As lead engineer for more than 20 projects, Tiffine Koch managed 14 other engineers at a Walmart office in Sunnyvale, and fired two — but in spite of her management duties, she was never officially made a manager, she said in a new lawsuit.

Walmart’s failure to promote her, and to pay her a salary matching her responsibilities at the firm’s e-commerce operation in Sunnyvale, occurred because she’s a black woman, Koch claimed in the suit.

Walmart said it does not tolerate discrimination of any kind, and the firm denied Koch’s allegations, calling them “unfounded.”

Koch claims in her suit that she was “continually paid less than her two male colleagues who were performing the same managerial tasks and managing approximately the same number of people,” said the suit filed in Santa Clara County Superior Court.

“One of these employees was actually managing less people than (Koch), and yet was still earning more money than her.”

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Out of “hundreds” of employees in Walmart’s Sunnyvale offices, only two were African American, said the suit filed July 11. Koch also claims she was demoted after she complained to the company about alleged discrimination.

Hired in May 2016, Koch resigned in June. Her suit charges Walmart with “making her workplace so intolerable that she had to resign.”

Walmart disputed Koch’s assertion that she managed 14 engineers.

“We are contesting that,” said spokesman Randy Hargrove. “While she was employed with us she had no associates directly reporting to her.”

Walmart also said that it had promoted Koch to a job with greater pay and responsibility, after she’d been with the company for less than a year.

She is seeking lost wages and unspecified damages. Walmart said it would defend the company against her claims.