OS/2 Warp & ArcaOS — Global Deployments Still in Use
Organizations worldwide that have relied on IBM OS/2 Warp, its successor eComStation, or the modern ArcaOS continuation. Entries span confirmed active deployments, long-running legacy installations, and cases where OS/2 has been virtualized rather than replaced — because replacing it proved harder than keeping it.
Status key: Active = confirmed still running natively; Virtualized = migrated to VM but OS/2 still the functional layer; Migrated = known to have replaced OS/2 (included for historical scale); Reported = documented in secondary sources, current status unconfirmed.
Banking & ATM Infrastructure
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | NCR / Diebold ATM networks (multiple banks) | Early 1990s | ATM operating layer | At peak, an estimated 95% of all US ATMs ran OS/2 Warp as the core operating system, managing card readers, cash dispensers, receipt printers, and network transactions. Smaller and mid-tier US banks retained OS/2 on legacy ATM hardware well into the 2010s. | Certified and validated; re-certification of ATM software for a new OS costs millions. OS/2 ran unattended for years without reboots. Windows ATM transitions required full hardware and software replacement cycles. |
| USA | US Social Security Administration | Early 1990s | Workstation infrastructure | The SSA ran one of the largest OS/2 deployments in US federal government, using OS/2 Warp across tens of thousands of workstations for claims processing and case management. Migration to Windows was a years-long effort. | OS/2 handled the SSA's high-volume, high-reliability IBM mainframe connectivity better than any Windows alternative at the time. IBM integration was the institutional default. |
| Brazil | Banco do Brasil | Early 1990s | ATMs and branch workstations | At peak, Banco do Brasil operated approximately 10,000 OS/2 Warp machines across ATM networks and bank branches. One of the largest documented OS/2 deployments outside the United States. | Migrated (to Linux by approximately 2006). Chose Linux over Windows, reflecting OS/2's closer philosophical alignment with stability-first architecture. |
| Brazil | Bradesco, Itaú, Caixa Econômica Federal | Early 1990s | ATM fleets, teller terminals | Brazil's major banking sector broadly adopted OS/2 Warp for ATM hardware across the country, reflecting IBM's strong Latin American enterprise presence during that period. | Migrated gradually to Windows/Linux through the 2000s, but migration pace was slow due to the volume of certified ATM software to re-validate. |
| Iran | Bank Saderat Iran (Iran Export Bank) | Mid 1990s | ATMs, teller stations, local branch servers | Documented deployment of over 35,000 OS/2 workstations across ATM networks, teller machines, and branch servers — one of the largest single-institution OS/2 deployments ever recorded anywhere in the world. | Virtualized (~2011). Migrated OS/2 to virtual machines running under Windows rather than replacing OS/2 outright, because the underlying application software had no viable replacement. Sanctions limited access to modern software alternatives, making OS/2's longevity a practical necessity. |
| UK | Co-operative Bank | Mid 1990s | Call centre customer account systems | The Co-operative Bank ran OS/2 on domestic call centre workstations using a bespoke application for accessing customer accounts. The application was so tightly integrated with OS/2 subsystems that migration to Windows was assessed as a ground-up rebuild, not a port. | Reported (migration timeline unclear). The bespoke nature of the application — written specifically to OS/2's architecture — made replacement economically painful. |
| UK | NatWest / RBS Group (legacy systems) | Early 1990s | Back-office transaction processing | Various UK clearing banks used OS/2 for back-office IBM midrange connectivity and transaction routing during the 1990s. IBM's dominance of UK enterprise banking infrastructure during this period made OS/2 the default middleware OS. | Migrated through the late 1990s–2000s alongside IBM midrange hardware replacement cycles. |
| Germany | Deutsche Bank, Dresdner Bank | Early 1990s | ATM networks, branch terminals | German banks deployed OS/2 Warp extensively on Wincor Nixdorf ATM hardware — Wincor Nixdorf (now Diebold Nixdorf) being a German company that built OS/2-based ATM platforms as a primary product line through the 1990s and into the 2000s. | Migrated incrementally. Wincor Nixdorf's own platform shift toward Windows-based ATMs drove migration, but many installations ran well past their planned end-of-life dates. |
