As a Software Engineer at P99soft, you are at the intersection of enterprise platform architecture and high-impact client solutions. You are not just writing code; you are building the connective tissue for complex business ecosystems, specifically within the NetSuite and Salesforce domains. Your work directly influences how organizations manage their CRM and ERP operations, requiring a balance of technical precision and business logic understanding. This role is critical to P99soft because it demands both depth in core programming and the agility to adapt to specific platform requirements. You will be expected to solve high-stakes integration challenges and optimize platform performance, making your contribution highly visible to both internal leadership and external clients. Whether you are debugging a complex SOQL query or architecting a REST API integration, your technical output serves as the backbone for the company’s service delivery.
High-Level Technical Screening
reportedInitial assessment to evaluate basic technical skills and fit.
What to demonstrate
- Initial assessment to evaluate basic technical skills and fit
- Depth in Java
How to prepare
- Answer aloud and timed: Can you explain the core pillars of OOP and how you apply them in your daily work?
- Answer aloud and timed: What is the difference between specific Java keywords (e.g., static vs. final)?
Deep-Dive Assessments
reportedIn-depth evaluations focusing on specific technical competencies.
What to demonstrate
- In-depth evaluations focusing on specific technical competencies
- Depth in Java
How to prepare
- Answer aloud and timed: Describe the structure of a class and how you determine method visibility.
- Answer aloud and timed: How do you manage memory and performance in your applications?
Conversation with Leadership
reportedFinal discussion with leadership to assess cultural fit and alignment.
What to demonstrate
- Final discussion with leadership to assess cultural fit and alignment
- Depth in Java
How to prepare
- Answer aloud and timed: How do you construct and optimize SOQL queries for large datasets?
- Answer aloud and timed: Describe your experience building and securing REST API integrations.
PracHub editorial advice for the preparation topics above.
Master the Basics
Many candidates fail because they focus on complex algorithms while neglecting the fundamentals of OOP and Java keywords.
Communicate Your Process
During coding rounds, think out loud. We want to see how you troubleshoot and refine your logic in real-time.
Research the Platforms
If applying for the Salesforce or NetSuite tracks, spend time reviewing the official documentation for those platforms.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
How do you manage memory and performance in your applications?
How do you manage memory and performance in your applications?
Approach
- Say what the runtime actually does before reasoning about the code.
- Name what is shared across threads and what owns each piece of state.
- Identify the window where an invariant is briefly untrue.
- Distinguish a value from a reference to it, and say which one you handed out.
Follow-up
- What happens if two callers reach this at the same time?
- Where could this allocate more than you expect?
Diff a projection against the primary without per-row point reads
The listing projection has drifted and some rows show a stale version. The primary holds 40,000,000 resource rows across 12,000 tenants while serving 1,200 writes and 14,000 reads per second. The obvious repair, reading each resource row and comparing its version against the projection, is correct and would eventually finish. Explain precisely why it is unacceptable here, then give a diff that finds the differing rows, state its complexity, and make it safe to run against a live primary. Replication lag is usually under 100 ms and is not bounded.
Approach
- Quantify the naive cost rather than calling it slow: 40,000,000 point reads at even 0.5 ms each is over five hours serialised, and the only lever is concurrency, which is exactly what you cannot spend. The primary's pool is sized for the write path, and 40,000,000 random reads evict the buffer cache that sustains the 85 percent cache hit rate, so the audit degrades the system it is auditing.
- Replace random access with one ordered pass per side. Both sides can be read in (tenant_id, resource_id) order, which is a sequential scan on each and a merge join in O(n) time and O(1) memory. For a dense diff that is the whole answer, and it reads the primary once instead of 40,000,000 times.
- For the expected sparse case, compare range hashes instead of rows: partition the key space, compute per range an order-independent aggregate over hash(resource_id, version), compare aggregates, and descend only into ranges that differ. With d differing rows and branching factor B, at most d ranges mismatch per level, so the drill-down examines O(d log_B(n/d)) ranges and reads full rows only in mismatching leaves.
