# The 50 Best-Funded Quantum Computing Companies of 2026, and How Developers Can Contribute to Each Nov 10, 2026 · @Sid ## The short version: the money and the code are in different places Forty quantum companies have each raised $100M or more, about $27.3B in total as of 9 Nov 2026. IonQ alone has raised $6.1B, more than the next two combined. But funding is a poor guide to where a developer can actually contribute. Twenty of the 45 independent companies here publish no SDK at all. Even IonQ, the best-funded of them, keeps its main integrations inside Qiskit and Cirq. For this guide I checked 106 of these companies' GitHub repos on 10 Nov 2026: - 67 (63%) had a commit in the previous 30 days. - 63 (59%) have a contributing guide. - 13 had no commit at all in 2026. They include Rigetti's Quil compiler and Microsoft's original Quantum Katas. My take: if you want to break into quantum as a developer, ignore the funding league table. Start with PennyLane (Xanadu), Ocean (D-Wave), Bloqade (QuEra), TKET and Guppy (Quantinuum), or Deltakit (Riverlane). Riverlane has raised $120M, about 2% of IonQ's total, yet its community fund pays $2,000–4,000 per merged Deltakit feature. Below, each of the 50 companies gets its funding, focus, moat, links and the exact repos to start with. That covers the 40 that raised $100M+, five smaller companies with notable technology, and IBM, Google, Microsoft, AWS and NVIDIA. Python gets you into most SDKs. Rust and C++ are scarce and valued in compilers and simulators, and FPGA engineers are wanted in control systems and decoders. ## How the companies were ranked and their GitHub checked Companies are ranked by total capital raised. The five big-tech programs come last, since they don't raise money separately for quantum. - **Total raised** counts equity: private rounds, IPO and SPAC proceeds, and public offerings, as of 9 Nov 2026. Government grants, contracts and Commerce Department letters of intent are mentioned separately and not added in. Many totals are sums of disclosed rounds, not audited figures. Chinese totals are media-reported, and "(unverified)" marks anything weaker. - **Moat** is what makes a company's position hard to copy: IP, manufacturing, distribution, developer mindshare or sovereign backing. - **Start contributing** is based on a scan of each repo's default branch on 10 Nov 2026. It records the last commit date, whether there is a contributing guide, any contributor license agreement (CLA) or commit sign-off rule, and the dominant languages. "Active" means a commit in the last 30 days. - Star counts and open good-first-issue counts are not included. Where a repo documents a `good first issue` or `help wanted` label, that is noted so you know where to look. - Some companies on the list are quantum-adjacent rather than quantum computing: post-quantum crypto chips, QKD, lasers and sensing. They are included because they raised $100M+ on quantum businesses, and they are flagged. Each profile ends with **Links** (website, company X account, GitHub org, and named leaders where verified) and, where one exists, **Programs**: hackathons, grants, free credits and forums. X handles come from the source tracker. A missing handle means it couldn't be verified, not that the company has none. ## All 50 quantum computing companies, ranked by funding (Nov 2026) IonQ alone has raised more than the next two companies combined. Twenty of the 45 independent companies have no public SDK, so for those the developer path either runs through a partner cloud or doesn't exist yet. | # | Company | Raised | Modality / focus | Listing | Best first repo | Language | | --- | --- | --- | --- | --- | --- | --- | | 1 | IonQ | $6.1B | Trapped ion | NYSE: IONQ | [qiskit-community/qiskit-ionq](https://github.com/qiskit-community/qiskit-ionq) | Python | | 2 | Quantinuum | $2.9B | Trapped ion | Nasdaq: QNT | [quantinuum/tket](https://github.com/quantinuum/tket) | C++, Python | | 3 | PsiQuantum | $1.7B | Photonic | Private | [PsiQ/bartiq](https://github.com/PsiQ/bartiq) | Python | | 4 | Quantum Computing Inc | $1.7B | Photonic optimization | Nasdaq: QUBT | No public SDK | | | 5 | D-Wave Quantum | $1.3B | Annealing + gate model | NYSE: QBTS | [dwavesystems/dimod](https://github.com/dwavesystems/dimod) | Python, C++ | | 6 | Rigetti Computing | $1.0B | Superconducting | Nasdaq: RGTI | [rigetti/pyquil](https://github.com/rigetti/pyquil) | Python | | 7 | SandboxAQ | $1.0B | PQC + AI simulation software | Private | No public SDK | | | 8 | IQM | $890M | Superconducting | Nasdaq: IQMX | [iqm-finland/KQCircuits](https://github.com/iqm-finland/KQCircuits) | Python | | 9 | Infleqtion | $833M | Neutral atom | NYSE: INFQ | [Infleqtion/client-superstaq](https://github.com/Infleqtion/client-superstaq) | Python | | 10 | Pasqal | $800M | Neutral atom | Nasdaq: PSQL | [pasqal-io/Pulser](https://github.com/pasqal-io/Pulser) | Python | | 11 | Multiverse Computing | $800M | Quantum-inspired AI compression | Private | No public SDK | | | 12 | Oratomic | $775M | Neutral atom | Private | No public SDK | | | 13 | Xanadu | $620M | Photonic | Nasdaq: XNDU | [PennyLaneAI/pennylane](https://github.com/PennyLaneAI/pennylane) | Python | | 14 | Origin Quantum | $620M | Superconducting | Private | [OriginQ/QPanda-2](https://github.com/OriginQ/QPanda-2) | C++, Python | | 15 | SEALSQ | $575M | PQC chips (adjacent) | Nasdaq: LAES | [sealsq/vaultic-408-openssl-provider](https://github.com/sealsq/vaultic-408-openssl-provider) | C | | 16 | Oxford Quantum Circuits | $490M | Superconducting | Private | [oqc-community/qat](https://github.com/oqc-community/qat) | Python | | 17 | QuantumCTek | $370M | QKD networks (adjacent) | STAR: 688027 | No public SDK | | | 18 | SpinQ | $360M | Superconducting + NMR | Private | [SpinQTech/SpinQit](https://github.com/SpinQTech/SpinQit) | Python | | 19 | Photonic Inc. | $355M | Silicon spin-photon | Private | [PhotonicInc/ComputingEfficientlyInQLDPCCodes](https://github.com/PhotonicInc/ComputingEfficientlyInQLDPCCodes) | Python | | 20 | QBoson | $285M | Optical Ising machine | Private | [QBoson/kaiwu-pytorch-plugin](https://github.com/QBoson/kaiwu-pytorch-plugin) | Python | | 21 | Quantum Machines | $280M | Control systems | Private | [qua-platform/qua-libs](https://github.com/qua-platform/qua-libs) | Python | | 22 | Precilasers | $267M | Precision lasers (adjacent) | STAR: 688826 | No public SDK | | | 23 | QuEra Computing | $250M | Neutral atom | Private | [QuEraComputing/bloqade-circuit](https://github.com/QuEraComputing/bloqade-circuit) | Python | | 24 | Quantum Motion | $240M | Silicon spin | Private | No public SDK | | | 25 | Arqit Quantum | $240M | Quantum-safe keys (adjacent) | Nasdaq: ARQQ | No public SDK | | | 26 | TuringQ | $240M | Photonic | Private | [TuringQ/deepquantum](https://github.com/TuringQ/deepquantum) | Python | | 27 | CIQTEK | $240M | Quantum sensing (adjacent) | STAR: 688828 | No public SDK | | | 28 | QuantWare | $213M | Superconducting QPU supplier | Private | No public SDK | | | 29 | Classiq | $205M | Software (Intel deal pending) | Private | [Classiq/classiq-library](https://github.com/Classiq/classiq-library) | Python, Qmod | | 30 | Atom Computing | $200M | Neutral atom | Private | [microsoft/qdk](https://github.com/microsoft/qdk) (via