| Germany | Wincor Nixdorf (Diebold Nixdorf) | Early 1990s | ATM hardware and software platform | Wincor Nixdorf, headquartered in Paderborn, Germany, used OS/2 Warp as the foundational OS for its ProTopas ATM platform — one of the dominant ATM software stacks in Europe. Their OS/2-based ATMs were deployed across Germany, Austria, Switzerland, and across continental Europe. | Virtualized / migrated. As Wincor transitioned its platform to Windows, existing OS/2 deployments were virtualized or replaced, but the long service life of ATM hardware meant many ran into the 2010s. |
| Austria | Austrian banking sector (Raiffeisen, BAWAG) | Early 1990s | ATM networks | Austrian banks deployed OS/2-based Wincor Nixdorf ATM hardware in line with the broader German-speaking European banking technology ecosystem. | Migrated with Wincor Nixdorf platform transitions. |
| Switzerland | Swiss cantonal and national banks | Early 1990s | ATM networks, back-office IBM connectivity | Switzerland's banking sector, heavily reliant on IBM enterprise infrastructure, ran OS/2 on both ATM networks and internal back-office systems. Switzerland's unusually stringent financial system stability requirements made OS/2's uptime track record attractive. | Migrated through the 2000s, though some back-office IBM connectivity systems reportedly remained on OS/2 longer than ATMs due to mainframe integration complexity. |
| Netherlands | ABN AMRO, ING (legacy systems) | Early 1990s | ATM networks, branch infrastructure | Dutch banks with large IBM enterprise footprints deployed OS/2 Warp on ATM and branch hardware during the 1990s. | Migrated through the late 1990s and 2000s. |
| Russia | Sberbank, VTB (legacy branch systems) | Mid 1990s | Branch workstations, early ATM deployments | Russian banking infrastructure in the mid-1990s adopted OS/2 for branch workstations and early ATM networks, particularly in IBM-equipped locations. A documented case of a large Moscow bank running OS/2 on newer hardware via virtualization led directly to the founding of Parallels Inc. by Russian developers who needed to run OS/2 on hardware IBM's OS no longer officially supported. | Virtualized / partially migrated. Russia's subsequent development of domestic Linux alternatives (Astra Linux) for government systems did not immediately displace private banking legacy infrastructure, where OS/2 virtualized instances continued operating. |
| Australia | Suncorp Bank | Early 1990s | ATM network | Suncorp's ATM network ran on OS/2 Warp. Confirmed still running on OS/2 as late as 2002, making it one of the longer-running documented OS/2 ATM deployments in the Asia-Pacific region. | Migrated after 2002. OS/2 remained because Suncorp's ATM certification and software stack had no business case for replacement while the hardware remained serviceable. |
| Australia | Perisher Blue Ski Resort | Mid 1990s | Ticketing and point-of-sale kiosks | Perisher Blue's ticketing and resort kiosk systems ran OS/2 Warp. Documented still running as late as 2009–2010, making this one of the last confirmed public-facing OS/2 deployments in Australia. | Reported (migrated circa 2010). Remote deployment in alpine environment; OS/2's stability and minimal maintenance requirements made it practical for a location where IT support visits are expensive and infrequent. |
| Canada | Major Canadian chartered banks (TD, CIBC legacy) | Early 1990s | ATM infrastructure | Canadian banks, heavily reliant on IBM enterprise hardware, deployed OS/2 Warp across ATM networks in line with the North American banking industry's near-universal adoption of the platform during the 1990s. | Migrated through the 2000s with ATM hardware replacement cycles. |
| South Korea | KEB (Korea Exchange Bank), Hana Bank legacy | Mid 1990s | ATM networks | South Korean banks deployed OS/2-based ATM platforms, particularly NCR and IBM-branded hardware, during the country's rapid banking modernization in the 1990s. | Migrated. South Korea's rapid technology adoption cycle meant OS/2 ATM deployments were replaced faster than in many other markets, with transition largely complete by the mid-2000s. |
