William Pietri Startup CTO and Lean Startup expert

I reached out to William personally after having read his writings online. I am glad I did because he provided me with a perspective that I would have had a hard time reaching on my own, emphasizing key basic strategies on sound business development. I will be following his advice and checking back with him on updates. William, thank you very much!

William was my mentor at the Lean Startup Machine event in Palo Alto in Jan 2012. Drawing upon his lean startup experience, he served as my mentor to help me take a mere concept of a tech business to a barebones product and get customer feedback within a weekend.

I was impressed by William's ability to see the different components of the business model associated with my original vision, break it down, and test all of my assumptions with well designed methods to get customer feedback.

After many iterations of this process with William's continued guidance, Boxbee (my startup) has enjoyed rapid growth with many happy customers

William was a fantastic mentor to us. His knowledge of lean startup techniques is fantastic, and he spans the gap between technical and business concerns incredibly well. He asked a number of key questions and suggested some key approaches that still mold the entrepreneur I've become almost two years later. It was in part through interacting with him during LSM and several times afterwards that I decided that it was time to make the leap to become an entrepreneur.

William is a passionate and knowledgeable practitioner of Lean Startup methodologies. His approach is practical and he's universally helpful to the teams he works with.

We're grateful to have had him as a mentor and keynote speaker at the Lean Startup Machine workshops in the San Francisco Bay Area.

William and I worked together at NeedFeed for a year. During that time he taught me a great deal about building a strong team and making a development process from scratch. He knows how to hire great talent, is wonderfully connected within the industry and is keenly interested in delivering usable, extensible software. He's also one of the most straight-forward people I've ever worked with, not afraid to tell you what he thinks, why, and to back it up with experience and deep knowledge. Working with William has undoubtedly made me a more precise, informed and creative engineer.

We contracted William to project manage the development and deployment of an important and complex software feature for the English Wikipedia. He did so from October 2009 to June 2010, when the feature was successfully deployed. Wikipedia is a challenging environment with a very vocal and passionate user community, and William managed the project with exceptional professionalism throughout. He is diligent, highly capable and a great communicator. He made the process transparent for everyone to follow. Most importantly, William manages the important balance of developing excellent work relationships without sacrificing quality of product and process. Based on our experience, I highly recommend working with William.

Simply one of the best software engineers that I've worked with; taught me alot, and is really fun to work with. I wish I could get him to come work for me again. Also, if you're thinking of doing XP, you need this guy!

William hired me for a greenfield XP project that turned out to be both the most fun and the most productive experience I've had so far. William was serving as adviser to the management, and was also a full member of the development team, so we got to pair program together extensively. As well as being fun and productive, this was also the time when I learned as much or more from the folks I was working with as I shared with them. William and the others he hired were all amazing programmers and supportive teammates.

William is technically savvy enough to understand and evaluate a wide variety of technologies. He's good not only at explaining how to make better technology and process choices, but sitting down with other technical staff to implement those choices. When I was on the team he was leading, he was key to helping the decision makers decide what software they needed, and working with the technical team to deliver it. We delivered working software which met the objectives that the product manger and management defined.

William is a rare find. He combines expertise in technical architecture, programming across a range of languages, is an excellent mentor to team members, and has extensive knowledge of software development methodologies including agile(XP). William has helped to kick-start several of my projects, building stable, scalable and very fast applications.