# Companies using RTEMS

638 companies use RTEMS, based on their job posts and their employees' public profiles. Its share of job posts held steady in the three months to August 2026; 266 job posts named it from October 2025 to August 2026. Embedded Engineer is the role that names it most often.

Data as of November 9, 2026. Source: Sumble.

## Which companies name RTEMS in the most job posts?

The companies with the most job posts naming RTEMS are D-Orbit (50), TMC (43) and Viveris (40). Altran is the newest of the five companies in the table, with its first job post naming it in January 2026.

| Company | Job posts | People | Recent job post |
|---|---:|---:|---|
| [D-Orbit](https://sumble.com/orgs/d-orbit) | 50 | 3 | "Knowledge of real-time operating systems (such as RTEMS or FreeRTOS) and/or operating systems targeted for embedded applications (such as any embedded Linux)" (Senior Flight Software Engineer, Nov 3, 2026) |
| [TMC](https://sumble.com/orgs/tmc-c168b236) | 43 | 1 | "…in any language from the C family Knowledge of real-time operating systems (such as RTEMS or FreeRTOS) and/or operating systems designed for embedded applications (such as any embedded Linux)…" (Embedded Software Engineer - Aerospace, Apr 22, 2026) |
| [Viveris](https://sumble.com/orgs/viveris) | 40 | 0 | " Expérience en développement temps réel avec OS type VxWorks, RTEMS, RTOS" (real-time embedded software engineer - space m/f, Aug 7, 2025) |
| [Altran](https://sumble.com/orgs/capgemini-engineering) | 36 | 3 | "Linux temps réel (PREEMPT_RT), VxWorks, PikeOS, RTEMS, FreeRTOS" (low-level embedded software architect, Oct 24, 2026) |
| [Los Alamos National Laboratory](https://sumble.com/orgs/los-alamos-national-laboratory) | 30 | 2 | "Real-time system programming experience with VxWorks or RTEMS." (Low-Level Radio Frequency Engineer (R&D Engineer 2/3), Sep 13, 2026) |

## Is hiring for RTEMS growing?

RTEMS holds a steady place in hiring. 0.16 in every 10,000 job posts named it from June to August 2026, against 0.16 from March to May. From October to December 2025 it was 0.10.

| Month | Job posts naming it | All job posts | Per 10,000 job posts |
|---|---:|---:|---:|
| Oct 2025 | 16 | 1,413,673 | 0.11 |
| Nov 2025 | 18 | 1,822,119 | 0.10 |
| Dec 2025 | 10 | 1,236,103 | 0.08 |
| Jan 2026 | 25 | 1,828,002 | 0.14 |
| Feb 2026 | 18 | 1,856,647 | 0.10 |
| Mar 2026 | 29 | 1,850,711 | 0.16 |
| Apr 2026 | 24 | 1,728,886 | 0.14 |
| May 2026 | 35 | 1,821,509 | 0.19 |
| Jun 2026 | 38 | 1,909,496 | 0.20 |
| Jul 2026 | 21 | 1,815,180 | 0.12 |
| Aug 2026 | 32 | 1,835,698 | 0.17 |

## How many companies named RTEMS in a job post for the first time in recent months?

Job posts named RTEMS for the first time at 16 companies from June to August 2026, against 20 from March to May. The 16 from June to August are 5.8% of all 278 companies whose job posts name it.

| Period | Companies naming it in a job post for the first time |
|---|---:|
| March to May 2026 | 20 |
| June to August 2026 | 16 |
| October 2025 to August 2026 | 68 |

Companies whose first job post naming it appeared in that period. Recruiters, staffing firms and job boards are left out.

## How do we know which companies use RTEMS?

278 of the 638 companies name RTEMS in their own job posts. The other 360 show up because employees list it on their profiles. 45 show up in both job posts and employees' profiles.

| How we know | Companies | Share |
|---|---:|---:|
| Job posts name RTEMS | 278 | 44% |
| Employees' profiles list RTEMS | 360 | 56% |

## What size are the companies that use RTEMS?

No size of company stands out for RTEMS. Companies with 50 to 999 employees make up the largest group, at 40%. The second-largest group is companies with more than 5,000 employees, at 23%.

| Size | Share | Typical tech page |
|---|---:|---:|
| Under 50 employees | 22% | 22% |
| 50 to 999 | 40% | 38% |
| 1,000 to 5,000 | 15% | 17% |
| Over 5,000 | 23% | 23% |

## Where are RTEMS companies based?

RTEMS has an unusually large following in Italy: 4.8% of its companies, against 1.5% on the typical tech page. France is second, at 8.7%.