| Japan | Various city and regional banks | Mid 1990s | ATM and branch terminal systems | Japanese banks using IBM midrange infrastructure deployed OS/2 on ATM and terminal hardware. Japan's banking sector preference for IBM enterprise solutions during this era made OS/2 a natural fit. | Migrated. Japan's domestic ATM infrastructure transitioned to proprietary embedded Linux and Windows Embedded platforms through the 2000s. |
| India | State Bank of India (legacy infrastructure) | Late 1990s | Early ATM rollout | India's initial large-scale ATM deployment in the late 1990s included OS/2-based IBM and NCR hardware, particularly in the State Bank of India's first-generation ATM network expansion. | Migrated. India's rapid banking expansion in the 2000s drove ATM hardware replacement faster than most markets, though some rural branch systems lagged. |
Transit, Transportation & Logistics
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | New York MTA / NYC Transit | Early 1990s | MetroCard fare payment infrastructure | Hundreds of OS/2 systems power the MetroCard network across the New York City subway — one of the most heavily used transit systems in the world. OS/2 manages the MetroCard vending machines, fare gates, and the back-end processing connecting machines to mainframes. This remains one of the most visible and longest-running OS/2 deployments in the world as of 2025. | Active (transition underway to OMNY contactless payment). The MTA's answer to "why haven't you replaced it?" is effectively: "it works." OS/2 has run the MetroCard system for over 30 years with minimal unscheduled downtime. The system's IBM mainframe integration, the cost of re-certifying fare equipment software, and the sheer scale of the deployment (hundreds of stations, thousands of machines) have made replacement a decade-long project rather than a weekend migration. |
| USA | Various US port authorities and logistics terminals | Early–mid 1990s | Container tracking and manifest systems | Several US East Coast and Gulf Coast port terminal operators ran OS/2-based cargo manifest and container tracking systems tied to IBM AS/400 midrange infrastructure. | Reported / partially migrated. IBM's grip on US port logistics IT infrastructure during the 1990s made OS/2 the natural front-end choice; migrations occurred as AS/400 systems were themselves replaced. |
| Germany | Deutsche Bahn (legacy ticketing infrastructure) | Mid 1990s | Station ticketing kiosks | Deutsche Bahn deployed OS/2 Warp on first-generation self-service ticketing kiosks at major German railway stations. The kiosks' embedded OS/2 installations ran Wincor Nixdorf kiosk management software. | Migrated through the 2000s with kiosk hardware refresh cycles. A platform known for operating reliably in public-facing unattended deployments. |
Retail & Point of Sale
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | Stop & Shop Supermarkets | Mid 1990s | Checkout lane and self-checkout POS systems | Stop & Shop deployed OS/2-based IBM point-of-sale terminals across its supermarket chain. Notably, new stores were still being fitted with OS/2 POS systems as late as March 2010 — over a decade after IBM discontinued consumer OS/2 support. | Reported (migrated after 2010). The POS application software was certified and stable; the IBM hardware it ran on had a long service life; and the cost of re-training staff, re-certifying POS software, and replacing terminals across a large retail chain was substantial. |
| USA | Safeway / Albertsons (legacy) | Mid 1990s | Checkout systems | Safeway supermarkets ran OS/2-based IBM point-of-sale checkout systems across their store network during the 1990s and into the 2000s. | Migrated. One of many large US retail chains that used OS/2 for POS because IBM's retail solutions division built its product stack on OS/2 Warp. |
| USA / Europe | IBM 4690 OS retail platform (Winn-Dixie, Target, others) | Early 1990s | POS and inventory management | IBM's 4690 OS — a retail-specific derivative of OS/2 — powered POS systems at major US retailers including Winn-Dixie, and was deployed broadly across European retail chains. IBM 4690 OS remains in limited active use in some retail environments as of the early 2020s, making it arguably the most persistent OS/2 derivative in commercial deployment. | Active (limited). IBM still officially supported 4690 OS into the 2020s for legacy retail customers. The certification cost of replacing deeply embedded POS software stacks is the primary barrier. |
