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Abstract This paper presents design improvements, performance results and lessons learned from deploying deep (≥14,000 ft) coiled tubing-based artificial lift systems – velocity strings (VS) and coiled tubing gas lift (CTGL) – in mature gas-condensate wells of the Piedemonte Basin. These rigless interventions were implemented to mitigate liquid loading, maintain production in high-pressure environments, extend the economic life of critical assets, and assure gas supply to meet market demand. Candidate wells were selected through nodal analysis and production forecasting to anticipate critical velocity rates. VS systems were installed using coiled tubing to reduce liquid holdup and restore flow in low-rate wells, while maintaining functionality of the tubing retrievable downhole safety valve (TRSSV). CTGL systems were installed in wells with moderate to high liquid production (>1,300 BPD), where gas injection was available. Multiple configurations—stainless steel (~19.9Cr) and carbon steel coiled tubing combined with dual-flow safety valves and different BHA designs—were evaluated to assess performance, corrosion rates, run life, and reliability under CO₂ conditions with paraffin deposition tendencies. The implementation of coiled tubing based artificial lift systems was carried out in two phases. First, from 2016 to 2020, early pilots of VS and CTGL faced operational and material challenges, including corrosion-related failures, paraffin deposition, and limited run life, resulting in low economic returns. These experiences provided critical insights and lessons learned such as:-Early Intervention is critical: Installing VS or CTGL before loss of lifting capacity significantly improves success and production rates.‒Hybrid flow configurations: Allowing flow in multiple ways as only coiled tubing, annular coiled tubing-tubing, and only annular enhances flexibility.-Material selection matters: Using Stainless Steel (19.9 Cr) Coiled tubing mitigates corrosion in high-CO2 environments-Operational adaptability is essential: Addressing paraffin buildup and gas injection rates through designs and field iterations improves system performance.-Candidate selection and planning: Proactive identification of wells and standardized designs reduce costs and intervention time. Building on these lessons, VS and CTGL installed during 2020-2025 achieved a success rate of 80% for VS and 100% for CTGL. A total of 11 VS and 15 CTGL were deployed, extending well life by 18-24 months for VS and 36-48 months for CTGL, delivering 6.3 million BOE of incremental recovery. This paper presents a replicable model for extending mature gas condensate field life using coiled tubing technologies tailored to liquid-loaded gas wells. It contributes new insights into rigless deployment strategies, material optimization, and adjustments for HPHT environments. These findings advance the state of knowledge on artificial lift, offering a scalable solution that supports energy transition goals through enhanced gas recovery.