Build vs Buy: Why FlashDocs Beats Building a Slide Generation Tool from Scratch

If you're a developer or tech lead considering automating slide creation, you're probably asking yourself: should we build it or buy it?

On one side: DIY with open-source libraries, scripting workarounds, or hacking the Google Slides and PowerPoint APIs. On the other: plug into FlashDocs and be done in minutes.

Here’s why we think “buy” wins — especially when the “buy” is a purpose-built, API-first service that handles all the gnarly details for you.

What We’ll Cover

• The hard parts of building slide automation from scratch
• Google Slides & PowerPoint API pain points
• The cost of maintaining your own generator
• How FlashDocs simplifies it all with one API
• Example: 5 lines with FlashDocs vs 500+ lines of custom code
• When it might make sense to build (and why most teams don’t)

What Makes Slide Generation Hard?

On the surface, generating slides feels like something a few scripts could handle. But here’s what you’re really signing up for:

• Parsing and editing PPTX files (which are XML inside zip archives)
• Working with COM-based PowerPoint automation (read: Windows-only, flaky, and ancient)
• Dealing with Google Slides API quotas, batching, and slide indexing logic
• Handling layout and formatting for text, images, and charts
• Managing versioning when either API changes (which they do, often)

It’s not that it’s impossible — it’s just a lot of complexity for something that should be simple.

Google Slides API Is Not Your Friend

Developers often try the Google Slides API first. It’s well-documented and relatively modern, but:

• You have to know the slide and element indexes
• There’s no easy Markdown support
• Images require Google Drive links and permissions
• Batching requests correctly is tedious
• No native support for themes, branding, or templates

You can make it work, but it’s like writing React apps in vanilla JS — doable, but why?

PowerPoint Automation: A Legacy Mess

On the PowerPoint side, you’ll be dealing with one of two paths:

1. Scripting PowerPoint using Office Interop (only works on Windows, requires Office installed)
2. Writing XML directly into .pptx files (brittle, undocumented, easy to break)

Even with libraries like python-pptx or pptxgenjs, you’ll quickly hit limitations when you want to:

• Use real design templates
• Insert dynamic content in charts or tables
• Support images with crop/fill/layout rules
• Generate both PowerPoint and Google Slides with one system

FlashDocs Makes It Simple

FlashDocs abstracts all of this behind a clean, modern API. You:

• Upload or reference a template (PowerPoint or Google Slides)
• Add merge tags like [client_name] or [logo_url]
• POST your data to our API
• Get a polished, brand-safe slide deck back

It handles:

• File formatting
• Template enforcement
• Markdown conversion
• Image placement and styling
• Cross-platform output

You just provide the content. FlashDocs takes care of the rest.

Real Example: FlashDocs vs DIY

With FlashDocs:

curl --request POST \
 --url https://api.flashdocs.ai/v3/generate/deck \
 --header 'Authorization: Bearer $API_KEY' \
 --header 'Content-Type: application/json' \
 --data '{
   "presentation_name": "Q3 Overview",
   "template_id": "team-deck",
   "text_placeholder_manual_insertions": [
     { "placeholder": "[team_name]", "value": "Data Infra Team", "slide_index": 1 }
   ]
 }'

With DIY PowerPoint XML + Google Slides API:

• 500+ lines of code across multiple files
• Manual layout and styling logic
• Constant debugging of element references and slide indexes
• Ongoing maintenance with each Office/Slides update

We’ve done it both ways. FlashDocs wins every time.

Cost of Building = More Than You Think

Here’s what you’ll likely spend building your own system:

• 4–8 weeks of engineering time
• DevOps overhead for hosting/generating files
• QA and regression testing when APIs change
• Brand team frustrations when templates break

Even modest hourly rates will push the total into five figures fast. And that doesn’t include long-term maintenance.

Bonus Features You’d Have to Build Yourself

FlashDocs gives you powerful extras out of the box:

• Markdown → Slides conversion
• Dynamic charts and tables
• Conditional logic (e.g. hide slide if value is empty)
• Asset hosting for logos/images
• Support for both Google Slides and PowerPoint

Good luck building all that in-house.

When You Might Build (and Still Use FlashDocs Later)

There are times when rolling your own makes sense:

• You only need to generate one very specific format
• You already have deep XML/PPTX expertise in-house
• You’re building a throwaway tool for a short-term task

Even then, many teams prototype something, realize how painful it is, and end up switching to FlashDocs anyway.

Final Thoughts: Build Smarter, Not Slower

You could spend weeks building a fragile, limited version of what FlashDocs does — or you could start generating professional-grade decks today with a few API calls.

Your team’s time is better spent on your product, not reinventing presentation tooling.

🚀 Start building or try the demo and skip the PowerPoint XML rabbit hole.

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