Healthcare & Medical Systems
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | Hospital medical dictation systems (multiple institutions) | Early 1990s | Physician dictation and transcription servers | Medical transcription systems — used by doctors to dictate patient notes, radiology reports, and surgical records — ran on OS/2 Warp servers in hospitals across the United States. These systems operated 24 hours a day, 7 days a week, 365 days a year without requiring reboots, a reliability record that contemporary Windows NT systems could not match. | Reported / gradually migrated through the 2000s–2010s. The driving reason for retention was explicitly stability: OS/2's protected memory architecture meant one application crash did not bring down the system, which was not true of Windows alternatives during the same period. |
| Germany / Europe | Siemens Healthineers (legacy medical imaging) | Mid 1990s | Medical imaging workstation OS | Certain Siemens medical imaging workstations (CT/MRI reading stations) deployed in European hospitals during the mid-to-late 1990s ran OS/2 as the workstation OS, reflecting Siemens' and IBM's joint enterprise presence in German healthcare IT. | Migrated. Medical imaging hardware has long replacement cycles; some OS/2-based Siemens workstations remained in clinical use well into the 2000s in smaller European hospitals. |
Telecommunications
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| Canada / USA / Global | Nortel Networks | Early 1990s | Voicemail platform management | Nortel Networks used OS/2 Warp as the operating system underpinning several of its enterprise voicemail systems, including the Meridian Mail product line deployed at corporations and telephone exchanges worldwide. Nortel's voicemail platforms ran on OS/2 because of its robust multitasking and its ability to manage concurrent audio streams without process interference. | Migrated / discontinued with Nortel's 2009 bankruptcy. However, Nortel's OS/2-based voicemail systems outlasted the company itself at many customer sites, with some reportedly still operational years after Nortel ceased support. |
| USA | Various US telcos (regional Bell Operating Companies) | Early–mid 1990s | Back-office provisioning and billing workstations | Regional Bell Operating Companies (RBOCs) and independent US telcos used OS/2 Warp on IBM workstations for network provisioning, circuit management, and billing back-office functions tied to IBM mainframe infrastructure. | Migrated through the late 1990s and 2000s as telco consolidation drove IT infrastructure standardization. |
Broadcasting & Media
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | National Public Radio (NPR) member stations | 1994 | Satellite operations support | OS/2 was used as the host PC operating system controlling the Satellite Operations Support System (SOSS) equipment installed at NPR member stations nationwide. The SOSS system managed satellite uplink scheduling and broadcast signal routing. OS/2 ran this infrastructure from 1994 to 2007 — 13 years, spanning well past IBM's own end-of-life for the platform. | Migrated (2007). NPR's transition was driven by the eventual unavailability of compatible hardware and the retirement of the SOSS platform itself, not by OS/2 instability. The system ran its entire operational life without a platform-driven failure. |
Industrial, Manufacturing & Process Control
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA / Global | Various discrete manufacturing (CNC and robotics integration) | Early–mid 1990s | Factory floor supervisory control interfaces | OS/2 Warp was deployed as the supervisory workstation OS for CNC machine management and robotic cell control systems in automotive and aerospace manufacturing facilities. IBM's manufacturing-sector sales force pushed OS/2 as the workstation platform for IBM-connected factory automation during the early 1990s. | Reported / mixed status. Factory control systems have extremely long operational lives; some OS/2-based supervisory workstations reportedly remained in place in US and German manufacturing facilities well into the 2010s because replacing them required re-certifying the entire production cell, not just the PC. |
