Developed Time To First Token (TTFT) tracking for the deepset-ai/haystack-core-integrations repository by extending the Langfuse tracer to capture and log completion_start_time, providing detailed latency insights up to the first token. The implementation included robust validation for time formats and safeguards to skip logging when invalid start times are detected, reducing noise in trace data. Addressed linting issues to ensure code quality and continuous integration compliance. This work, utilizing Python and integration development skills, improved observability and enabled more precise latency analysis for token-level performance, supporting faster troubleshooting and optimization of end-user prompt response times within the system.