Rust Foundation website seamlessly scales to meet 2-3x increase in demand with Fastly

The challenge

The number of Rust developers nearly tripled between 2021 and 2023, reaching 2.8 million in 2023. Its usage is expected to keep growing following the White House Office of the National Cyber Director (ONCD) recommendation that software development organizations begin to use memory-safe languages such as Rust for applications and systems development.

For the Rust Foundation, Rust’s popularity translates to dramatic growth in traffic on its website. Much of the traffic comes from downloading crates, the packages developers download to write applications. In 2021, traffic averaged 0.5 petabytes (PB) per month. By mid-2024, that number increased to 2.5 PB monthly;  the organization expects to see as much as 4-5 PB monthly in 2025.

The foundation had relied on AWS, as an in-kind donation, for its infrastructure. But as its bandwidth needs continued to grow, the Rust Foundation faced a difficult choice: ask for more AWS credits, find another in-kind provider, or pay for bandwidth out of pocket, which would get expensive fast.

The solution 

Fastly has long been a supporter of Rust. We use it extensively in our own technologies, so in 2023 Fastly invited the Rust Foundation to join the Fast Forward initiative, a program that offers free services to open source projects and the nonprofits that support them. Fast Forward focuses on building community among the building and maintenance of an internet that is faster, safer, and more inclusive—exactly what the Rust Foundation does.

"We immediately jumped on the opportunity to have a reliable partner in Fastly," said Joel Marcey, Director of Technology at the Rust Foundation. "Getting Fastly onboarded to our processes and pipelines was very smooth, and Fastly support was extremely responsive."

The Rust Foundation began utilizing Fastly’s CDN to serve Rust’s releases and crates to users worldwide. Whenever someone installs Rust or adds a dependency to their project, the necessary artifacts are downloaded seamlessly from Fastly.

For the releases, the foundation was able to set up a CDN service very quickly, which has been working flawlessly ever since. The configuration is simple and easy to maintain, as they can rely heavily on the sensible defaults provided for VCL services.

When it came to crates, the Rust Foundation opted to use Fastly Compute, enabling developers of crates.io, who are already proficient in Rust, to more easily maintain the CDN service themselves. It allowed the infrastructure team to delegate control over a critical service to developers, knowing that Rust’s strong tooling would help them write robust, safe, and reliable code that could confidently run at the edge. This strategy made it easier and quicker for the team to implement changes and reduced the workload on the infrastructure team since they only needed to review changes.

Since adopting Fastly, the Rust Foundation has rapidly shifted more and more traffic to Fastly's CDN. Fastly is now the primary CDN for all Rust assets, with 80% of the foundation's traffic now moving through Fastly. 

Scaling traffic while improving performance

The increased interest in Rust is exciting, but scaling internet services often raises concerns about performance. The Rust Foundation has met rapid scaling demands without issue since adding Fastly to the stack. "As we scale, Fastly has been right there with us," Marcey said. In a six-month period, its website increased by 0.5 PB of bandwidth per week, with no downtime, no performance degradation, and no issues. "If anything, since adopting Fastly we've seen an improvement in how things are being delivered to the Rust community. Our infrastructure engineers have nothing but good things to say about the addition of Fastly," said Marcey.

Gaining visibility to prevent deterioration of service

Marcey also named Fastly's visualization platform as a key benefit for the Rust Foundation. "We're very easily able to get the metrics to show people how much bandwidth we've used this week," Marcey said. As traffic levels continue to increase, the Rust Foundation can get insights into network performance and user behavior to ensure that potential problems are identified before services are disrupted.

Preserving resources to support the community

One of the biggest benefits the Rust Foundation gets from using Fastly is having more time and money to put towards initiatives and programs that support the Rust community. "It's hard to overstate how valuable Fastly has been to the Rust Foundation," said Marcey. "It's important that we put our money where it should be going. If we spend it on infrastructure, there won't be much left to accomplish all the other things we want to do."

Key takeaway

Adding Fastly's CDN to its infrastructure gave the Rust Foundation the scale and the visibility it needed to keep up with the soaring demand for Rust assets. "Between Fastly providing us efficient bandwidth and its support of Rust as a first-class language, we are able to continue to provide Rust maintainers, developers, and users a continued high-level experience. This may be one of the reasons why Rust continues to be one of the most loved languages," said Marcey.