- Aggregate with a sum modulo 2^64 or a multiset hash, never XOR. XOR is order-independent but self-cancelling, so two rows wrong in the same way, or a row duplicated on one side, leave the range aggregate matching and the range is declared clean.
Follow-up
- The diff reports 900 stale rows. How do you decide between patching those rows and rebuilding the projection from resource_revision?
- Same job, but the projection lives in a search index that cannot be scanned in key order. What changes?
Merge partitioned event streams into one ordered feed with bounded lateness
The read-model service consumes 64 log partitions carrying about 4,000 events per second in total. Each partition is ordered within itself, but partitions drift by up to 30 seconds, and the activity feed must present a tenant's events in occurred_at order. Produce the merge. State its complexity, the buffer it requires in events and in bytes, what happens when one partition is idle, and what you do with an event that arrives after you have already emitted its position. Payloads average 1 KB.
Approach
- Merge with a min-heap over the 64 partition heads keyed on (occurred_at, event_id): O(log P) per event and O(n log P) overall. The tie-break on event_id is what makes the output deterministic when two partitions carry the same millisecond, which matters because the feed is paginated and a non-deterministic order reorders pages under the reader.
- Emitting the heap head is only correct once every partition has produced everything up to that timestamp, so the emit condition is a watermark: the minimum across partitions of the highest occurred_at seen, less the allowed lateness. Events are held until the watermark passes them, which is what turns individually ordered streams into a jointly ordered one.
- Size the buffer from the lateness rather than guessing: 4,000 events per second times 30 seconds is 120,000 buffered events, and at 1 KB each about 120 MB of heap. That number is the real price of the ordering guarantee and belongs in front of whoever asked for it.
- Handle the idle partition explicitly, because it fails the feed rather than corrupting it: a partition with no traffic never advances its own maximum, so the watermark freezes and output stops entirely. Either every partition emits a periodic idle marker carrying the broker's current time, or the watermark falls back to wall clock for a partition silent beyond a threshold.
Follow-up
- The lateness budget is raised to five minutes. What is the new buffer, and what besides memory changes?
- The consumer restarts. Where does it resume from, and what does the feed look like for the first 30 seconds?
Why do you want to join P99soft specifically?
Why do you want to join P99soft specifically?
Approach
- Name the grain you start from and join outward from it.
- Check whether any join is one-to-many before aggregating, or the sums inflate.
- Say which index the query would use, and what makes it unusable.
- Handle the rows that do not match: that is usually the actual question.
Follow-up
- How does the query change if that join becomes one-to-many?
- What happens to this when the table is ten times larger?
Explain why the owner filter ignores the listing index
The only index on resource is (tenant_id, status, updated_at DESC, resource_id DESC). A new endpoint returns one user's resources across all statuses, newest created first: WHERE tenant_id = $1 AND owner_user_id = $2 ORDER BY created_at DESC LIMIT 20. On a tenant with 2M rows it takes 900 ms and EXPLAIN shows a sort above a large scan. Explain precisely why the existing index cannot serve it, give the index that can, and state which of these the new index still will not help: owner_user_id alone across tenants; the same query ordered by updated_at. PostgreSQL 16.
Approach
- Separate the two jobs an index does. For filtering, a composite btree is seekable only on a left prefix, so with no predicate on status the scan can at best range over tenant_id and test owner_user_id per row; PostgreSQL 16 has no btree skip scan to jump the unconstrained column.
- For ordering, the index is sorted by (status, updated_at) within a tenant and not by created_at, so the LIMIT cannot stop early: every matching row is read and then sorted. That is the 'Sort Method: top-N heapsort' line, and it is why the plan reads 2M rows to answer with 20.
- Derive the replacement from the access path — equality, equality, then the ordering column: CREATE INDEX CONCURRENTLY ON resource (tenant_id, owner_user_id, created_at DESC). The scan seeks to the (tenant, owner) range and walks 20 entries in order, so the Sort node disappears along with the row-read.
