Fastly - Expensive as Hell But Fast as Hell

Fastly went public in 2019 and promptly became the expensive option. They decided to be the fast CDN instead of the cheap CDN. We switched from Cloudflare Pro ($20/month) to Fastly and our bill jumped to $280/month. Same fucking traffic, way more money.

What Makes It Different

150ms Global Cache Purging: When you purge cache, it happens globally in 150 milliseconds. CloudFront takes 10-15 minutes. We learned this the hard way during a pricing bug that cost us like $3K or something while waiting for CloudFront to maybe update. Took 20 fucking minutes and customers were ordering with wrong prices.

70 Big Data Centers vs 300 Tiny Ones: Cloudflare has 300+ locations with tiny edge boxes everywhere. Fastly has about 70 locations with actual hardware that can handle traffic spikes. Better cache hit ratios but you might be 50-100ms further from the nearest server. Trade-off usually works out.

WebAssembly Edge Compute: Runs actual WebAssembly at the edge, not just JavaScript like everyone else. Compile Rust, Go, or C++ and it starts in microseconds. No Lambda cold start bullshit. We moved auth logic to the edge and response times dropped 200ms.

APIs That Work: Configuration changes deploy instantly via their API. No waiting 20 minutes wondering if your distribution updated like with AWS. The API docs are actually readable and examples work on the first try.

The Cost Reality

Our bill went from $80 to like $600 or something when we hit the front page of Reddit. Fun times explaining that shit to finance. Usage-based pricing scales with every byte - $0.12/GB in North America, $0.75 per million requests.

Worth it if you're dealing with shit like:

• E-commerce with dynamic pricing that changes frequently
• News sites with breaking stories every hour
• APIs that need instant cache invalidation
• Applications where 150ms vs 15 minutes actually affects revenue

GitHub, The Guardian, and Shopify use it when cache speed directly affects revenue. They can afford the extra cost.

WordPress blog? Just use Cloudflare's free tier and pocket the difference. Static marketing site? Same deal. Don't overthink it.

Fastly does a few things differently than the usual CDN garbage:

Network Architecture

Fastly has about 70 data centers globally instead of Cloudflare's 300+. Sounds bad but works better - fewer locations with actual hardware instead of tiny edge boxes everywhere. Each location has 100+ Gbps connections and servers that can handle traffic spikes without shitting themselves.

Tradeoff: you might be 50-100ms further from the nearest server compared to Cloudflare. Cache hit ratios are usually better though, so it evens out. We saw 92% cache hits vs 78% on CloudFront.

Instant Cache Purging

When you purge content, Fastly has a dedicated message bus that hits all servers in under 150ms. No "eventually propagate" bullshit. Actually works.

• Cache API responses with short TTLs and purge on data changes
• Handle breaking news without the 15-minute CloudFront wait
• Actually cache user-generated content safely (game-changer for e-commerce)

We cache our product catalog with 30-second TTLs and purge when inventory updates. Lets us serve 10,000 RPS from cache instead of hitting the database.

WebAssembly Edge Compute

Compiles your code to WebAssembly and runs it at edge servers. Startup time is under a millisecond - no Lambda cold start delays. You can deploy:

• A/B testing logic in Rust that modifies responses in real-time
• Authentication middleware that validates JWTs at the edge
• API routing that transforms requests before hitting origin servers

Supports Rust (fastest), JavaScript/TypeScript, Go, Python, and C++. We moved auth logic from Lambda to Fastly and response times dropped 200ms.

Edge storage options: Config Store for configuration data, KV Store for application data, and Secret Store for API keys. All accessible from your edge code with sub-millisecond lookups.

Security Features

The Next-Gen WAF is the old Signal Sciences product that Fastly acquired for $775M. Catches modern attacks like business logic abuse, not just SQL injection from 2005. Starts at $1,500/month for 100M requests.

DDoS protection filters Layer 3/4 attacks before they hit your bill. Layer 7 attacks get rate limited automatically. Built into the CDN service.

Bot detection catches most scrapers but still lets some through. Better than regex hell though. The ML detection learns from traffic patterns across their network.

Real-Time Everything

Log streaming to Elasticsearch, Splunk, S3, or custom endpoints. Logs arrive in seconds, not minutes like other CDNs. Performance metrics update in real-time - cache hit ratios, error rates, geographic distribution.

Dashboard UI looks like it's from 2015 but the data is reliable. Real-time analytics is solid for building custom dashboards. We pipe everything to Grafana for prettier charts.

Fastly is expensive as hell. Their pricing page starts with "$50/month" but that's a $50 credit that disappears faster than your sanity during a production incident.

What You'll Actually Pay

The $50 "Free" Tier: $50 worth of traffic credit per month. That's roughly 400GB of traffic. A decent-sized site will burn through it in a week. Marketing sites last longer, e-commerce sites last days.

Real Usage Pricing: After your credit disappears:

• $0.12 per GB in North America ($0.28-0.34 elsewhere)
• $0.75 per million requests
• Extra charges for Compute, security features, and premium support

Math: A site serving 1TB/month costs $120 just for bandwidth, plus request fees. Factor in requests (usually 2-5M per TB) and you're looking at $150-200/month minimum. Our 2TB/month site costs $280.

Bill Shock Reality

Our bill went from $80 to like $600 or something when we hit the front page of Reddit. Fun times explaining that shit to finance. Unlike Cloudflare's flat Pro plan at $20/month, Fastly scales with every byte. Traffic spikes mean expensive surprises.

Compute Platform Pricing:

• $0.50 per million requests
• $0.000035 per GB-second of memory
• $0.000045 per vCPU-second

First 20ms of CPU time is free. A simple edge function serving 1M requests/month costs about $15-25 including memory and CPU time.

Security Add-ons: Next-Gen WAF starts at $1,500/month for 100M requests. Enterprise pricing for enterprise problems. Small sites just use the built-in DDoS protection that comes free.

When the Cost Makes Sense

Fastly makes financial sense when downtime costs more than CDN bills:

E-commerce Sites: If you're losing $1000/minute during outages, paying $300/month for instant cache purging makes sense. We lost like $5K or something during a 20-minute pricing bug. CDN costs became irrelevant after that shit show.

Media Sites: News sites publishing breaking stories every hour need instant purging. The Guardian switched because ad revenue lost to slow updates cost more than CDN fees.

High-Traffic APIs: APIs serving millions of requests per day benefit from edge compute optimization. Moving auth logic to the edge can save 200ms per request.

The Competition Reality

Cloudflare Pro costs $20/month flat. Fastly costs $200-500/month typically. Enterprise accounts get volume discounts but you need to commit to $10K+ monthly spend for anything meaningful. Most companies don't hit that threshold.

Budget Reality Check

• Small sites (< 1TB/month): Cloudflare is probably fine
• Medium sites (1-10TB/month): Budget $200-500/month for Fastly
• Large sites (10TB+/month): Call sales for enterprise pricing

Hardest part isn't the monthly cost - it's explaining to finance why the CDN bill tripled during a successful product launch. "We made more money but spent more on CDN" is a fun conversation.