Estimated reading time: 10 minutes

Director of Engineering Kent Wills shares how Yelp allocates time upfront for global software engineering modernizations and improvements.

Chores like migrations, patches, or versionings eventually need to be addressed. But really, who has the time? Under a constant barrage of feature requests, development is already underwater, often left without a clear direction or timeline to prioritize critical changes. However, just like house chores, stuff tends to pile up if you put it off.

Kent Wills, director of engineering at Yelp, describes large-scale migrations as “things that are hard to carve out the time for, but everyone knows needs to get done.” An example is keeping Linux versions up-to-date. Another is migrating from Python versions 3.1.x to 3.2.x to leverage new features. While not tied to immediate team goals, these objectives are important to stay competitive, reduce technical debt, and mitigate potential risks.

Ensuring sweeping improvements actually happen really hinges on giving teams the bandwidth. Through effective engineering standards, encouraging paved roads, and strong support from upper management, Wills shares how Yelp is seeing the bigger picture to chip away at the laundry list of engineering to-dos.

Determine what to prioritize

First, you must prioritize what changes matter most. Some migrations are mission-critical. An unsupported package nearing the end of life or a zero-day vulnerability may require immediate action. However, not all changes will be high priorities. For example, Wills shares that a TypeScript migration he worked on was estimated to take four years of developer time to complete. While a desirable improvement, the cost was too challenging to justify.

To assist in engineering planning, Yelp executives determine the streams of work that directly contribute to revenue each year and set prioritization outlines from the top down. In the past two years, leadership has also begun to quantify the value of technical non-revenue-generating projects and the indirect value added from specific engineering modernization efforts, and plan accordingly.

For Yelp, tasks high on the list include Linux migrations, Python migrations, and migrating from batch processing to streaming. Other goals include promoting React as a primary front-end framework, along with standard designs and accessibility features.

Guide prioritizations

Global engineering improvements require guidelines from management – otherwise, everyone will prioritize modernization at their own pace. Without a clear strategy, individual teams “maximize their goals but don’t address risk at the company level,” says Wills. “This can create a really long tail for updates.”

To counteract this, over the last two years, Wills has shepherded what Yelp calls “top technical” initiatives across the company. These guidelines establish best practices and standards ranging from security to efficiency improvements and help to set timelines for change. To help enact standards at the team level, Yelp has elevated certain developers to the role of technical program managers (TPMs), filling a role that was usually done by engineering managers.

In addition to setting timelines in advance, onboarding the right internal evangelists helps migrations tremendously. Wills encourages finding the people with the right mindsets to enact changes. 

Pave a path

Yelp’s Engineering Effectiveness group is a team dedicated to building developer productivity tools and setting company-wide standards. They implement the golden paths (or paved roads) concept, a practice spearheaded by cloud-native companies like Spotify and Netflix. Paved roads use internal developer platforms designed to centralize tools and reduce toil for common workflows, thereby enhancing developer productivity and satisfaction.

At Yelp, these paved paths help align the company around common developer productivity tools. By encouraging everyone to use the same tools, Yelp promotes consistency, which, in turn, elevates organizational standards.

Paved paths aren’t mandated at Yelp, but are highly encouraged due to their cool perks. For instance, React is built into the internal developer platform by default, so developers don’t need to put in extra effort to set it up or manage an alternative. Since paved paths reduce toil and grant usability benefits, they tend to naturally attract developers. “They don’t have to adopt the paved path, but if they don’t, it might be a bumpy road,” he says.

Yelp retains a centralized dashboard to visualize dependency versions and which migrations they need to prioritize. But beyond that, assigning ownership is a key foundational component to leading these initiatives. “Dashboards aren’t good enough,” says Wills. “You need to hold people accountable for the migrations.”

Be prepared

Investing in global initiatives isn’t always easy to justify. “Nothing was crashing or burning by not having this process.” Instead, the benefit is to prevent adverse outcomes and to set the organization up for success in the long term by providing a route for changes.

A fragmented engineering culture, with no clear, uniform plan of attack, can have real consequences. This is especially true when incidents occur where fixes for vulnerable components are difficult to prioritize, let alone discover for many organizations. Surprisingly, two years after the Log4j vulnerability (the infamous remote code execution vulnerability in Apache log4j) was discovered in late 2021, two of five applications were still running vulnerable versions.  If an engineering culture is fragmented, it is less equipped to respond to such sudden threats.

The beauty is that, by focusing on engineering effectiveness, Yelp was well-equipped to respond when Log4j arose. “We already had that infrastructure in place,” says Wills. “We knew immediately which systems were affected and could immediately assign this to teams.”

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Get it done

All in all, while modernization is tricky to mandate, it’s necessary to prioritize important changes. A top-down approach is required here because, stuck in the day-to-day development, it’s tough to see the forest from the trees.

“It’s very hard at the team level to understand this,” says Wills. So, by setting clear, annual plans for things like end-of-life updates or language migrations, you clarify focus. Shared dashboards and paved paths can further grant better visibility across the organization’s software portfolio and provide smoother methods for updates.

Big engineering to-dos might not feel urgent today, but ignoring them risks turning minor messes into full-blown disasters. By assigning ownership, breaking down the work, and making the path to completion as smooth as possible, you can get the engineering to-dos checked off before it starts overflowing.