Azure) | Rust, Q#, Python | | 31 | Horizon Quantum | $180M | Software | Nasdaq: HQ | No public SDK | | | 32 | Quantum Art | $164M | Trapped ion | Private | No public SDK | | | 33 | Quobly | $155M | Silicon spin | Private | [quobly-sw/SpinPulse](https://github.com/quobly-sw/SpinPulse) | Python | | 34 | Alice & Bob | $150M | Superconducting cat qubits | Private | [Alice-Bob-SW/qiskit-alice-bob-provider](https://github.com/Alice-Bob-SW/qiskit-alice-bob-provider) | Python, Rust | | 35 | Taiyi Quantum | $143M | Neutral atom | Private | No public SDK | | | 36 | Sygaldry Technologies | $139M | Quantum for AI infrastructure | Private | No public SDK | | | 37 | Q-CTRL | $130M | Control and error suppression | Private | [qctrl/open-controls](https://github.com/qctrl/open-controls) | Python | | 38 | Silicon Quantum Computing | $130M | Silicon donor atoms | Private | No public SDK | | | 39 | Universal Quantum | $125M | Trapped ion | Private | No public SDK | | | 40 | Riverlane | $120M | Error-correction stack | Private | [Deltakit/deltakit](https://github.com/Deltakit/deltakit) | Python | | 41 | SEEQC | \~$85M | Superconducting digital control | Private | No public SDK | | | 42 | Quandela | \~$78M | Photonic | Private | [Quandela/Perceval](https://github.com/Quandela/Perceval) | Python | | 43 | Diraq | \~$65M | Silicon spin | Private | No public SDK | | | 44 | planqc | \~$59M | Neutral atom | Private | No public SDK | | | 45 | Nord Quantique | \~$38M | Bosonic superconducting | Private | No public SDK | | | 46 | IBM Quantum | Internal | Superconducting | NYSE: IBM | [Qiskit/qiskit](https://github.com/Qiskit/qiskit) | Python, Rust | | 47 | Google Quantum AI | Internal | Superconducting | Nasdaq: GOOGL | [quantumlib/Cirq](https://github.com/quantumlib/Cirq) | Python | | 48 | Microsoft Quantum | Internal | Topological + neutral-atom partners | Nasdaq: MSFT | [microsoft/qdk](https://github.com/microsoft/qdk) | Rust, Q#, Python | | 49 | AWS (Amazon Braket) | Internal | Cloud access + cat qubits | Nasdaq: AMZN | [amazon-braket/amazon-braket-sdk-python](https://github.com/amazon-braket/amazon-braket-sdk-python) | Python | | 50 | NVIDIA | Internal | GPU-quantum hybrid | Nasdaq: NVDA | [NVIDIA/cuda-quantum](https://github.com/NVIDIA/cuda-quantum) | C++, Python | Raised is total equity in USD as of 9 Nov 2026. Rows 41–45 are below $100M, and rows 46–50 fund quantum internally. ## Trapped-ion and neutral-atom hardware Ions and atoms hold today's fidelity and logical-qubit records, and they've drawn about $12B of the capital. Quantinuum, Pasqal and QuEra have the deepest open-source surfaces. IonQ's integrations live mostly inside Qiskit and Cirq. ### 1. IonQ ($6.1B, NYSE: IONQ) - **Funding:** It closed a $2.0B registered direct offering at $40/share in Oct 2026 (Heights Capital), leaving \~$3.7B pro-forma cash. Earlier backers include NEA, GV, Amazon and Samsung. - **Focus:** Trapped-ion QPUs: Forte (\~36 qubits) and Tempo (100 qubits). After buying Oxford Ionics it switched to chip-based electronic qubit control. It also owns the SkyWater foundry. The roadmap is 256-qubit Superion deliveries in 2027 and \~2M physical qubits by 2030. - **Moat:** It has the biggest balance sheet in pure-play quantum and the most revenue: $173.8M in Q3 2026, with FY26 guidance of $505–515M. It also owns a US-trusted fab and is on every major cloud. - **Start contributing:** - [ionq-core](https://github.com/ionq/ionq-core) is the cloud API client (Python, active 9 Nov). Run `uv sync`, then `uv run pytest`. A 100% branch-coverage gate applies. - [qiskit-ionq](https://github.com/qiskit-community/qiskit-ionq) is the