This article is meant to expand on this open visual map I assembled over the last few months.

Intro

Are you excited about AI? Ready to build something amazing? A product or a business? You're not alone!

The world of AI is exploding with possibilities. There are tools, platforms, frameworks, and resources everywhere you look - maybe even too many to sort through on your own. That's where this guide comes in.

We'll walk through each step of the ML development cycle together. You'll discover what matters, when it matters, and why. Some steps blur into each other, and certain platforms serve multiple purposes. That's okay. Skim through what interests you most, and dive deeper when something catches your eye.

Speedrunning? Focus on getting from raw idea to happy customer. Everything in between is just details we can optimize along the way.

The Foundation

Starting out? You might fixate on models and deployment. That's natural. But there's more to the story.

This article has been published on HackerNews too. Any votes/comments are welcome.

As you move beyond those first prototypes, you'll discover that building AI products involves a deeper journey. Let me show you why each step matters:

- Data Quality Issues: Poor data in means poor results out. When your initial data curation falls short, you'll face endless cycles of expensive re-training and cleanup.

- Technical Debt: Rush to deploy now, pay the price later. Without proper infrastructure and monitoring, you're building on quicksand. Each shortcut becomes a future roadblock.

- Resource Waste: Teams without a plan burn through resources like wildfire. They train models they don't need. They over-provision infrastructure they barely use. Money vanishes into the digital void.

- Maintenance Nightmares: Documentation matters. Monitoring matters. Skip these fundamentals, and you'll find yourself unable to maintain or improve your models. Your future self will not thank you.

- Scalability Barriers: Ad-hoc solutions create bottlenecks. These barriers become walls. Walls that prevent your AI solutions from growing with your success.

Following a structured development cycle changes everything. It helps teams see around corners. It keeps resources flowing to the right places. Most importantly, it builds AI solutions that last - solutions that deliver real business value, day after day.

Let's walk through each step of this lifecycle together. In a systematic manner.

1. Data Acquisition and Curation

It all starts with data. Raw. Messy. Full of potential.

Your data might come from anywhere. Public datasets wait on Kaggle. Governments share treasure troves of information. Research institutions open their archives. Or maybe it's your own data, living in warehouses, CRMs, and countless spreadsheets. Need something specific? Third-party providers stitch together custom solutions - for a price.

But raw data isn't enough. It needs care. Attention. Purpose.

You'll clean it first - removing duplicates, handling missing values, smoothing out the rough edges. Then comes curation. Adding context. Labels. Metadata. It's complex work, but specialized tools make it manageable.

Let's look at an example. Here's raw data, exported from a legacy system:

Now see it transformed - structured, labeled, ready for action:

Privacy matters here. Compliance isn't optional. GDPR, CCPA, HIPAA - they're not just acronyms. They're promises to protect. If your data warehouse handles these well, you're ahead of the game.

2. The Foundation: Models

Let's assume you're familiar with what an AI/ML model is. Your first big decision? The classic "buy vs. build" question.

Think about this. Some models are trained on 25,000 GPUs. They learn from billions of data points. They cost millions to create. You could use one of those. Or you could build your own from scratch. Each path leads somewhere different.

Let's make it crystal clear:

- Buying means using someone else's model

- Building means training your own

Concrete example. Say you're working with human language. You need to understand words, sentences, grammar. The smart move? Grab an open-source model like Llama 3 or Mistral. They've done the heavy lifting.

But maybe your company is different. Maybe you've got unique data about Earth's climate that no one else has. Petabytes of satellite imagery. Years of temperature readings. That's when you might want to train your own model, just like IBM and NASA did.

Consider the climate impact. The equivalent of five cars' lifetime emissions is no small footprint.

Here's a framework to help you weigh these trade-offs:

Benefits	Costs
Off the shelf models: - Faster time to market - No infrastructure headaches - Battle-tested reliability - Rich documentation and examples - Risk reduction - experts did the heavy lifting In-house models: - Your data stays yours - Perfect fit for your domain - Complete quality control; identify and correct biases early - Edge cases? Handled - Long-term cost efficiency - no API fees, no vendor lock-in	Off the shelf models: - API fees add up. Fast - Vendor lock-in is real; you're dependent on the provider for support, updates and troubleshooting; - Quality monitoring never stops - Hidden biases lurk in pre-trained data In-house models: - Infrastructure isn't cheap (GPUs, TPUs, etc.) - Talent costs more: ML engineers, data scientists, compliance teams - Development never ends - Operations overhead grows with scale

Benefits

Costs

Off the shelf models:

- Faster time to market

- No infrastructure headaches

- Battle-tested reliability

- Rich documentation and examples

- Risk reduction - experts did the heavy lifting

In-house models:

- Your data stays yours

- Perfect fit for your domain

- Complete quality control; identify and correct biases early

- Edge cases? Handled

- Long-term cost efficiency - no API fees, no vendor lock-in

Off the shelf models:

- API fees add up. Fast

- Vendor lock-in is real; you're dependent on the provider for support, updates and troubleshooting;

- Quality monitoring never stops

- Hidden biases lurk in pre-trained data

In-house models:

- Infrastructure isn't cheap (GPUs, TPUs, etc.)

- Talent costs more: ML engineers, data scientists, compliance teams

- Development never ends

- Operations overhead grows with scale

The buy vs. build decision isn't final.