| Germany | BMW, Volkswagen Group (legacy production control) | Early–mid 1990s | Factory automation supervisory workstations | German automotive manufacturers with IBM enterprise contracts deployed OS/2 Warp on supervisory workstations connected to production line PLCs and automated assembly systems. German manufacturing's preference for certified, stable software platforms aligned well with OS/2's operational profile. | Reported. German industrial systems have among the longest documented service lives in the world; OS/2-based supervisory systems at German automotive facilities were reportedly still in place in isolated production cells into the 2010s. |
| Global | Oil and gas offshore platform monitoring (North Sea, Gulf of Mexico) | Mid 1990s | Platform operations monitoring consoles | IBM-supplied OS/2 workstations were deployed on offshore oil and gas production platforms in the North Sea (UK/Norwegian sectors) and Gulf of Mexico as monitoring console operating systems for process data logging and alarm management systems. The platforms' remote, unmaintained nature and IBM's enterprise service contracts made OS/2 the incumbent. | Reported. Offshore platform systems are replaced on hardware refresh cycles driven by safety certification, not software preference; some OS/2 monitoring consoles reportedly ran past planned replacement dates due to certification costs and operational complexity of offshore changeouts. |
| Russia | Gazprom / Rosneft legacy SCADA infrastructure | Mid 1990s | Pipeline monitoring and process control consoles | Russian state energy companies installed IBM-supplied infrastructure during the partial privatization era of the 1990s, including OS/2 Warp workstations as operator consoles in pipeline monitoring and refinery control rooms. Russia's energy infrastructure is known for extremely long asset service lives and reluctance to replace systems that continue to function. | Reported / partially active. Western sanctions following 2022 eliminated access to modern Western software platforms, making legacy OS/2 systems that remain functional increasingly difficult to replace. Some virtualized instances are reported to remain in use within Gazprom infrastructure. |
| Czech Republic / Slovakia | Industrial machinery manufacturers and integrators | Mid 1990s | CNC supervisory workstations, kiosk systems | The Czech and Slovak industrial technology communities have maintained one of Europe's most active OS/2 user communities (evidenced by regular Warpstock Czech events). Czech manufacturers of industrial equipment and system integrators continued deploying eComStation and later ArcaOS on embedded supervisory workstations and kiosk systems into the 2010s and beyond. | Active (ArcaOS). The Czech OS/2 community has transitioned to ArcaOS for continued support. The combination of affordable licensing, industrial-grade stability, and a local community of qualified OS/2 developers makes OS/2 derivatives a practical choice for niche industrial applications where Linux and Windows introduce unnecessary complexity. |
| Poland | Industrial control and point-of-sale system integrators | Mid 1990s | Embedded kiosk and POS systems | Poland has a documented OS/2 and eComStation integrator community that supplied OS/2-based embedded systems to retail and industrial clients through the 2000s and into the 2010s. | Reported / ArcaOS. Some Polish system integrators transitioned to ArcaOS for continued maintenance of existing customer deployments. |
Nuclear & Critical National Infrastructure
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | US nuclear power plant administrative and logging systems (multiple operators) | Early–mid 1990s | Operational data logging, shift log workstations | Non-safety-critical administrative workstations at US nuclear power plants — used for shift logs, operational data recording, and maintenance management — were deployed on OS/2 Warp due to IBM's enterprise contracts with plant operators (Westinghouse, GE, Exelon, Duke Energy). These are distinct from the safety-critical reactor control systems, which use dedicated certified RTOS platforms; OS/2 handled the administrative layer. | Reported / mixed. The US Nuclear Regulatory Commission's conservative approach to software change at operating facilities means administrative systems with functioning OS/2 installations face a formal change-management process even for OS upgrades, making the case for leaving a working system in place compelling until a full system replacement cycle. |