official Qiskit provider (Python, active 3 Nov). It has a contributing guide and uses pytest. - [blqs](https://github.com/ionq/blqs) offers building blocks for quantum DSLs (Python, last commit Aug 2026). **Links:** [Website](https://www.ionq.com) · [X @IonQ\_Inc](https://x.com/IonQ_Inc) · [GitHub](https://github.com/ionq) · CEO [@NiccoloDeMasi](https://x.com/NiccoloDeMasi). **Programs:** [Research Credits](https://ionq.com/programs/research-credits) give academics up to $10,000 of QPU time. The IonQ simulator is free on Azure Quantum, and IonQ sponsored a challenge at iQuHACK 2026. ### 2. Quantinuum ($2.9B, Nasdaq: QNT) - **Funding:** Its June 2026 IPO raised $1.68B at $60/share, valuing it at \~$14.3B, with $1.94B cash at 30 Sep. Honeywell keeps control. JPMorgan, Mitsui, Amgen and NVentures are holders. - **Focus:** The QCCD trapped-ion architecture. Helios has 98 barium qubits at 99.921% two-qubit fidelity. Sol is due in 2H 2027, and Apollo targets full fault tolerance by 2029. - **Moat:** It has the highest commercial physical and logical fidelities and a leading error-correction record. Its software stack (TKET, Guppy, Nexus) is widely used. - **Start contributing:** This is the richest compiler codebase outside IBM and Google. - [tket](https://github.com/quantinuum/tket) is the C++ compiler core with pytket bindings (active 9 Nov). It has a contributing guide. Fork and open a PR, and format C++ with `clang-format`. - [guppylang](https://github.com/quantinuum/guppylang) is a Pythonic quantum-classical language for Helios (Python, active 6 Nov). - [hugr](https://github.com/quantinuum/hugr) is a hybrid program IR written in Rust (active 5 Nov). It's a good target if you know compilers or MLIR-style IRs. - [selene](https://github.com/quantinuum/selene) is a hybrid emulator (Rust and Python, active 3 Nov). [lambeq](https://github.com/quantinuum/lambeq) is a quantum NLP library (Python). **Links:** [Website](https://www.quantinuum.com) · [X @QuantinuumQC](https://x.com/QuantinuumQC) · [GitHub](https://github.com/quantinuum) · [@rajeeb\_hazra](https://x.com/rajeeb_hazra) (CEO) · [@coecke](https://x.com/coecke). **Programs:** The [SG Grand Challenge 2026](https://quantumzeitgeist.com/quantinuum-quantum-challenge-computing-solutions/) is a three-month global program for researchers and developers, with finals in Singapore. ### 9. Infleqtion ($833M, NYSE: INFQ) - **Funding:** It went public in Feb 2026 through a de-SPAC with Churchill Capital X, raising more than $550M gross including the PIPE. Cash was $582M with no debt at 30 Jun. - **Focus:** Neutral-atom computing (the Sqale system) alongside atomic clocks, RF receivers and inertial sensors. It reported 30 logical qubits via error detection in Sep 2026 and targets 100 logical qubits by end-2028. - **Moat:** It is the only listed neutral-atom company with diversified revenue (\~$45M FY26 guidance), backed by 17+ years of ColdQuanta cold-atom engineering. - **Start contributing:** - [client-superstaq](https://github.com/Infleqtion/client-superstaq) provides qiskit-superstaq, cirq-superstaq and SupermarQ benchmarks (Python, active 6 Nov). It has no contributing guide, so open an issue first. - [resource-superstaq](https://github.com/Infleqtion/resource-superstaq) is a fault-tolerant resource estimator (Python, active 26 Oct). - [qLDPC](https://github.com/qLDPCOrg/qLDPC) is community tooling for qLDPC and stabilizer codes (Python, active 9 Nov). **Links:** [Website](https://infleqtion.com) · [X @infleqtion](https://x.com/infleqtion) · [GitHub](https://github.com/Infleqtion). ### 10. Pasqal ($800M, Nasdaq: PSQL) - **Funding:** It raised €170M of equity plus a \~$200M convertible in Mar 2026. The Bleichroeder II SPAC closed in Aug 2026 with \~$356M cash. Investors include Temasek, Bpifrance, Aramco's Wa'ed and LG. - **Focus:** Rubidium atom arrays in analog and digital modes, with 1,024-atom defect-free registers in 2026. Logical registers are promised within \~12 months, and >200 logical qubits by end-2029. - **Moat:** It is Europe's neutral-atom champion, with the most on-prem neutral-atom QPUs at HPC centres and the largest analog-mode software ecosystem. - **Start contributing:** - [Pulser](https://github.com/pasqal-io/Pulser) handles pulse-level control and emulation (Python, active 6 Nov). Its contributing guide asks you to get the issue assigned to you first and to open PRs against `develop`. Run `pip install -r dev_requirements.txt`, then `pytest`. - [emulators](https://github.com/pasqal-io/emulators), [pasqal-cloud](https://github.com/pasqal-io/pasqal-cloud) and [qoolqit](https://github.com/pasqal-io/qoolqit) are all active in Nov 2026. qadence and pyqtorch have gone quiet (last commits Dec and Jun 2025). **Links:** [Website](https://www.pasqal.com) · [X @PasqalQuantum](https://x.com/PasqalQuantum) · [GitHub](https://github.com/pasqal-io) · [Community](https://www.pasqal.com/community/). **Programs:** It runs the Blaise Pascal Quantum Challenge hackathon ([2025 edition](https://www.agorize.com/en/challenges/blaisepascalquantumchallenge2025)). ### 12. Oratomic ($775M, private) - **Funding:** It launched in Mar 2026 and raised a \~$475M Series B in Oct 2026, co-led by ARCH, Spark, Khosla, Index, General Catalyst and Bezos Expeditions. Its post-money valuation is \~$5.4B (unverified). - **Focus:** It is skipping NISQ to build a fault-tolerant machine on reconfigurable atom arrays. A Caltech paper estimates that Shor's algorithm needs as few as \~10,000 atoms. The target date is \~2030. - **Moat:** It has one of the densest neutral-atom and QEC teams anywhere, including Bluvstein, Endres and Preskill. - **Start contributing:** It has no public SDK. Follow the Caltech papers, and practice with QEC tools such as [Stim](https://github.com/quantumlib/Stim) and [tsim](https://github.com/QuEraComputing/tsim). **Links:** [Website](https://www.oratomic.com) · [GitHub](https://github.com/Oratomic-Inc) (no public repos) · co-founder [@preskill](https://x.com/preskill). ### 23. QuEra Computing ($250M+, private) - **Funding:** It raised $230M+ in Feb 2025 from Google, SoftBank Vision Fund 2 and Valor, and NVentures joined later. Its valuation is \~$1B (unverified). - **Focus:** Rubidium arrays. Aquila (256-qubit analog) is on Amazon Braket. The Libra fault-tolerant system, with >256 logical qubits, is due on Braket in 2028. - **Moat:** It has an exclusive pipeline to the Harvard and MIT labs behind the 48-logical-qubit demonstrations, plus backing from Google, AWS and NVIDIA. - **Start contributing:** This is the strongest open-source organization among private hardware companies. - [bloqade-circuit](https://github.com/QuEraComputing/bloqade-circuit) provides circuit eDSLs (Python, active 3 Nov). It has a contributing guide. Run `pre-commit install`, then `pytest`. - [kirin](https://github.com/QuEraComputing/kirin) is compiler infrastructure (Python, active 5 Nov). - [tsim](https://github.com/QuEraComputing/tsim) is a fast QEC sampler (active 7 Nov). - [bloqade-analog](https://github.com/QuEraComputing/bloqade-analog) covers Aquila. [Bloqade.jl](https://github.com/QuEraComputing/Bloqade.jl) is the Julia simulator, slower lately (last commit Apr 2026). **Links:** [Website](https://www.quera.com) · [X @QueraComputing](https://x.com/QueraComputing) · [GitHub](https://github.com/QuEraComputing) · [Forum](https://forum.quera.com). **Programs:** It sponsored an iQuHACK 2026 challenge. Its Aquila QPU is pay-per-use on Amazon Braket, and the Braket free tier covers simulators only. ### 30. Atom Computing (\~$180M equity; $300M+ including a Commerce LOI, private) - **Funding:** It raised a $100M Series C in Jun 2026 led by Third Point, alongside DCVC and Cisco, plus a $100M US Commerce letter of intent. - **Focus:** It was the first company past 1,000 gate-based neutral-atom qubits (AC1000 has 1,200+). The Magne system for Denmark targets 50 logical qubits around early 2027. It is in DARPA QBI Stage C. - **Moat:** It is the hardware half of Microsoft's fault-tolerant stack, with DARPA and sovereign validation. - **Start contributing:** It has no SDK of its own. Build through Microsoft's [qdk](https://github.com/microsoft/qdk) and [azure-quantum-python](https://github.com/microsoft/azure-quantum-python) (see Microsoft, below). **Links:** [Website](https://atom-computing.com) · [X @atom\_computing](https://x.com/atom_computing) · [GitHub](https://github.com/atom-computing). ### 32. Quantum Art ($164M, private) - **Funding:** Its Series A totals $140M after a $40M extension in Apr 2026 (Bedford Ridge, Hudson Bay, Poalim). - **Focus:** Multi-core trapped-ion chains with optical segmentation and native multi-qubit gates. It has shown a 200-ion chain and targets a 1,000-qubit system around 2027. - **Moat:** An architecture that keeps all-to-all connectivity while scaling, plus Weizmann Institute IP. - **Start contributing:** It has no public SDK and no cloud access yet. **Links:** [Website](https://www.quantum-art.tech). ### 35. Taiyi Quantum ($143M, private) - **Funding:** It raised more than CNY 1B within \~8 months, through an A round in Oct 2026 (media-reported). - **Focus:** Ytterbium neutral atoms. It targets a logical-qubit demonstration by end-2026. - **Moat:** It is China's first full-system ytterbium neutral-atom company, led by a former Microsoft quantum architect. - **Start contributing:** It has no public SDK. ### 39. Universal Quantum ($125M+, private) - **Funding:** It raised a Series A of more than $100M in Oct 2026, co-led by DCVC and Firgun. - **Focus:** Trapped ions driven by microwaves and voltages instead of per-ion lasers. Chiplets are linked by UQConnect ion shuttling at a reported 99.999993% transfer fidelity. - **Moat:** A foundry-friendly design without lasers, plus a €67M DLR contract. - **Start contributing:** It has no public SDK. **Links:** [Website](https://universalquantum.com) · [X @universalquant](https://x.com/universalquant). ### 44. planqc (\~$59M equity, private) - **Funding:** It has raised €54.6M of equity, plus about €49M more in government contracts. - **Focus:** Neutral atoms, spun out of the Max Planck Institute of Quantum Optics in Garching. - **Moat:** Close ties to the Max Planck groups and sovereign German demand. - **Start contributing:** No public SDK was found. **Links:** [Website](https://www.planqc.eu). ## Superconducting, photonic, spin and annealing hardware This is the most crowded part of the map, with 21 companies. It also has the two best contribution targets of any hardware startup: Xanadu's PennyLane and D-Wave's Ocean. Silicon-spin companies are the least open, and none of the five has a real SDK yet. ### 3. PsiQuantum ($1.7B, private) - **Funding:** It raised a $1B Series E at $7B post in Sep 2025 (BlackRock, Temasek, Baillie Gifford, NVentures). A May 2026 round of $1.5B at $10.5B is unverified. Australian and Illinois government packages come on