Client reviews

Client experience across Emerald’s history.

Verified Upwork reviews document completed projects from recent years. Direct testimonials preserved from Emerald’s former website show that the same care, expertise, persistence, and respect for clients’ money have defined the company from its early years.

Understanding the project

Clients describe the care Dave takes to understand what they are trying to accomplish before and during development.

5.0
“David is a fantastic developer! He is amazingly fast and yet truly takes the time to understand exactly what you are hoping to achieve.”
Upwork clientCustom TradeStation chart study · 2021
5.0
“Did a great job and was very fair. I wouldn’t hire anyone else to do programming except David! He is extremely educated in what he does.”
Upwork clientProgrammer · 2020–2021
5.0
“Dave is the consummate professional. He spent the time to make sure we understood what we would be getting. Would use again.”
Upwork clientSeeking a TradeStation EasyLanguage programmer · 2020

Continuing work and reliability

Several reviews come from clients who continued working with Dave over multiple contracts or over a period of years.

5.0
“I have worked with Dave for years and he is the best in the business. He is always on time and delivers fantastic work. He has tremendous knowledge and experience.”
Upwork clientTradeStation programming help · 2020–2025
5.0
“Very professional and great to work with. I just opened another contract with David.”
Upwork clientImporting options information into EasyLanguage · 2022–2025
5.0
“Very knowledgeable and completed projects on a timely basis”
Upwork clientTradeStation indicator · 2021

Development and automation

Clients speak directly to Dave’s EasyLanguage and TradeStation knowledge across development, automation, and order handling.

5.0
“Trading options is complicated. Dave made it feasible for a non-coder to operate successfully.”
Upwork clientTradeStation development for equities and options · 2025–2026
5.0
“If you’re trading on TradeStation and want to automate any part of your trading, call Dave for help. There’s none better.”
Upwork clientTradeStation development for equities and options · 2022–2025
5.0
“Great job; very timely; we definitely would hire David again.”
Upwork clientDLL referenced by EasyLanguage code · 2019
5.0
“David is a topnotch EasyLanguage developer and I recommend his highly.”
Upwork clientTradeStation/EasyLanguage order handling · 2020
5.0
“Dave has excellent TradeStation/EasyLanguage skills and I would not hesitate to use him again. His services are highly recommended.”
Upwork clientDebug TradeStation/EasyLanguage order handling · 2019–2020
5.0
“Mr. David Cohn is extremely skill and professional, easy to work with and patient. First class all the way!”
Upwork clientEasyLanguage trading system programming · 2019

Help, tutoring, and problem solving

These clients came to Dave for explanation, troubleshooting, or personal EasyLanguage help.

5.0
“I always got very professional help by David, he got me out of dead ends that I couldn’t resolve. Can fully recommend working with him!!!”
Upwork clientEasyLanguage programming tutoring · 2022–2025
5.0
“Well worth the money, definitely knows his stuff. I have been using Tradestation for 20 years.”
Upwork clientEasy Language help · 2020
5.0
“David Cohn was extremely helpful with improving and debugging an EasyLanguage script.”
Upwork clientEasyLanguage script development · 2019–2020
5.0
“Dave is fantastic on all levels and extremely knowledgeable about tradestation. Will come back for more work when needed.”
Upwork clientTradeStation orientation · 2020

About the Upwork reviews: The wording shown above is reproduced from Emerald’s Upwork job history. Client names are not displayed in the public completed-job listing. Only reviews whose complete wording was visible in the supplied Upwork record are included.

What traders have said over the years

A reputation established long before the latest review.

These testimonials were supplied directly by Emerald clients and published on Emerald’s former website. Light editing for spelling, punctuation, and length preserves the clients’ meaning and voice.

Direct client testimonial

“I’m an advanced TradeStation user and Dave has helped me automate three of my system’s processes on TradeStation. He came highly recommended from my broker, and I’m glad I went with him. What you can expect is a direct communicator, who makes sure he understands first and communicates second. His speedy replies, ways around unforeseen hurdles, and insights into my project’s requests were greatly appreciated. My project took seventeen revisions. With each step, Dave was focused on the task at hand, nimble in response to changes in specifications, and never lost his enthusiasm and professional demeanor.”
N.S.Framingham, Massachusetts · Previously published by Emerald

Direct client testimonial

“Simply the best! Dave did what everyone else said could not be done. He is amazing. My custom job was completed on schedule and within budget. Truly a great customer experience. I highly recommend Emerald Trading Technologies, Inc.”
Victor SalamoneHolbrook, New York · Previously published by Emerald

Direct client testimonial

“I highly recommend Emerald Trading Technologies to any trader. The process was carefully explained in our first conversation, and from that moment on I was extremely impressed with their professionalism. I am now on my third project with them. There is no wasting of time, and they are always looking for better ways to keep costs down—which is always appreciated. The finished product has been nothing short of stellar. I will be working with them for a long time to come.”
Jason F.Dundee, Michigan · Previously published by Emerald

About these historical testimonials: They were supplied directly to Emerald for publication and appeared on Emerald’s former website. They are presented separately from independently submitted Upwork reviews.

Start with the idea

Tell Dave what you are trying to accomplish.

You do not need to arrive with a fully defined specification. Emerald works with you to turn the idea in your head into precise requirements and working EasyLanguage code.

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