Terraform’s Fork Got the Code but Had to Bring Its Own Engineers

Terraform turns infrastructure into a file

A company running software in the cloud needs servers, databases, networks and permissions, often from several providers. Clicking through each provider’s console is slow and hard to repeat. Terraform lets an engineer describe all of it in text files, then works out what has to be created, changed or deleted to match. The files can be reviewed and versioned like any other code. HashiCorp, the company behind Terraform, also made Vagrant, Packer, Consul, Vault and Nomad, and sold paid versions of them to large companies.

Vagrant was a side project for three years

Hashimoto later wrote that he started building Vagrant, a tool for setting up development environments, “in my college dorm room in 2010”.

On 27 November 2012, he announced HashiCorp “to drive Vagrant’s development forward”. Vagrant had been “a side project for me, receiving 2-4 hours a day when I had free time.” He planned “multiple sources of revenue: support, training, services, and paid add-ons”, and promised that “Vagrant will always remain open source and liberally licensed.” Armon Dadgar, who joined as cofounder in 2013, recalled in 2024 that Hashimoto “had built sort of a consulting lifestyle business around Vagrant.”

The first paid add-on shipped on 14 March 2013: a plugin that let Vagrant run VMware Fusion machines, at $79 per seat.

True Ventures funded HashiCorp first

True Ventures wrote that it met Hashimoto and Dadgar at Kiip, a startup it had backed. Hashimoto “was the first engineering hire at the company and worked from the True Ventures San Francisco office.” True “stayed close to him as he moved his focus to further building Vagrant and developing a company around it,” and seed funded HashiCorp in April 2013 “as the first investors in the company.” VentureBeat put HashiCorp’s funding before its Series A at $700,000.

Terraform’s launch day is still its biggest on GitHub

Hashimoto made the first commit to the Terraform repository on 21 May 2014. Terraform was announced on 28 July 2014, and the Hacker News post drew 600 points and 110 comments. GitHub dates 447 surviving stars (stars not since removed) to that day. Twelve years later, no day has passed it.

GitHub star history for hashicorp/terraform, 24 July to 2 August 2014, collected on 5 November 2026. Removed stars are not counted.

Mayfield and GGV backed the team and its open-source following

On 10 December 2014, HashiCorp announced a $10 million Series A led by Mayfield, with GGV Capital and True Ventures. The release said the money would “build out its enterprise offering, rapidly scale the team, and continue to support its existing millions of users.” Robin Vasan of Mayfield said the firm “had been in touch with Mitchell for over a year prior to investing”, and that it was “impressed with the team, the momentum of their open source projects, and the big opportunity in hybrid datacenter automation.” He compared the company to VMware.

Glenn Solomon of GGV gave his reasons on his blog. He described the founders as “two of the most incredible engineers with whom we’ve had the chance to work”, and wrote that “they’ve successfully recruited other exceptional engineers who’ve been contributors to their open source projects to join HashiCorp.” He counted more than 500,000 active users of HashiCorp’s tools, and wrote that they were “eager to learn more about HashiCorp’s commercialization activities.”

The same day, HashiCorp launched Atlas, a closed-source hosted service that ran its tools together. Hashimoto told VentureBeat: “We raised this money in order to bolster our hiring in order to sell Atlas.” The repository had 1,540 surviving stars dated before the round, and December 2014 brought 96.

Atlas was split into enterprise versions of each tool

Atlas did not become the business. Dadgar later called it “ill fated”, a platform “that we subsequently killed in 2016”, and said elsewhere that it was “misaligned to our target customer”. HashiCorp’s own account is that it took Atlas apart. In December 2017, it described “the path we began 18 months ago to split Atlas into a suite of smaller, module enterprise offerings to mirror the open source suite of tools.” Vault, Consul and Nomad left Atlas early in 2017, Atlas was renamed Terraform Enterprise, and HashiCorp scheduled its remaining Packer features to shut down on 31 May 2018.

Hashimoto stepped down as CEO in 2016, and Dave McJannet, an executive from GitHub and Hortonworks, took over.

Later rounds followed enterprise customers

The next rounds followed the enterprise versions. On 7 September 2016, HashiCorp raised a $24 million Series B led by GGV, with Redpoint joining. Dadgar described “the corresponding Enterprise applications we are building to solve the workflow challenges around the open source tools,” and the company named Condé Nast, Cisco and Mozilla as paying enterprise users. Solomon said “the adoption of these tools in global enterprises has been tremendous.”