Your choice can evolve. Many start with pre-trained models, then build in-house capabilities as they grow. It's a journey, not a destination. Hybrid approaches are common.

Let's see this framework in action with a few examples:

1. Customer Service Automation

- Buy: OpenAI's API handles queries. Your prompts shape the voice

- Build: Your data trains your model. Your rules. Your way

- Key factor: How much proprietary support data do you have?

2. Document Processing

- Buy: Pre-trained OCR and NLP do the heavy lifting

- Build: Custom models speak your document's language. They are fit for your types of documents.

- Key factor: How unique are your documents?

3. Product Recommendations

- Buy: Generic algorithms point the way

- Build: Your user data creates magic. Your models are tailored to your users' preferences.

- Key factor: Is your user behavior data unique enough to matter?

3. Fine-tuning for Success

Whether you "buy or build", fine-tuning matters. It refines models to fit your needs as they evolve. This process is efficient, with a smaller dataset. It saves time and resources. But be cautious. Limited data can lead to overfitting - a dead end for models.

Fine-tuning means continuous improvement.

Think of training as teaching a child from birth. It's slow. Demanding. Resource-hungry. The model learns to spot patterns in data, testing its knowledge against validation sets. Fine-tuning? That's more like teaching new tricks to an expert. You're building on existing knowledge. Adapting. Refining.

Watch out. The pitfalls are subtle:

- It's still slow

- It still needs serious compute power

- Too little data? You'll underfit

- Too much focus? You'll overfit

- Balance is everything

There's a hidden danger: catastrophic forgetting. Your model might excel at new tasks but forget its original skills. Symptoms? Loss of performance on tasks the model was initially good at. Like a musician who masters jazz but can no longer play classical.

One more thing: guard against data-leakage. Keep your training and validation sets separate. Clean. Distinct. Your model's future depends on it.

4. Model Hosting Infrastructure

A trained model is simple, really. Just weights and biases. Numbers in a file. That's all.

The format? It varies. You might see .safetensors. Or .bin. Maybe .h5 or .pt. Each serves its purpose.

Working with teams? You'll need somewhere to host these files. Somewhere that handles versions. Hugging Face shines here. Git works too, though it needs some setup. Those large files can be tricky.

Data engineers know this dance. DevOps teams too. Hosting isn't new - we've been doing it for years. But AI brings its own twists:

1. Model serving infrastructure

2. Version control with A/B testing

3. GPUs, GPUs, GPUs

Think security. Think access control. These models can hold secrets - treat them like your company's crown jewels. Like that critical internal database you guard so well.

5. Showcasing Your Models

This step has the smallest footprint. Yet it can feel the most rewarding.

Working on open-source or research models? You'll want to give others a chance to play. Who doesn't like testing a good AI?

Streamlit and Gradio make this simple. They handle the hard parts - all those client-server interactions you'd rather not think about. They're true full-stack solutions. All your UI elements live in a few files. Sometimes just one.

Platforms like Hugging Face shine here. They've sparked a new trend of "AI apps". Host your model on their platform. Build your UI on top. Watch the magic happen.

6. Production Deployment

So your model is ready for prime time. Your users are eager to try it out. Exciting times!

How will it integrate with your product? Through inference endpoints, usually. REST APIs or real-time websockets. They take inputs. Process them. Return results.

For LLMs, it's different. SDKs handle the heavy lifting. They abstract away the complexity. Make it simple.

REST APIs? They're everywhere in AI. Most providers follow similar patterns. Especially for chat interfaces. Makes switching providers easier.

Models need maintenance, like any system. Updates. Retraining. Replacement. That's where MLOps shines. CI/CD pipelines automate the process. Keep deployments consistent. Make updates smooth.

Watch your resources in production. Inference isn't cheap. It's not like simple CRUD operations. Your hardware needs will vary. GPUs are a common requirement. Small models might run on CPUs. Image generation? That needs GPU power. Lots of it.

7. Monitoring and Maintenance

Once your model is in production, you'll want to keep an eye on it. Like any system, it will have its quirks. Its edge cases. Its moments of brilliance and confusion.

While monitoring might feel familiar to DevOps teams, ML ops brings its own challenges. Its own metrics to watch. Its own patterns to understand.

Here's what you'll need to track:

1. Accuracy - is it still getting things right?

2. Latency - how fast does it respond?

3. Throughput - how many requests can it handle?

4. Cost - are resources being used efficiently?

5. Model drift - is it losing touch with reality?

6. Error rates - where does it stumble?

7. Confidence scores - does it know when it's unsure?

When your model sits in a critical path, monitoring can't wait. Real-time alerts matter. Budgets need watching. Thresholds need setting.

For example: Watch how your model performs on real-world data over time. Set alerts for sudden accuracy drops. Don't ignore those gradual declines. They'll sneak up on you.

Closing

Remember, you don't have to tackle everything at once. Each step in the ML lifecycle can be handled by different teams. Different expertise levels. It's modular.

I've started maintaining a curated list of helpful tools and resources. It's open-source. Growing. Living. Feel free to check it out and contribute if you'd like!

Did you find this guide helpful? Share it with others who might benefit. The future of AI and ML is whatever we make of it.

Let's make it amazing.

P.S. Thanks to Breno for reviewing this post and for invaluable feedback.

Beyond the Hype: Your Complete Guide to ML Development