Crystal J. Hollis

01/26/2026

Exploring Data Engineering: Skills and Mindset Shift

As I work through this course, I keep coming back to the idea that data engineering is not neutral. The decisions made at this layer, how data is collected, cleaned, structured, stored, and surfaced, shape everything that comes after. They influence which stories get told, which populations are visible, and which outcomes are even possible to measure....

As I work through this course, I keep coming back to the idea that data engineering is not neutral. The decisions made at this layer, how data is collected, cleaned, structured, stored, and surface…

05/29/2025

Y'all, I gave a commencement speech for Dallas College STEM League! 😳

Not gonna lie—I was nervous, low on sleep, and didn't have enough time to practice. I stumbled in places. At one point, it even looks like I hid behind my paper. But I showed up, and I shared something I know well: resilience.

This month, I officially completed my Python Developer Certificate at Dallas College. I also earned my STEM League pin, cord, and certificate after racking up over 1,000 points attending workshops, events, and networking sessions.

STEM League challenged me to get out of my comfort zone and step into the world of data science, AI, and public health. It helped me see that I do belong in this space—even as a creative, even as a mom, even with setbacks.

✅ I didn’t get into the Ph.D. program I applied for. That stung.
But I'm not giving up on the goal—I'm already planning my next move.
✅ I’ve dropped or failed classes during the program.
But I kept going. I got better each time. Made Provost's honor roll this Spring semester!
✅ I doubted I’d ever belong in STEM.
But now I’m writing Python, applying for data analyst roles, and speaking at graduations.

This speech was more than a reflection—it was a declaration: "You’re allowed to pivot. You’re allowed to rest. You’re allowed to fail and still be worthy. You’re allowed to dream out loud—even while you’re still figuring things out."

If you're in a season of transition, I hope this reminds you that progress doesn't have to be perfect.

Thanks again to Ms. Fabiola Resendiz, Dr. Neda Saffarian Tousi (Hozhabri), PhD , Erick Flores-Ortega , and Dr. Jason Treadway for the honor and support.

Here's to every setback that became a plot twist.

Congrats to STEM League Class of 2025!

hashtag hashtag hashtag hashtag hashtag hashtag hashtag hashtag hashtag hashtag

05/29/2025

Updated my Portfolio: https://crystaljhollis.com/

After lots of polishing, coding, and reorganizing, I’m excited to share that my portfolio website is now live and fully updated!

Changelog:

- Added my latest projects in data science, automation, GIS, and health analytics

- Updated my educational journey through Dallas College and UNT, linking to course descriptions, GitHub repos, and project samples

- Certifications in Python, Machine Learning, and more

This site reflects not only my growth as a developer and data storyteller—but also my passion for using tech to make an impact in public health, ethical AI, and accessibility.

I’d love feedback, collaboration, or even just a quick visit. Thanks for supporting my journey!

I’m passionate about using data science and AI to tackle public health challenges, misinformation, and health disparities. With a foundation in multimedia, GIS, and machine learning, I aim to build accessible, ethical solutions for real-world impact.

02/20/2025

Thank you, Nicholas Wagner, for speaking with us at Dallas College STEM League during Engineer’s Week!

Your journey from self-doubt in math to becoming a Software Engineer at Lockheed Martin was truly inspiring. Hearing about how you once thought math wasn’t for you—only to later embrace engineering and succeed in a technical field—resonated with me. I also didn’t do so well in high school math, or at least I thought, but your story reminded me that persistence and learning from failure matter more than where we start.

Key Takeaways from Nick's Talk:

🔹 Lifelong Learning is Key
"𝘊𝘰𝘯𝘵𝘪𝘯𝘶𝘦 𝘵𝘰 𝘣𝘦 𝘤𝘶𝘳𝘪𝘰𝘶𝘴 𝘢𝘣𝘰𝘶𝘵 𝘸𝘩𝘢𝘵'𝘴 𝘰𝘶𝘵 𝘵𝘩𝘦𝘳𝘦 𝘢𝘯𝘥 𝘯𝘦𝘷𝘦𝘳 𝘭𝘦𝘵 𝘢𝘯𝘺 𝘦𝘹𝘵𝘦𝘳𝘯𝘢𝘭 𝘧𝘢𝘤𝘵𝘰𝘳𝘴 𝘥𝘢𝘮𝘱𝘦𝘯 𝘺𝘰𝘶𝘳 𝘤𝘶𝘳𝘪𝘰𝘴𝘪𝘵𝘺 𝘢𝘯𝘥 𝘺𝘰𝘶𝘳 𝘱𝘢𝘵𝘩 𝘰𝘧 𝘭𝘦𝘢𝘳𝘯𝘪𝘯𝘨."