HashiCorp’s review of 2017 recalled the doubt: “The big question for HashiCorp as we started 2017 was: can HashiCorp the company be successful? We knew the open source projects were successful, and we had grown a limited customer base in 2016.” By the end of that year, it wrote, the paid versions of Vault, Consul and Nomad, and Terraform Enterprise, had all become generally available. In October 2017, it raised a $40 million Series C led by GGV and Redpoint. McJannet said: “We were in a position where we didn’t need to raise funds but looked at it and thought that we want to make sure we make our customers successful.”

IVP led a $100 million Series D in November 2018, at a $1.9 billion valuation, and gave customers as one reason: “We conducted numerous customer reference calls and heard the same refrain: co-founders and CTOs Mitchell Hashimoto and Armon Dadgar, and CEO Dave McJannet, spend time with their customers and incorporate their feedback.” It also cited open-source adoption: 45 million downloads in a year, and about as many GitHub contributors to Terraform as to Apache Spark or Git. In March 2020, a $175 million Series E from Franklin Templeton valued the company at $5.1 billion.

Each year is a fiscal year ending 31 January, and customers are counted at its end. Figures are from HashiCorp’s S-1.

The IPO filing described a HashiCorp-controlled approach

HashiCorp went public on 9 December 2021 at $80 a share. Its filing said that “nearly all of our paid product adoption began with open-source usage”, and that customers paying $100,000 or more a year brought in 83% of revenue in fiscal 2021. It also described who controlled the code. Changes to an open-source project usually arrive as pull requests, proposed edits that the project’s maintainers review and merge:

“We have a HashiCorp-controlled approach to our open-source model. We designed our open-source workflow to encourage practitioners and partners to contribute to projects, but unlike third-party controlled open-source projects, we maintain control over our code base. Our open-source license … allows anyone to suggest code contributions that are reviewed by a HashiCorp-employed core committer before integration with our code base. In addition, all contributors are required to sign a contributor license agreement that grants HashiCorp exclusive license to distribute any accepted contribution commercially.”

The repository shows how much of the code came from HashiCorp itself. In the year before the license change, from 10 August 2022, 130 people had a pull request merged into Terraform’s core repository. At least 42 of them worked at HashiCorp at the time, by their commit email, their GitHub profile, or a public record of their role, and they wrote at least 415 of the 510 merged pull requests (81%). The 11 people with five or more merged pull requests all worked there; they alone wrote 353. An analysis by CHAOSS, a Linux Foundation project that measures the health of open-source communities, counted commits instead and found the same pattern over the same year: among people with at least five commits, those it identified as HashiCorp employees made 82% of the commits and 93% of the added lines.

This covers the core repository only. In June 2017, HashiCorp moved the providers, the plugins that connect Terraform to each cloud service, into separate repositories. The number of people with a merged pull request in the core repository fell from 530 in 2017 to 129 in 2018. Outside contributors could work on providers instead, which this count does not include.

HashiCorp moved Terraform to a source-available license

On 10 August 2023, HashiCorp announced that future releases of its products would use the Business Source License instead of the Mozilla Public License. The Business Source License still lets anyone read, copy and modify the code, but HashiCorp wrote that “vendors who provide competitive services built on our community products will no longer be able to incorporate future releases.” APIs, SDKs and “almost all other libraries” stayed under the Mozilla license, as did providers such as the AWS provider. HashiCorp gave its reason: “there are other vendors who take advantage of pure OSS models, and the community work on OSS projects, for their own commercial goals, without providing material contributions back.” The Hacker News thread drew 632 points and 731 comments.

Terraform’s stars barely moved that day: 17 are dated 10 August. The jump came later in the month, on 28 to 31 August (39, 34, 79 and 45 stars), after the fork had been announced.

OpenTofu was staffed by the companies that forked it

A fork is a copy of a project’s code that another group develops separately. On 15 August, companies that sold services built on Terraform published the OpenTF manifesto, asking HashiCorp to reverse the change. Ten days later, they announced a fork. It joined the Linux Foundation under the name OpenTofu on 20 September 2023. Harness, Spacelift and env0 each pledged the cost of five full-time engineers for at least five years, Scalr the cost of three, and Gruntwork the cost of one.

The fork’s repository opened to the public on 5 September 2023, when 2,178 surviving stars are dated. September 2023 brought 12,757, more than Terraform has gained in any full year.

The engineers came from those companies. Of the pull requests opened before the public launch and later merged, 98 of 105 came from people at Spacelift, env0 and Scalr, and none from the 130 people who had a pull request merged into Terraform the year before.

Across OpenTofu’s history, people we could tie to a company that employs or sponsors them, through OpenTofu’s steering committee list, company posts, commit emails or their own profiles, wrote between 73% and 79% of the 2,211 merged pull requests. The range depends on whether Christian Mesh, OpenTofu’s technical lead, is counted under Spacelift before September 2024, the earliest date we found for that link.

