Sr. Software Engineer/ Backend

Our Direct client is looking for Sr. Software Engineer/ Backend for a contract role. If Interested Please find the JD below and share your updated resume in word format. Thank You. Title: Sr. Software Engineer/ Backend Location: Remote Duration: 6 Months Contract Job Details Job Title: Sr. Software Development Engineer/Backend Job Description What You’ll Be Part Of: This is the revenue-facing edge of our data platform: partner-facing feeds, identity matching, and the pipelines that deliver them at scale and on time. We're engaging a senior contract engineer to help deliver on high-impact, time-bound initiatives — including migrations to new data methodologies, deterministic identity matching using unique IDs, and new partner optimization feeds. You'll own meaningful pieces of the stack end to end: from Spark pipelines and our data lake through workflow orchestration, partner integrations, and the APIs and delivery mechanisms that deliver signal to partners. This is a hands-on delivery role for someone who can ramp quickly and produce production-quality work with minimal onboarding. Responsibilities: ● Build, optimize, and operate production Apache Spark pipelines that generate attributed conversion and optimization feeds from large-scale impression and conversion data. ● Design and evolve data processing and models across modern data lake and warehouse technologies, orchestrated with a production workflow scheduler on AWS. ● Build and operate partner optimization feeds and integrations with external partners, including schemas, identity fields and unique IDs, file delivery, reconciliation, and SLAs. ● Build, change, and operate production REST APIs, including PHP APIs, delivering secure, backward-compatible changes end to end (implementation, validation, authorization, data access, documentation, automated testing, and production diagnostics). ● Trace and modify behavior across controllers, database queries, templates, JavaScript, and automated tests. ● Diagnose production failures, reconcile partner-facing data, execute backfills, and manage staged releases and rollbacks. ● Write and maintain unit and integration tests across pipelines, APIs, and feeds. Qualifications and Education Requirements: ● 7+ years of professional software or data engineering experience. ● 4+ years building, optimizing, and maintaining production Apache Spark pipelines, with strong Java and Python skills across JVM Spark and PySpark. ● Advanced SQL, relational data modeling, and large-scale data processing experience, including production work with Snowflake, MySQL, and Iceberg. ● 3+ years operating AWS data workloads using S3 and Airflow (or equivalent production workflow orchestration); container orchestration and data-catalog experience a plus. ● 3+ years building, changing, and operating production REST APIs, including PHP APIs built with Symfony or a closely equivalent PHP MVC framework. ● Demonstrated proficiency using AI development tools to deliver production-quality work efficiently — including AI-assisted coding, code review, documentation, and investigation, working with agentic code harnesses, and spec-based (spec-driven) AI development — with the judgment to know when to rely on AI output and when not to. ● Ability to independently deliver secure, backward-compatible API changes, including implementation, validation, authorization, data access, documentation, automated testing, and production diagnostics. ● Experience implementing external provider or client integrations involving schemas, APIs, file delivery, identity fields, reconciliation, privacy-sensitive data, and SLAs. ● Production full-stack experience with PHP, Symfony (or a comparable framework), Doctrine, Twig (or another server-rendered template system), and JavaScript. ● Ability to trace and modify behavior across controllers, database queries, templates, JavaScript, and automated tests. ● Experience writing unit and integration tests for data pipelines, APIs, and web applications. ● Ability to diagnose production failures, reconcile data, execute backfills, manage staged releases and rollbacks, and support delivery commitments. ● Hands-on experience building and running big data systems, with a focus on performance, reliability, and data quality. ● Experience in ad tech or advertising measurement, such as attribution, conversions, audience and impression data, identity matching, or partner optimization feeds. ● Ability to ramp quickly and deliver with minimal onboarding in an existing, complex codebase. Preferred Skills: ● Direct experience building partner optimization or advertising feeds with external platforms (DSPs, publishers, or measurement partners). ● Experience with deterministic and probabilistic identity matching — unique IDs, device IDs, IP-based matching, and identity graphs. ● Familiarity with edge/log delivery infrastructure and pixel/impression tracking. ● Experience with data lake table formats and query engines at large scale. ● Experience with privacy and compliance-driven data workflows (deletion, opt-out, suppression, data retention). ● Comfort operating in uncharted territory — turning ambiguity into production systems without a detailed guide. We are an Equal Opportunity Employer