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Let’s say we have a table with an <code>id</code> and <code>name</code> fields. The table holds over 100 million rows and we want to sample a random row in the table without throttling the database.

Write a query to randomly sample a row from this table.

Input:

<code>big_table</code> table

<table>
<thead>
<tr>
<th>Columns</th>
<th>Type</th>
</tr>
</thead>

<tbody>
<tr>
<td><code>id</code></td>
<td>INTEGER</td>
</tr>

<tr>
<td><code>name</code></td>
<td>VARCHAR</td>
</tr>
</tbody>
</table>

Write a query to randomly sample a row from a big table.

Random SQL Sample

Let’s say that your company is running a standard control and variant AB test on a feature to increase conversion rates on the landing page. The PM checks the results and finds a .04 p-value.

How would you assess the validity of the result?

Experiment Validity

Let’s say you work for a social media company that has just done a launch in a new city. Looking at weekly metrics, you see a slow decrease in the average number of comments per user from January to March in this city.

The company has been consistently growing new users in the city from January to March.

What are some reasons why the average number of comments per user would be decreasing and what metrics would you look into?

What metric could be used to measure if active users are still engaging on the platform despite an overall decrease in the average number of comments per user?

What metric could be used to measure if active users are still engaging on the platform despite an overall decrease in the average number of comments per user?

Decreasing Comments

How would you investigate a decline in the average number of comments per user?

