheus, Grafana, ELK)
• Cross‑functional stakeholder management

Professional Experience

Senior Data Engineer – XYZ Publishing, New York, NY
Jan 2022 – Present

• Designed a unified metadata schema across Oracle, PostgreSQL, and MySQL; reduced data‑reconciliation effort by 35 %.
• Maintained legacy Java/JAX‑RS Metadata service (2 M req/day) and introduced FastAPI microservice for real‑time enrichment, achieving 99.99 % SLA.
• Built Airflow pipelines with dbt transformations; automated schema‑drift detection saved 15 h/week of manual QA.
• Migrated services to AWS ECS + RDS; cut infrastructure cost by 22 % while improving latency by 40 %.

Data Engineer – ABC Media, Boston, MA
Jun 2018 – Dec 2021

• Developed PL/SQL stored procedures for high‑volume reporting; query runtime cut from 12 min to 45 sec.
• Implemented CI/CD pipelines with Jenkins & Docker; reduced release cycle from 2 weeks to 2 days.
• Partnered with product owners to map data lineage; created impact‑analysis framework used for all schema changes.

Software Engineer – DEF Solutions, Remote
Jul 2015 – May 2018

• Built RESTful Java services (JAX‑RS) for internal tooling; introduced circuit‑breaker pattern, decreasing error rates by 30 %.
• Created Python scripts for data migration between MySQL and PostgreSQL, handling > 100 M rows with zero data loss.

Education

B.S. Computer Science – University of Washington, Seattle, WA – 2015

Certifications (optional)

• AWS Certified Solutions Architect – Associate (2023)
• Oracle Database SQL Certified Associate (2021)

Publications / Open‑Source (optional)

• Contributor, fastapi‑metadata‑service (GitHub, 2024) – 1.2k stars, used by 12 internal teams.

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How to Use This Material

1. Copy the cover‑letter into a word processor, replace the bracketed placeholders ([Your Name], [Phone], etc.) with your personal info, and tweak any bullet points to reflect your exact numbers and achievements.
2. Export the cover‑letter as PDF (keep the formatting clean; avoid fancy fonts).
3. Populate the résumé outline with your own dates, company names, and quantifiable results. Keep the layout simple (single column, standard fonts like Calibri or Arial, 10‑11 pt).
4. Submit both files through the Penguin Random House careers portal before the April 21 deadline.

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Quick Checklist Before Submitting

• ☐ All personal contact info is up‑to‑date.
• ☐ Quantitative metrics (percentages, request counts, latency improvements) are accurate and verifiable.
• ☐ Keywords from the job posting (e.g., “Oracle”, “FastAPI”, “ETL”, “Kubernetes”, “CI/CD”) appear naturally in both documents.
• ☐ No spelling or grammar errors (run a final spell‑check).
• ☐ PDF files are under 2 MB and named FirstLast_CoverLetter.pdf & FirstLast_Resume.pdf.

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If you’d like a deeper review of your existing résumé, help tailoring any of the bullet points, or want to practice interview questions specific to this role (e.g., schema‑migration strategy, API versioning, data‑lineage tools), just let me know—I’m happy to dive in! Good luck, and I’m confident you’ll make a strong impression on the Penguin Random House hiring team. 🚀