Principal Software Engineer - Backend
Backend engineering role on dubizzle Labs' classifieds platforms in Pakistan, covering service design and architecture for high-traffic systems. Suits very experienced backend engineers ready to lead technical direction; the posting itself gives no further detail.
Karachi
On-siteSix or more years of experience.
Pay not stated
Full-time
Posted 15 Sept 2026What they ask for
How Dubizzle Labs hires
- 1
HR round
Recruiter screen · Candidate reported
- 2
Technical round one
Technical interview · Candidate reported
Core language knowledge, frameworks and general software engineering concepts.
- 3
Technical round two
Technical interview · Candidate reported
Reported to include designing a database schema from a set of requirements.
- 4
Final round
Hiring manager · Candidate reported
What comes up
Roadmaps and cheat sheets for this role
Matched to the skills and level this job asks for.
- RoadmapBackend developmentAPIs, databases, auth, deploys
- RoadmapSystem designSystems that scale
- RoadmapDSA and problem solvingData structures and patterns
- Cheat sheetBackend developmentAPIs, databases, auth, deploys.
- Cheat sheetSystem designSystems that scale.
- Cheat sheetDSA and problem solvingData structures and patterns.
Worth reading before you apply
From the Sefism resource library, matched to this role and Dubizzle Labs's rounds.
A foundations course that builds eleven core data structures from the ground up (arrays, matrices, stacks, queues, linked lists, trees and BSTs, hash tables, hash sets, heaps, graphs and tries), then covers sorting, searching, greedy and divide and conquer. Every chapter has practice problems, flashcards and an assessment. It suits students and career switchers whose foundations came from tutorials and who find pattern courses move too fast.
- Job search
- DSA
- CS fundamentals
A short text course on algorithm analysis: all five asymptotic notations, time and space complexity, best, worst and average cases, and three methods for recursive complexity including the master theorem. It suits students and self-taught developers who can write working code but freeze when an interviewer asks for the time and space complexity, or who want to understand why one solution is faster than another.
- Job search
- DSA
- CS fundamentals
The second volume of Grokking the System Design Interview, aimed at senior and staff (L5/L6) design rounds. It works through harder case studies such as a payment system, flash sale, notification service, unique ID generator, Gmail, Reddit, Google Calendar and a code judging system, then goes beneath them with patterns like quorum, write-ahead logs and vector clocks and deep dives into Dynamo, Cassandra, Kafka, Chubby, HDFS, GFS and BigTable.
- System design
- Backend
- Job search
The original Grokking system design course, which made the design round learnable. It teaches a repeatable interview approach and the key trade-offs (SQL versus NoSQL, strong versus eventual consistency, REST versus RPC and more), then works through 15 classic designs such as a URL shortener, Instagram, Dropbox, Twitter, YouTube, a rate limiter, a web crawler, Uber and Ticketmaster, each with requirements, estimates and trade-off discussion.
- System design
- Job search
- Backend
A very large site of articles on data structures, algorithms and core CS subjects such as operating systems, DBMS, computer networks and OOP, usually with code in several languages, plus practice problems and paid courses. It is handy for revising a university topic or finding a worked example of a specific algorithm. Quality varies because much is community written, so cross-check anything surprising against a textbook or official documentation.
- DSA
- CS fundamentals
- Databases
An eight-stage roadmap through the core CS subjects: how a computer runs a program, OOP and design, operating systems, computer networks, database theory and internals, software engineering and theory, finished with a systems project such as a shell, an HTTP server or a tiny database. It suits CS students and self-taught developers filling the same gaps, and favours understanding shown in working code over memorised answers.
- DSA
- CS fundamentals
- Databases
The full description, requirements and how to apply are on the company's own posting. This page is a summary so you can decide whether it is worth opening.
Verification
3 of 4 checks- Company verified
- Posting checked
- Still open
- Not confirmed by the company
Last checked 9 days ago (6 Oct 2026)
About the company
The Pakistan engineering arm of the Dubizzle group, building the technology behind Zameen, Bayut, OLX and dubizzle from Lahore, Karachi and Islamabad.
How Dubizzle Labs hiresFollow along
New writing, resources and project ideas land here first.