Fastly Salaries by Position

Fastly helps people stay better connected with the things they love. Fastly's edge cloud platform enables customers to create great digital experiences quickly, securely, and reliably by processing, serving, and securing our customers' applications as close to their end-users as possible - at the edge of the Internet. The platform is designed to take advantage of the modern internet, to be programmable, and to support agile software development. Fastly's customers include many of the world's most prominent companies, including Vimeo, Pinterest, The New York Times, and GitHub. We're building a more trustworthy Internet. Come join us. Senior Software Engineer, Data Services Posting Open Date: Oct. 1, 2024 Anticipated Posting Close Date*: Oct. 30, 2024 *Job posting may close early due to the volume of applicants. Senior Software Engineer - Data Services The Data Services team is responsible for developing, supporting, and operating the software, systems & infrastructure that Fastly's products are built on top of. We are looking for a Senior engineer who is interested in the space at the intersection of security & data to join the team. As a Senior Software Engineer, you will be responsible for leading project implementations, collaborating with others, and growing/adapting systems to the needs of the business. What you'll do: <ul><li>Develop and maintain the software and systems that ingest, manage, and process the data that powers Fastly's products</li><li>Partner with others in both the local team and across Fastly to deliver larger, cross-team projects on time </li><li>Scale out large data systems to meet the growing needs of Fastly and it's customers</li><li>Use infrastructure as code and configuration management systems to run the software you develop </li><li>Build in anticipation of the reliability, scalability, and performance needs of our systems </li><li>Create and maintain dashboards and alerts to monitor our services</li><li>Participate in the on-call & support rotation we share</li><li>Help to establish the practice of using SLOs to guide decisions and priorities</li></ul> What We're Looking For: <ul><li>At least 5 years of professional experiencing developing software in a distributed environment</li><li>Significant experience programming in Go and Kotlin </li><li>Understanding of the challenges involved in operating and evolving scalable and reliable data storage systems of multiple types</li><li>A thoughtful and empathetic approach to design and implementation</li><li>Experience with message queues such as Google Pub/Sub, NSQ, Kafka, Kinesis</li><li>Experience with container technology, Kubernetes/Docker/Helm, or similar</li><li>Experience with metric collection and monitoring tools like Prometheus or services like DataDog</li><li>Eagerness & aptitude to learn new languages & technologies</li></ul> We'll be super impressed if you have experience in any of these: <ul><li>Experience with Fastly's products and services</li><li>Experience working with infrastructure as code like Terraform, Chef, Ansible, Puppet</li><li>Knowledge of one or more relational and non-relational storage systems (MongoDB, MySQL, BigQuery, BigTable, etc.)</li><li>Experience with Elasticsearch and Kibana</li></ul> Work Hours: <ul><li>This position will require you to be available during core business hours as well as occasional nights and weekends as required for the on-call rotation.</li></ul> Work Location(s) & Travel Requirements: This position is open to both hybrid and remote work locations in the US. The preferred hybrid locations for this position are: <ul><li>Denver, CO</li><li>New York, NY</li></ul> Fastly currently embraces a largely hybrid model for most roles which allows employees flexibility to split their time between the office and home. We are willing to consider remote candidates in the United States only. Pursuant to the San Francisco Fair Chance Ordinance and the Los Angeles Fair Chance Initiative for Hiring Ordinance, we will consider for employment qualified applicants with arrest and conviction records. Salary The estimated salary range for this position is $167,790 to $209,740. Starting salary may vary based on permissible, non-discriminatory factors such as experience, skills, qualifications, and location. This role may be eligible to participate in Fastly's equity and discretionary bonus programs. Benefits We care about you. Fastly works hard to create a positive environment for our employees, and we think your life outside of work is important too. We support our teams with great benefits that start on the first day of your employment with Fastly. Curious about our offerings? We offer a comprehensive benefits package including medical, dental, and vision insurance. Family planning, mental health support along with Employee Assistance Program, Insurance (Life, Disability, and Accident), a non-accrual vacation policy and up to 18 days of accrued paid sick leave are there to help support our employees. We also offer 401(k) (including company match) and an Employee Stock Purchase Program. For 2024, we offer 10 paid local holidays, 11 paid company wellness days. Why Fastly? <ul><li>We have a huge impact. Fastly is a small company with a big reach. Not only do our customers have a tremendous user base, but we also support a growing number of open source projects and initiatives. Outside of code, employees are encouraged to share causes close to their heart with others so we can help lend a supportive hand.</li><li>We love distributed teams. Fastly's home-base is in San Francisco, but we have multiple offices and employees sprinkled around the globe. As a new hire, you will be able to attend our IN-PERSON new hire orientation in our San Francisco office! It is an exciting week-long experience that we offer to new employees to build connections with colleagues across Fastly, participate in hands-on learning opportunities, and immerse yourself in our culture firsthand.</li><li>We value diversity. Growing and maintaining our inclusive and diverse team matters to us. We are committed to being a company where our employees feel comfortable bringing their authentic selves to work and have the ability to be successfulevery day.</li><li>We are passionate. Fastly is chock full of passionate people and we're not 'one size fits all'. Fastly employs authors, pilots, skiers, parents (of humans and animals), makeup geeks, coffee connoisseurs, and more. We love employees for who they are and what they are passionate about.</li></ul> We're always looking for humble, sharp, and creative folks to join the Fastly team. If you think you might be a fit please apply! A fully completed application and resume or CV are required when applying. Fastly is committed to ensuring equal employment opportunity and to providing employees with a safe and welcoming work environment free of discrimination and harassment. Our employment decisions are based on business needs, job requirements and individual qualifications. All qualified applicants will receive consideration for employment without regard to age, ancestry, color, family or medical care leave, gender identity or expression, genetic information, marital status, medical condition, national origin, family or parental status, physical or mental disability, political affiliation, protected veteran status, race, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable laws, regulations and ordinances. Consistent with the Americans with Disabilities Act (ADA) and federal or state disability laws, Fastly will provide reasonable accommodations for applicants and employees with disabilities. If reasonable accommodation is needed to participate in the job application or interview process, to perform essential job functions, and/or to receive other benefits and privileges of employment, please contact your Recruiter, or the Fastly Employee Relations team at candidateaccommodations@fastly.com or 501-287-4901. Fastly collects and processes personal data submitted by job applicants in accordance with our Privacy Policy. Please see our privacy notice for job applicants.

Fastly Interview Questions

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Fastly Interview Questions

Fastly Salaries by Position

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