🔹 Real-World Projects Matter More Than Just Classes
Nick emphasized the importance of working on projects that showcase your skills. Hiring managers care about what you build and solve, not just what’s on your transcript.

🔹 Internships Can Help You Find What You Don’t Want To Do
Trying things out is just as valuable as knowing what you want upfront.

🔹 The STAR Method for Interviews
Nick stressed practicing the STAR (Situation, Task, Action, Result) method for interviews. Employers want to hear about how you solved real problems, not just generic responses.

🔹 Networking & Mentorship Matter
Building strong relationships with mentors and professionals can open doors.

🔹 You Don’t Have To Be a Genius in Math To Succeed in Engineering
"𝘐 𝘯𝘦𝘷𝘦𝘳 𝘵𝘩𝘰𝘶𝘨𝘩𝘵 𝘐 𝘸𝘰𝘶𝘭𝘥 𝘣𝘦 𝘢𝘯 𝘦𝘯𝘨𝘪𝘯𝘦𝘦𝘳𝘪𝘯𝘨 𝘴𝘵𝘶𝘥𝘦𝘯𝘵. 𝘉𝘶𝘵 𝘐 𝘴𝘵𝘢𝘺𝘦𝘥 𝘤𝘶𝘳𝘪𝘰𝘶𝘴, 𝘸𝘰𝘳𝘬𝘦𝘥 𝘩𝘢𝘳𝘥, 𝘢𝘯𝘥 𝘯𝘰𝘸 𝘐 𝘨𝘦𝘵 𝘵𝘰 𝘸𝘰𝘳𝘬 𝘰𝘯 𝘴𝘰𝘧𝘵𝘸𝘢𝘳𝘦 𝘧𝘰𝘳 𝘧𝘪𝘨𝘩𝘵𝘦𝘳 𝘫𝘦𝘵𝘴."

After hearing Nick’s talk, I’m motivated to:

✔ Work on more projects that demonstrate my skills in GIS, AI, and data science.

✔ Practice interview techniques, including the STAR method, to confidently explain my work.

✔ Stay curious and explore different fields, just like Nick did, to find where I fit best.

Thank you again, Nick, for sharing your journey and insights!

02/20/2025

Huge thanks to Sarah Peña for sharing her career journey and insights during Dallas College STEM League Engineers Week! Your advice on navigating careers in engineering, networking, and professional growth was invaluable.

Key takeaways from Sarah’s talk:

🔹 The Three E’s: Education, Experience, Exposure – Career growth isn’t just about what you know but also who knows you and what you can do. Keep learning, gaining experience, and building your network.

🔹 Your first job (or internship) doesn’t define your career – Sarah’s first internship helped her realize what she didn’t want to do. It’s just as important to figure out what doesn’t work for you as it is to find what does.

🔹 Self-advocacy is key – You bring value to a company, and it’s important to speak up, build relationships, and seek mentorship.

🔹 Certifications & further education – Don’t rush into extra degrees or certifications. Let your degree take you as far as it can, and if you need more, your company may even pay for it.

🔹 Networking is everything – Internal networking can open doors for promotions, while external networking helps you explore new industries and career shifts.

🔹 Finding the right company fit matters – Consider mentorship programs, education benefits, work-life balance, and growth opportunities when choosing a company.

🔹 “If you don’t know where you’re going, you’ll never arrive.” – Even if your career path isn’t fully clear yet, start setting goals and adjusting them as you grow.

This was a fantastic discussion, and I appreciate the opportunity to learn from it.

02/20/2025

This week is Engineers Week at Dallas College hosted by STEM League and the STEM Institute.

Kyle Blessing, Quality Engineer at Lockheed Martin, shared valuable insights on career growth, engineering challenges, and workplace skills.

Key Takeaways from the Talk:
✔️ Internships matter—apply broadly and start early
✔️ Networking is essential—casual conversations can lead to opportunities
✔️ Technical skills help you stand out—Python, Excel, and data analysis are valuable
✔️ Communication is just as important as engineering skills
✔️ Work-life balance in industry is better than in school
✔️ Mechanical Engineering isn’t always hands-on—but you can find roles that are

I'm grateful for the opportunity to learn from Kyle’s experiences. I definitely want to keep improving my networking and communication skills, as well as asking the right questions.

02/18/2025

This week is Engineers Week at Dallas College hosted by STEM League and the STEM Institute. Today I listened to Maggie Wang, Ph.D. Candidate in Biomedical Engineering at UT Southwestern Medical Center. She provided valuable insights into navigating a Ph.D., balancing research with industry experience, and the role of AI in biomedical science. Her "CEO mindset" approach to structuring her day and making time for reading scientific news is something I definitely want to incorporate into my own routine.