| Country | Companies | Share | Typical tech page |
|---|---:|---:|---:|
| United States | 236 | 39% | 43% |
| France | 53 | 8.7% | 4.6% |
| Germany | 42 | 6.9% | 4.4% |
| Spain | 34 | 5.6% | 1.8% |
| Italy | 29 | 4.8% | 1.5% |
| Switzerland | 23 | 3.8% | 1.5% |

## Which teams work with RTEMS?

RTEMS turns up most in job posts for engineering, embedded software and flight software teams. Engineering division and orion program teams follow, at 3 companies each.

| Team | Companies |
|---|---:|
| Engineering | 5 |
| Embedded software | 4 |
| Flight software | 4 |
| Engineering division | 3 |
| Orion program | 3 |
| Avionics | 2 |

## Which roles mention RTEMS most?

Embedded Engineer is the most common role, in 32% of job posts naming RTEMS. The top four roles cover 72% of these job posts.

| Role | Share | Oct 2025 to Aug 2026 | Mar to May 2026 | Jun to Aug 2026 |
|---|---:|---:|---:|---:|
| Embedded Engineer | 32% | 85 | 27 | 30 |
| Software Engineer | 20% | 54 | 14 | 18 |
| Aerospace Engineer | 11% | 30 | 11 | 12 |
| Firmware Engineer | 8.3% | 22 | 7 | 3 |
| Electrical Engineer | 1.9% | 5 | 3 | 1 |
| Control Engineer | 1.5% | 4 | 2 | 2 |

## Which companies started naming RTEMS in job posts recently?

Between April and August 2026, RTEMS appeared for the first time in job posts at 19 companies: 13 commercial, 5 mid-market and 1 enterprise. Command Post Technologies, Inc has the most job posts of the new commercial companies, 5 from April to August.

| Group | Company | Job posts, April to August 2026 |
|---|---|---:|
| Commercial | [Command Post Technologies, Inc](https://sumble.com/orgs/command-post-technologies) | 5 |
| Commercial | [SSC - Swedish Space Corporation](https://sumble.com/orgs/swedish-space) | 3 |
| Commercial | [ADENTIS Italia](https://sumble.com/orgs/adentis-italia) | 3 |
| Commercial | [Azista Space](https://sumble.com/orgs/azista-bst-aerospace) | 2 |
| Commercial | [OVERTECH Consulting](https://sumble.com/orgs/overtech-consulting) | 2 |
| Mid-market | [Sener](https://sumble.com/orgs/sener) | 2 |
| Mid-market | [Scalian](https://sumble.com/orgs/scalian) | 1 |
| Mid-market | [agap2](https://sumble.com/orgs/agap2) | 1 |
| Mid-market | [UICGS / Bowhead Family of Companies](https://sumble.com/orgs/bowhead) | 1 |
| Mid-market | [Vast](https://sumble.com/orgs/vastspace) | 1 |

Companies that named RTEMS in a job post for the first time between April and August 2026, ranked by their job posts in those months. AI-native companies get a group of their own, whatever their size. Recruiters and job boards are left out.

## What else do RTEMS companies use?

RTEMS companies are 811 times as likely as similar companies to use SpaceWire: 39% of them, against 0.05%. Next is VxWorks: 62% of these companies use it, against 0.21% of similar ones.

| Tool | Companies | Also name it | Typical | Times as common |
|---|---:|---:|---:|---:|
| SpaceWire | 70 | 39% | 0.05% | 811 times |
| VxWorks | 113 | 62% | 0.21% | 294 times |
| Microsemi | 15 | 8.3% | 0.03% | 292 times |
| SPARC | 18 | 9.9% | 0.04% | 265 times |
| NX Nastran | 16 | 8.8% | 0.04% | 247 times |
| Libero | 16 | 8.8% | 0.04% | 229 times |
| RS422 | 64 | 35% | 0.16% | 219 times |
| FEMAP | 50 | 28% | 0.14% | 194 times |

Shares are out of the 181 companies whose job posts name RTEMS, not counting firms whose job posts name almost every technology.

## About this data

Sumble built this page. Sumble gives sales, marketing and other GTM teams technographics and hiring signals for the companies they sell to: the technologies each company uses, which teams are hiring and for what, and who reports to whom. That helps a team know who to contact, why now, and what to say.

Sumble covers more than 3.6 million companies, 93 million job posts collected since 2022 and 194 million employee profiles, and tracks more than 37,000 technologies. It finds which technologies a company uses by reading its job posts and its employees' public profiles.

Sumble has a free plan, and the same data is available through its API and MCP server.

A company counts when its own job posts or its employees' public profiles name the technology. Hiring is that technology's share of all job posts collected each month. Quotes are copied word for word from the companies' job posts.

Every figure on this page comes from Sumble's own analysis, and you won't find it outside Sumble.