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Cal Henderson

Cal Henderson

Co-founder & CTO / Slack Technologies, Inc

CountryUnited States
EducationBSc, Birmingham City University
Known ForCMS, JavaScript, APIs, Mobile Applications, PHP, MySQL, Web Development, Scalability
Instagram888
Twitter
LinkedIn5.5K
TechnologyProgrammation
Slack Tenure
15 Years
LinkedIn Followers
5.5K
Instagram Followers
888
Book Published
1
Search More

About Cal Henderson

Cal Henderson is the Co-founder and former CTO of Slack, a leading platform for modern team communication, which he helped build from inception through its IPO and subsequent acquisition by Salesforce. An experienced technology leader, he previously served as the Head of Engineering at Flickr, which was acquired by Yahoo. He is also the author of the best-selling book "Building Scalable Websites."

Career

Slack Technologies, Inc
Slack Technologies, Inc

Co-founder & CTO

Apr 2009 - Mar 2024
Responsibilities

Went public in 2019, acquired by Salesforce in 2021

Flickr
Flickr

Head of Engineering

Dec 2003 - Apr 2009
Responsibilities

Built at Ludicorp, acquired by Yahoo in 2005

EMAP
EMAP

Director of Technology

Aug 2001 - Feb 2004
Position

Director of Technology

Education

Birmingham City University
Birmingham City University

BSc

Field of Study

BSc - Software Engineering

Sharnbook Upper School
Sharnbook Upper School
Education

N/A

Skills

Core technical and professional competencies derived from leading engineering teams at high-growth companies like Slack and Flickr.

Technical Skills

Scalability

System Architecture

Web Development

APIs

PHP

MySQL

JavaScript

CMS

Mobile Applications

Leadership & Strategy

CTO Leadership

Engineering Management

Product Strategy

Team Building

Technical Due Diligence

Public Speaking

Creative & Communication

Authoring

B3TA Co-creation

Creative Community Building

Technical Writing

Domains

Primary

Enterprise Software, Team Communication, SaaS, Cloud Computing

Secondary

Social Media, Digital Photography, Web Infrastructure, Gaming

Tags

Personality

Visionary, Technical Leader, Author, Pragmatic, Builder

Focus

Scalability, Engineering Culture, Product-Focused, Open Source Contributor

Recent Content

Bandit BabyBandit Baby
Bandit Baby

Bandit Baby

2018-06-28
94 likes
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William Franklin HendersonWilliam Franklin Henderson
William Franklin Henderson

William Franklin Henderson

2018-06-26
131 likes
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Conference timeConference time
Conference time

Conference time

2018-05-23
49 likes
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Totoro cream puffs

Totoro cream puffs

2018-05-05
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Instagram PostInstagram Post
Instagram Post

2018-05-05
31 likes
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Frequently Asked Questions

A robotic, objective summary of Cal Henderson's career focusing on his co-founding role at Slack and his previous tenure at Flickr.

What is Cal Henderson's role at Slack?

He is the Co-founder and former CTO of Slack Technologies, Inc., a position he held from the company's inception in April 2009 until March 2024.

Was Cal Henderson Head of Engineering at Flickr?

Yes, he served as the Head of Engineering at Flickr from December 2003 until April 2009, prior to co-founding Slack.

Did Cal Henderson write "Building Scalable Websites"?

Yes, he is the author of the best-selling book "Building Scalable Websites," which details engineering and technology practices.

How long was Cal Henderson at Slack Technologies?

Cal Henderson was with Slack Technologies, Inc. for approximately 15 years, from its founding in April 2009 through March 2024.

What happened to Slack Technologies, Inc.?

Slack Technologies, Inc. went through an IPO and was subsequently acquired by Salesforce. Cal Henderson helped build the platform through this acquisition.

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