A key takeaway was the importance of choosing an advisor who supports industry engagement. At UT Southwestern, Ph.D. students can take summer industry internships, but this requires advisor approval. Asking about this upfront ensures flexibility for those interested in biotech, AI in healthcare, or public health applications.

Maggie also emphasized the resilience needed in research—science rarely follows a straight path, and setbacks are inevitable. Staying connected to the broader impact of research, such as improving patient care or developing new technologies, helps maintain motivation through the long process of discovery.

Another important point was how research topics evolve. Ph.D. students typically start with a broad interest (e.g., cancer immunotherapy, AI in healthcare) and refine it through discussions with their adviser. Flexibility is essential, as unexpected findings often reshape research direction.

This discussion has encouraged me to refine my research focus and identify faculty working in AI-driven healthcare and public health applications.

02/13/2025

Tonight I attended the UT Southwestern O’Donnell School of Public Health Open House. I reconnected with familiar faces, got answers to tons of questions, and gained valuable insights into the Health Data Science program.

The faculty and students were welcoming, and the campus tour gave me a real sense of their environment. Leaving the event, I feel hopeful about my chances and even more excited about this next step in my journey!

02/06/2025

This year, I want to share key takeaways from my classes, lectures, and workshops. If the information helps someone in my network, that would be awesome! [Reposting from LinkedIn]

Today, I started the GIS Programming (GIS 2335) Spring 2025 course at Dallas College with a deep dive into Python for GIS and the evolving skill set needed in the industry.

What is GIS?
GIS (Geographic Information System) is a technology that captures, stores, analyzes, and visualizes spatial and geographic data to help understand patterns, relationships, and trends in various fields such as urban planning, environmental science, and public health.

Key Takeaways from today's lesson:

▪️ Python enables automation of GIS tasks, reducing manual work.
▪️ Scripting allows for batch processing across multiple maps and datasets.
▪️ While GIS tools offer built-in functions, Python enhances efficiency for large-scale analysis.
▪️ GIS technology evolves quickly—memorization is not the goal.
▪️ Understanding GIS concepts and learning to adapt to new tools is more valuable than rote learning.
▪️ Employers prioritize:
✔️ Problem-solving skills
✔️ Adaptability and research ability
✔️ Experience with automation and scripting

This class lays the foundation for developing hands-on experience and intuition in GIS programming. I'm excited to apply these skills in future projects!

02/06/2025

I'm reflecting on an incredible year of growth, accomplishments, and milestones. (re-posting from LinkedIn)

Highlights from my life 2024:

▪️ Academics and Certifications: Completed courses at Dallas College in Intermediate Python Programming, Calculus I and II, Elementary Statistical Methods, Discrete Mathematics, and Python for Data Science. I also earned certifications from Amazon and Google, strengthening my technical skills.

▪️ Professional Development: Attended the Great Minds in STEM (GMiS), US Environmental Protection Agency (EPA) Minority Serving Institutions Symposium, Dallas College & University Startups' Emerging Tech Symposium, and UT Southwestern Medical Center Research & Health Careers conferences, gaining valuable insights and connections in STEM, Artificial Intelligence, and public health.

▪️ Projects and Initiatives: Successfully conducted a Storage Analysis project using Python and Excel, an experience that enhanced my data analysis and problem-solving skills.

▪️ Community and Engagement: Attended many Dallas College STEM League activities and campus tours, connecting with my classmates and navigating STEM. Attended GIS Day at UT Southwestern. I also listened to many guest speakers through STEM League, PyTexas Discord (PyTexas Foundation), and Women in Science and Healthcare (Health Wildcatters), gaining insights and inspiration.

▪️ Personal Milestone: Celebrated one of the most significant events of my life—my wedding in February.

Looking ahead to 2025:
▪️ Completing my Python Developer Certificate.
▪️ Getting accepted into a graduate program in Data Science and AI, with UT Southwestern's Ph.D Health Data Science program as a top choice.
▪️ Improving my health through better habits and consistent effort.
▪️ Being more proactive and cultivating better time management skills.
▪️ Gaining practical experience with Python and Data Science to prepare for future challenges and opportunities.
▪️ Leaving a well-maintained and accessible archival system for my client to support the team's continued success.

As I continue this journey, I’m excited to build on this year’s achievements and push myself to grow personally and professionally.

09/27/2024

Machine Learning (ML) teaches machines to learn from data.

👩‍💻 Traditional Programming: Programmers create rules to process data.

🤖 ML: Algorithms learn rules from data to make predictions & recommendations.