Three candidates describe Photon's Java-focused engineering interviews: Spring Boot microservices, Stream API and functional programming, coding tasks, and HR calls. Their reports differ on organization and follow-up.
$90K
Avg. Base Comp
$120K
Avg. Total Comp
3-4 rounds
Typical Rounds
Not reported
Process Length
Candidates describing Photon engineering interviews mention Java backend fundamentals more than anything else. The three reports cover a Backend Developer, an Android Lead and a Java Full Stack Developer, so read them as adjacent software engineering experiences rather than one fixed loop.
The most detailed technical account comes from the Android Lead candidate, who reports a first round that asked for two Spring Boot microservices, a product service and an order service. The task covered basic CRUD endpoints and API calls between the services. The second technical round reportedly moved to Stream API features and functional programming problems in Java. That candidate also had two HR conversations and received a conditional offer pending a client round.
The Java Full Stack candidate reports two technical rounds plus a project coding round. Questions included Java basics, functional interfaces, stream coding, design patterns, easy DSA and multithreading concepts. That candidate got no offer and describes a long silence after the interviews.
The Backend Developer candidate reports a few general technical questions and one coding task, and describes the process as disorganized. The coding task ran on an external site rather than in the IDE they were told to prepare. They say the interviewer could not clarify questions. They did not get an offer.
Practice building small REST services with clear inter-service calls, and rehearse Java streams and functional interfaces. Ask clarifying questions early, and confirm next steps and timelines in writing.
Synthesized from 3 candidate reports by our editorial team.
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Real interview reports from people who went through the Photon process.
I went through four rounds at Photon—two technical interviews and two HR conversations—and made it all the way through to offer discussions. The process felt thorough but intense. The first technical round focused on backend development, and I was asked to design two microservices: a product service and an order service in Java Spring Boot. The task involved implementing basic CRUD operations—getting all products, fetching a product by ID, retrieving orders, and getting a specific order—with API interactions between the two services to demonstrate how they'd communicate. It was a realistic scenario that tested both my ability to structure services and understand inter-service communication. The second technical round went deeper into core concepts. I fielded questions on Stream API and its features, then tackled coding problems that tested my grasp of functional programming patterns in Java. The interviewer was patient and created a comfortable environment, asking thoughtful questions that moved between conceptual understanding and actual implementation. Beyond the technical rounds, I had two HR calls covering my background, career goals, and fit with the team. Throughout these conversations, various HR representatives engaged with me, and we moved into salary discussions fairly late in the process. The whole thing was demanding—they really did ask a lot of questions across both rounds—but I felt like I had a genuine shot. At the end, I received a conditional offer pending a client round, which felt like real progress. That said, I'd encourage other candidates to stay on top of communication timelines and have clarity on next steps in writing, because delays can happen.
Prep tip from this candidate
Brush up on Java Spring Boot microservices design before your interview—specifically, how to structure service APIs and handle inter-service communication. Also be ready to discuss Stream API features and functional programming patterns in depth, as those concepts came up prominently.
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Sourced from candidate reports and verified by our team.
Topics based on recent interview experiences.
Featured question at Photon
Select the 2nd highest salary in the engineering department
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Synthesized from candidate reports. Individual experiences may vary.
One candidate reports a first technical round that asked for two Java Spring Boot microservices, a product service and an order service. The task involved CRUD endpoints and API interaction between them. Expect to show how you structure services and how they communicate.
Candidates report core Java questions in a second technical round. One describes Stream API features and functional programming problems. Another describes Java basics, functional interfaces, stream coding, design patterns, easy DSA and multithreading concepts. Interviewer depth reportedly varies, so be ready to clarify questions yourself.
One candidate reports a separate project coding round after two technical rounds. Another reports a single coding task on an external website, even though they were told to have an IDE ready. Confirm the platform and expectations beforehand, since the format may differ between interviews.
One candidate reports two HR conversations covering background, career goals and team fit, with salary discussed fairly late. That candidate received a conditional offer pending a client round. Another reports about four weeks of silence after finishing the rounds, so ask HR for a feedback timeline and keep written records.