- Treat INCLUDE (title, status) as conditional, not free. An index-only scan still visits the heap for any row whose page is not marked all-visible, so on a table taking 1.2k writes/second the win depends on autovacuum keeping the visibility map current, and the wider index costs more on every insert.
Follow-up
- 90% of rows are status='active'. Would a partial index WHERE status = 'active' change your answer, and for which of the three queries?
- A dashboard runs this for 40 owners in one page load. What changes about the design?
Can you explain the core pillars of OOP and how you apply them in your daily work?
Can you explain the core pillars of OOP and how you apply them in your daily work?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
What is the difference between specific Java keywords (e.g., static vs. final)?
What is the difference between specific Java keywords (e.g., static vs. final)?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Describe the structure of a class and how you determine method visibility.
Describe the structure of a class and how you determine method visibility.
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
How do you construct and optimize SOQL queries for large datasets?
How do you construct and optimize SOQL queries for large datasets?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Describe your experience building and securing REST API integrations.
Describe your experience building and securing REST API integrations.
Approach
- Say who the caller is and what they do when the call fails halfway.
- Define the identity of a request so a retry cannot double-apply it.
- Separate accepted, pending, failed and confirmed; they are different facts.
- Design the error taxonomy before the success shape; callers branch on it.
Follow-up
- What happens if the caller retries after a timeout?
- How does a client discover it is on an old version of this contract?
Can you walk me through a complex integration task you have performed in a CRM or ERP environment?
Can you walk me through a complex integration task you have performed in a CRM or ERP environment?
Approach
- Say who the caller is and what they do when the call fails halfway.
- Define the identity of a request so a retry cannot double-apply it.
- Separate accepted, pending, failed and confirmed; they are different facts.
- Design the error taxonomy before the success shape; callers branch on it.
Follow-up
- What happens if the caller retries after a timeout?
- How does a client discover it is on an old version of this contract?
Listing latency scales with page size, not with filters
The tenant listing endpoint reads resource filtered by tenant_id and status, ordered by updated_at DESC, and returns each row plus the owner's display name from app_user and the actor of that resource's latest resource_revision. p99 is 55 ms at 10 rows per page and 1.4 s at 200. Database telemetry shows 401 statements per request, each under 1 ms, and nothing in the slow-query log. Diagnose the cause and give the fix, stating the statement count per request and the p99 you expect afterwards.
Approach
- Read the counters before forming a theory. 401 statements for 200 rows is one driver query plus two per row, and sub-millisecond execution with an empty slow-query log rules out a bad plan. The time is round trips, which is why it is invisible in every per-query metric and scales with rows returned rather than with filter selectivity.
- Name the two per-row statements from their normalised text: a single-row app_user lookup by user_id, and a resource_revision lookup by resource_id ordered by version DESC LIMIT 1. Confirm by dropping those two response fields and watching the statement count fall to one. That locates the calls in the serialisation layer, not the repository.
- Check that the arithmetic accounts for the whole gap. Measure one round trip to the replica in isolation; 400 trips at roughly 3 ms of network plus 0.2 ms of execution is about 1.3 s on top of a 55 ms baseline, which matches. If the multiplication had fallen short, the N+1 would only be part of the story and you would keep looking.
- Batch both lookups. Collect owner_user_ids and resource_ids from the driver query, then issue WHERE tenant_id = $1 AND user_id = ANY($2) for the users, and PostgreSQL's SELECT DISTINCT ON (resource_id) ... WHERE resource_id = ANY($2) ORDER BY resource_id, version DESC for the latest revision, which the UNIQUE (resource_id, version) index serves directly. On an engine without DISTINCT ON, use a lateral join or a row_number window. Three statements per request at any page size.
Follow-up
- The page size is capped at 200 today. What breaks first if it is raised to 2,000, and is it still this bug?
- How do you stop the next N+1 from reaching production, given that no individual query is slow and the endpoint's tests pass?
