Mayur Patel
Feb 26, 2026
6 min read
Last updated Feb 26, 2026

Instream’s legacy CRM was modernized, migrated to Kubernetes, and enhanced with stable email and collaboration integrations, without disrupting existing users or breaking production workflows. This engagement focused on upgrading a running system to modern engineering standards while preserving data integrity, operational continuity, and the stability that sales teams depended on daily.
Instream is a CRM platform built to help sales professionals manage relationships, communication, and pipeline activities efficiently. Linearloop partnered directly with CEO Filip Duszczak and the DevOps lead to refactor a complex Django-based legacy codebase, optimize backend performance, migrate infrastructure to DigitalOcean using Kubernetes orchestration, and seamlessly integrate Google and Microsoft communication tools into the CRM. The objective was clear: Improve scalability, reliability, and user experience without compromising the live system already in use.
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Instream is an established CRM platform built to support sales teams in managing relationships, tracking communication, and organizing pipeline activities within a single structured system. The product was already live, actively used by businesses, and embedded into daily sales workflows, which meant any changes had to be implemented without disrupting ongoing operations.
The company is led by CEO Filip Duszczak, who served as the primary stakeholder throughout the engagement. With an existing user base and a functioning product in production, the focus was on strengthening, stabilizing, and modernizing a system that sales teams already relied on for core business processes.
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The project operated under strict constraints, where system stability was non-negotiable, and every change had to be introduced without disrupting active users. The complexity came from the need to modernize a live production environment safely.
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Success for Instream was defined by stability first, not feature expansion. The CRM was already in active use, so the primary expectation was that modernization efforts would not introduce regressions, performance degradation, or workflow interruptions. Preserving system reliability while improving it was the baseline requirement.
Seamless resolution of email and calendar integration issues was equally critical. Communication workflows had to function without friction across Gmail, Outlook, and calendar systems, ensuring sales teams could operate without technical barriers.
Improved usability also mattered. Navigation, responsiveness, and backend optimizations are needed to translate into a smoother day-to-day experience for users. Finally, infrastructure readiness was a strategic goal. Moving toward Kubernetes-based deployment and modern DevOps practices required strengthening scalability and resilience while ensuring zero disruption during the transition.
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Modernizing a live CRM introduced technical risk at multiple layers, particularly because the system was already in production and actively used by customers. The highest risk areas were embedded in legacy architecture, infrastructure transitions, and deployment orchestration decisions.
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The CRM was built on a mature and production-tested stack that supported both transactional workflows and background processing requirements. Rather than introducing a completely new architecture, the focus was on strengthening and optimizing the existing foundation while aligning it with modern deployment standards.
Each layer of the stack played a defined role in maintaining performance, scalability, and operational control during modernization and infrastructure transition. The backend handled business logic and task orchestration, the frontend supported structured user interactions, and the infrastructure layer ensured controlled deployment and scalability under Kubernetes.
| Layer | Technology |
| Backend | Python |
| Web Framework | Django |
| Task Queue | Celery |
| Frontend | Angular |
| Database | PostgreSQL |
| Caching | Redis |
| Container Orchestration | Kubernetes (K8s) |
| Cloud Infrastructure | DigitalOcean |
The engineering approach prioritized controlled evolution over disruptive change. A careful refactoring strategy was implemented to understand legacy Django components before modifying them, ensuring that business logic and existing workflows remained intact. Improvements were introduced incrementally, with targeted code optimizations rather than large-scale rewrites, reducing regression risk and preserving system stability throughout the modernization process.
On the infrastructure side, DevOps pipelines were structured to enable predictable, repeatable deployments under Kubernetes. The system was modernized at the orchestration and hosting layers without an architectural overhaul, minimizing operational risk while improving scalability and deployment control. This approach strengthened reliability and future readiness without destabilizing the live production environment.
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The project followed a structured Agile model to manage modernization within a live production environment, where controlled iteration was more critical than speed. Execution focused on disciplined delivery, continuous validation, and cross-functional coordination to prevent disruption while introducing improvements.
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Communication workflows are central to any CRM, which made third-party integrations a functional priority rather than an optional enhancement. The objective was to stabilize existing connections, eliminate friction in daily sales activities, and introduce collaboration capabilities directly within the CRM interface.
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The impact of the engagement was measured through system resilience, operational control, and user workflow stability rather than vanity metrics. The CRM transitioned from a legacy-bound system to a modernized, deployment-ready platform while remaining fully operational throughout the process.
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Client feedback focused on execution discipline and stability. The legacy system was upgraded without disruption, and the refactoring approach preserved existing workflows while improving reliability. Confidence increased not because features were added, but because the system remained stable throughout modernization.
The Kubernetes migration strengthened infrastructure readiness and deployment control, positioning the CRM for scalable growth. With the final launch phase pending, work continues on enhanced reporting and communication features. Linearloop remains engaged as a long-term partner, supporting the platform’s evolution while safeguarding operational stability.
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Modernizing a live legacy system requires more than technical upgrades; it demands disciplined engineering, controlled execution, and zero tolerance for disruption. This engagement strengthened Instream’s CRM at the code, infrastructure, and integration layers while keeping production stable and users uninterrupted.
If your platform is running on legacy architecture but cannot afford downtime or risk, the right modernization strategy makes the difference. Reach out to Linearloop to build a scalable, production-safe transformation roadmap tailored to your system.
Mayur Patel, Head of Delivery at Linearloop, drives seamless project execution with a strong focus on quality, collaboration, and client outcomes. With deep experience in delivery management and operational excellence, he ensures every engagement runs smoothly and creates lasting value for customers.