Spacelift’s share is between 43% and 49%, including 19% from Martin Atkins, who joined it from HashiCorp in 2024.

Stars are surviving stars dated to each year. Authors are people with at least one pull request merged that year, excluding bots and a Terraform release account. 2026 runs to collection on 5 November.

OpenTofu’s stars fell from 16,028 in 2023 to under 4,000 a year from 2025, while each repository kept a small group of authors, fewer than 100 a year since 2024.

One Terraform core engineer moved, 14 months later

Of the 130 people with a Terraform pull request merged in the year before the license change, one has since had a pull request merged into OpenTofu: Martin Atkins, a longtime Terraform core engineer at HashiCorp. His last Terraform pull request was merged on 9 September 2024. On 30 September, Spacelift wrote that he had joined its OpenTofu team and “will focus exclusively on OpenTofu.” His first OpenTofu pull request is dated 2 October 2024. He wrote 30% of OpenTofu’s merged pull requests in 2025 and 31% in 2026, more than anyone else.

That only one person moved is less telling than it looks. Most of the work came from HashiCorp employees, and outside contributors rarely return even to Terraform: of the 88 people in that year’s group we could not tie to HashiCorp, 7 have had another pull request merged since. Across all 130 the figure is 30, in line with the 20% to 25% of each calendar year’s group from 2018 to 2023.

IBM agreed to buy HashiCorp eight months after the change

Hashimoto left HashiCorp in December 2023. On 24 April 2024, IBM agreed to buy the company for $35 a share, an enterprise value of $6.4 billion, and the deal closed on 27 February 2025.

HashiCorp’s growth had slowed before then. In the year to January 2024, revenue grew 23% to $583.1 million, and net dollar retention, a measure of how much more existing customers spent, fell from 131% to 115%. HashiCorp’s filings do not tie the slowdown to the license change.

What a small team can take from HashiCorp

These are our inferences from the record above, not claims by HashiCorp or its investors.

Both early lead investors knew Hashimoto well before they invested. True Ventures had known him since Kiip, before HashiCorp existed, and Mayfield had been in touch with him for more than a year before the Series A.

The product the Series A was raised to sell did not become the business. Hashimoto said the money was to sell Atlas, a single hosted platform. The business came from splitting it into enterprise versions of each open-source tool, and what remained of Atlas became Terraform Enterprise. Later investors cited enterprise customers alongside open-source adoption.

Owning the code base was part of the business model, and the filing said so. In the year before the change, HashiCorp’s engineers wrote most of the core code and reviewed the rest, and every contributor signed over commercial rights. That made the license change possible. It also meant a fork started with the code but none of the people who wrote it. The companies behind OpenTofu supplied their own engineers, and 14 months passed before one of Terraform’s core engineers joined them.

Stars and authorship told different stories. OpenTofu gained more stars in its first month than Terraform gains in a year, but the work still came from a few dozen paid engineers, as it had at Terraform.

Sources and method

This article covers 2010–2026. Star figures come from GitHub’s repository star history API, collected on 4 and 5 November 2026. It returns stars still present (“surviving stars”), not historical displayed totals or users: Terraform’s 661 weeks sum to its 50,146 stars at collection, and OpenTofu’s 169 weeks to its 30,723. Daily, monthly and yearly groupings use the returned week timestamps and day offsets; GitHub’s documentation says week and day boundaries are not guaranteed to align with UTC.

Pull request figures cover all 17,135 pull requests in hashicorp/terraform and 2,749 in opentofu/opentofu, retrieved through GitHub’s GraphQL API on 4 and 5 November 2026. We excluded pull requests opened by GitHub app accounts, by deleted accounts, by the hashibot-web bot and by hc-github-team-tf-core, a release account. A person counts as having a merged pull request in a year if one of theirs was merged that year. Provider repositories are not included.

We counted someone as working at HashiCorp if their commits on these pull requests used a hashicorp.com email, their GitHub profile named HashiCorp, they were a public member of the hashicorp organisation, or a public record such as a HashiCorp blog author page, a résumé, LinkedIn or a forum signature gave the role. Profile and organisation signals reflect November 2026, and we excluded profiles describing former employment or outside contribution. For OpenTofu, we used the steering committee list in its contributing guide, Spacelift’s posts, company email domains and contributors’ own profiles, and counted each person under a company only within the dates we found. People we could not identify are not counted for any company, so all employer shares are lower bounds.

Hacker News points and comments come from the Algolia Hacker News API in November 2026. Funding dates are announcement dates. Financial figures are from HashiCorp’s SEC filings and IBM’s announcements.