Built from the rounds and topics P99soft candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the P99soft loop
- Write out the reported sequence: High-Level Technical Screening, Deep-Dive Assessments, Conversation with Leadership.
- For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.
Deliverable: A one-page map of the 3 reported rounds, with the weakest marked.
02Work Java
- Spend the session on Java, which P99soft candidates report being tested on.
- Write one worked example in Java and time yourself on it.
Deliverable: One timed worked example in Java.
03Work Salesforce
- Spend the session on Salesforce, which P99soft candidates report being tested on.
- Write one worked example in Salesforce and time yourself on it.
Deliverable: One timed worked example in Salesforce.
04Work OOP / Object-Oriented Programming
- Spend the session on OOP / Object-Oriented Programming, which P99soft candidates report being tested on.
- Write one worked example in OOP / Object-Oriented Programming and time yourself on it.
Deliverable: One timed worked example in OOP / Object-Oriented Programming.
05Answer out loud: Technical Fundamentals and OOP
- Answer aloud, timed: Can you explain the core pillars of OOP and how you apply them in your daily work?
- Answer aloud, timed: What is the difference between specific Java keywords (e.g., static vs. final)?
Deliverable: Spoken answers to 2 reported Technical Fundamentals and OOP question(s), under time.
06Answer out loud: Platform-Specific Proficiency (Salesforce/NetSuite)
- Answer aloud, timed: How do you construct and optimize SOQL queries for large datasets?
- Answer aloud, timed: Describe your experience building and securing REST API integrations.
Deliverable: Spoken answers to 2 reported Platform-Specific Proficiency (Salesforce/NetSuite) question(s), under time.
07Answer out loud: Behavioral and Managerial
- Answer aloud, timed: Tell me about a time you had to resolve a technical bottleneck under a tight deadline.
- Answer aloud, timed: How do you approach feedback from a manager or a client?
Deliverable: Spoken answers to 2 reported Behavioral and Managerial question(s), under time.
Expand any day for tasks and deliverables. Your progress is saved on this device.
Behavioural rounds judge the decision you made and what it cost.
How do you handle authentication and error handling when connecting external systems?
How do you handle authentication and error handling when connecting external systems?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
Tell me about a time you had to resolve a technical bottleneck under a tight deadline.
Tell me about a time you had to resolve a technical bottleneck under a tight deadline.
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
How do you approach feedback from a manager or a client?
How do you approach feedback from a manager or a client?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
- 01
How do you handle authentication and error handling when connecting external systems?
- 02
Tell me about a time you had to resolve a technical bottleneck under a tight deadline.
- 03
How do you approach feedback from a manager or a client?
How long does the entire interview process usually take?
The process is designed to be quick, typically moving from the initial coding test to the final round within a few weeks.
P99soft Software Engineer candidate reports ↗Is the technical round focused on whiteboarding or practical coding?
Expect a mix of both; you will be asked to solve coding problems in a live environment and discuss your approach to system-level design.
P99soft Software Engineer candidate reports ↗What is the best way to stand out?
Show that you understand the business context of your code. An engineer who asks "How does this solve the client's problem?" is far more valuable than one who only asks "How do I write this function?"
P99soft Software Engineer candidate reports ↗What topics does P99soft test in interviews?
P99soft interviews most often cover Java, Salesforce, OOP / Object-Oriented Programming, SOQL (Salesforce Object Query Language), and REST APIs. The exact emphasis depends on the specific role you apply for.
P99soft Software Engineer candidate reports ↗Sources & methodology 3 sources ↗
No official company page is cited. Rounds and questions come from candidate reports and PracHub editorial material; each source shows the date it was read.
- 01P99soft Software Engineer candidate reports ↗
Company-reported rounds, questions and FAQ.
Candidate reports · Accessed 2026-09-22 - 02PracHub Software Engineer practice ↗
PracHub practice material, not company-reported.
PracHub page · Accessed 2026-09-22 - 03PracHub preparation framework ↗
PracHub preparation guidance.
PracHub page · Accessed 2026-09-22
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