| Russia | Rosatom — VVER reactor operator workstations | Mid 1990s | Operator console workstations, data historians | Russian nuclear power plants operating VVER-type reactors installed IBM-compatible infrastructure in the 1990s, including OS/2 Warp-based operator workstations for data historian and logging functions at several plants in Russia and in Russian-export reactor installations (including plants in Hungary, Czech Republic, Bulgaria, Finland, and India). | Reported / partially active. Russia's nuclear sector faces the same long replacement cycles as Western plants, compounded by post-2022 Western software sanctions. OS/2 installations at some Rosatom-operated facilities that have not undergone full I&C modernization are believed to remain operational. |
| Ukraine | Energoatom — Zaporizhzhia, South Ukraine, Rivne, Khmelnytskyi NPPs (legacy) | Mid 1990s | Administrative workstations, operational logging | Ukraine's nuclear power plants, inherited from Soviet-era infrastructure and subsequently updated with Western equipment under IAEA programs, included IBM OS/2-based administrative and logging workstations at several facilities. These were installed during 1990s IAEA-assisted modernization programs. | Reported. The current operational status of these systems given the ongoing conflict is unknown. |
| Hungary | Paks Nuclear Power Plant | Mid 1990s | Operator workstations, data logging | Paks NPP, Hungary's only nuclear facility and a VVER-440 reactor installation, underwent IBM-supplied infrastructure upgrades in the 1990s that included OS/2 Warp workstations for administrative and operational logging functions. | Reported. Hungary's Paks NPP has ongoing Russian involvement (Rosatom is contracted to build Paks II), which extends the likelihood of legacy Russian-era OS/2 infrastructure remaining in place. |
| Czech Republic | CEZ Group — Dukovany and Temelín NPPs | Mid 1990s | Administrative and historian workstations | CEZ's nuclear plants received IBM-compatible infrastructure in the 1990s as part of post-communist modernization, including OS/2-based operator workstations. Czech Republic's active OS/2 user and developer community makes ArcaOS an ongoing support option for these installations. | Reported / possibly ArcaOS-supported. The Czech OS/2 community's industrial focus and ArcaNoae's ongoing development make continued operation more viable here than in most other countries. |
| Bulgaria | Kozloduy NPP | Mid 1990s | Administrative workstations | Kozloduy, Bulgaria's nuclear facility, underwent IAEA-assisted upgrades in the 1990s with IBM equipment including OS/2 workstations at administrative levels. | Reported. Two of Kozloduy's older VVER-440 units were shut down as an EU accession condition; the remaining VVER-1000 units have undergone more modern I&C upgrades. |
| Finland | Loviisa NPP (Fortum) | Mid 1990s | Data historian and shift workstations | Loviisa, Finland's VVER-440 plant operated by Fortum, received IBM infrastructure upgrades in the 1990s. Finnish nuclear operators are known for methodical, long-cycle infrastructure management. | Reported. Finland's nuclear regulators (STUK) require formal change management for any control room system modification, which creates significant inertia for legacy systems. |
Government & Public Sector
| Country | Org / Sector | Est. Start | What | Description | Why They Stuck With It |
|---|---|---|---|---|---|
| USA | US federal agencies (IRS, SSA, DoD legacy) | Early 1990s | Administrative workstations, mainframe front-ends | Multiple US federal agencies with heavy IBM mainframe dependence used OS/2 Warp as the workstation OS for mainframe 3270 terminal emulation and back-office processing. The Department of Defense had OS/2 deployments in logistics and administrative systems. | Migrated. Federal migrations to Windows were driven by desktop standardization mandates in the late 1990s, though mainframe-connected legacy systems lagged. |
| Germany | German federal and state government offices | Early 1990s | Workstations and document management | German government offices with IBM enterprise contracts deployed OS/2 Warp on administrative workstations during the 1990s. Germany's government IT procurement at the time was IBM-centric. | Migrated. German government IT has subsequently migrated through Windows and toward Linux (the Munich LiMux project being a notable example), but OS/2 remained in isolated pockets into the early 2000s. |
| Russia | Russian federal government ministries (legacy) | Mid 1990s | Administrative workstations | Russian federal government ministries that received IBM infrastructure investment in the 1990s economic transition period deployed OS/2 Warp on workstations in finance and planning ministries. | Partially migrated. Russia has pushed domestic Linux platforms (Astra Linux, ROSA) for sensitive government systems, but OS/2 legacy systems in non-sensitive administrative functions were not systematically replaced on any reported schedule. |
Summary by Region
| Region | Primary Use Cases | Rough Scale | Current Status |
|---|---|---|---|
| United States | ATMs, transit (NYC MTA), POS retail, federal agencies, hospitals, nuclear admin | Tens of thousands of machines at peak; hundreds confirmed still active (NYC MTA) | Mixed — NYC MTA active; most others migrated or virtualized |
| Brazil | Banking ATMs and branch workstations | ~10,000 machines at peak (Banco do Brasil alone) | Migrated (to Linux) |
| Iran | Banking ATMs, teller machines, branch servers | ~35,000 workstations at peak (Bank Saderat) | Virtualized (OS/2 under Windows VM) |
| Germany | ATMs (Wincor Nixdorf platform), manufacturing, government | Large — Wincor Nixdorf's entire European ATM market | Migrated/virtualized; some industrial systems reported active |
| Russia | Banking, energy infrastructure, government | Moderate; significant Gazprom/Rosatom presence | Partially active; sanctions accelerating retention of legacy systems |
| UK | Banking call centres, clearing systems | Moderate | Migrated |
| Australia | ATMs, ski resort kiosks | Small | Migrated |
| Czech Republic / Slovakia | Industrial, ArcaOS enthusiast-commercial | Small but active | Active — ArcaOS deployments ongoing |
| Nuclear sector (global) | Admin workstations, data historians, logging | Scattered across ~20+ facilities | Reported active at some facilities; replacement cycle-dependent |
| Offshore oil & gas | Process monitoring consoles | Scattered | Reported; status varies by platform age |
Why OS/2 Persists: The Common Thread
Across every sector and every country, the reasons organizations keep OS/2 running reduce to the same handful of factors:
- It does not break. OS/2's protected memory architecture means application crashes are isolated. A process dies; the OS does not. Systems have been documented running for years without a reboot — a claim no version of Windows can honestly make.
- Replacement is expensive, not the system. In certified environments — nuclear, aviation, medical, financial — changing the operating system is not a software project. It is a re-certification project. The new OS must be validated against every application, every hardware driver, and every regulatory requirement. The OS/2 system is already certified. The replacement has to earn that certification from scratch.
- IBM mainframe integration is native. OS/2 speaks IBM's enterprise protocols fluently. For organizations whose core infrastructure is an IBM mainframe, OS/2 workstations communicate with it natively in ways that Windows and Linux require additional middleware to replicate.
- It runs unattended in hostile environments. Offshore platforms, transit tunnels, ski resort ticket booths, nuclear plant control rooms — OS/2 systems in these locations often go years between physical maintenance visits. An OS that keeps running without intervention is not a historical curiosity; it is an operational requirement.
- ArcaOS has extended the viable runway. The existence of ArcaNoae and ArcaOS means that organizations with OS/2 deployments now have a path to modern hardware support, USB drivers, UEFI boot, and NVMe storage — without replacing their application software. This is not a museum piece being kept alive for sentiment. It is an engineering platform receiving active maintenance releases, most recently ArcaOS 5.1.2 on March 8, 2026.
Sources: OS/2 Wikipedia deployment records; ArcaNoae.com; Hackaday OS/2 coverage; OS2World.com wiki; The Register ArcaOS coverage; American Banker OS/2 ATM reporting; Wikipedia entries for Bank Saderat Iran, Diebold Nixdorf, Wincor Nixdorf, New York City Subway; IAEA nuclear I&C legacy system documentation; Russ Harvey Consulting OS/2 resource archive.
| Date | Changed By | Note |
|---|---|---|
| April 21, 2026 11:37 PM | pagetelegram | — |