top. - **Focus:** Silicon-photonic qubits in a fusion-based architecture, made at GlobalFoundries. It is building utility-scale sites in Brisbane (target \~end-2027) and Chicago (\~2028). - **Moat:** CMOS-fab manufacturing, cryo-cabinet operation at 2–4K instead of dilution fridges, and sovereign anchor deals. - **Start contributing:** Its repos are for fault-tolerant algorithm work, not hardware access. - [bartiq](https://github.com/PsiQ/bartiq) does symbolic resource estimation (Python, active 26 Oct). - [qref](https://github.com/PsiQ/qref) is an open format for resource estimates (active 6 Nov). - [psiqdk](https://github.com/PsiQ/psiqdk) is the Workbench development kit, and [workbench-quantum-katas](https://github.com/PsiQ/workbench-quantum-katas) offers fault-tolerance tutorials. - None has a contributing guide, so start with an issue. **Links:** [Website](https://www.psiquantum.com) · [X @PsiQuantum](https://x.com/PsiQuantum) · [GitHub](https://github.com/PsiQ) · co-founder [@PeteShadbolt](https://x.com/PeteShadbolt). **Programs:** The [Brisbane Undergraduate Mentorship](https://www.psiquantum.com/australia-undergrad-mentorship-2026) is free for Queensland undergraduates (Sep–Oct 2026). ### 4. Quantum Computing Inc ($1.7B, Nasdaq: QUBT) - **Funding:** It has raised $1.64B since Nov 2024 through private placements, including $750M in Oct 2025. It held \~$1.3B in cash at mid-2026. - **Focus:** Room-temperature photonic optimization (the Dirac-3 "entropy quantum computing" machine) and a thin-film lithium niobate chip foundry in Arizona. - **Moat:** A domestic TFLN fab and a large cash pile. Its computing claims are disputed, and it does not have a gate-model roadmap. - **Start contributing:** It has no public SDK. **Links:** [Website](https://quantumcomputinginc.com) · [X @QciQuantum](https://x.com/QciQuantum). ### 5. D-Wave Quantum ($1.3B, NYSE: QBTS) - **Funding:** Equity offerings include a $400M at-the-market (ATM) raise in Jun 2025. In Jan 2026 it bought Quantum Circuits Inc. for $550M, and it has a $100M Commerce LOI. Cash was $546M at 30 Jun. - **Focus:** Annealers (Advantage2, \~4,400 qubits), plus a new gate-model track using Quantum Circuits' dual-rail qubits. The gate-model roadmap reaches 100 logical qubits by 2032. - **Moat:** The only commercial-scale annealing business, with 25+ years of IP and the most enterprise production deployments. - **Start contributing:** Ocean is a mature, well-structured Python stack. - [dimod](https://github.com/dwavesystems/dimod) is the shared QUBO/Ising/CQM model API (Python and C++, active 3 Nov). It has a contributing guide. - [dwave-optimization](https://github.com/dwavesystems/dwave-optimization) is the nonlinear model library (C++ core, active 3 Nov) and is good for C++ developers. [minorminer](https://github.com/dwavesystems/minorminer) does graph embedding. - [dwave-system](https://github.com/dwavesystems/dwave-system) and [dwave-pytorch-plugin](https://github.com/dwavesystems/dwave-pytorch-plugin) are active. Install everything with [dwave-ocean-sdk](https://github.com/dwavesystems/dwave-ocean-sdk). **Links:** [Website](https://www.dwavequantum.com) · [X @dwavequantum](https://x.com/dwavequantum) · [GitHub](https://github.com/dwavesystems) · CEO [@Alan\_Baratz](https://x.com/Alan_Baratz). **Programs:** New Leap sign-ups get a [trial plan and the community forums](https://support.dwavesys.com/hc/en-us/articles/360003680734). Businesses can apply to the [Leap Quantum LaunchPad](https://thequantuminsider.com/2025/01/22/d-wave-announces-new-leap-quantum-launchpad-program-to-support-quantum-computing-applications/), which offers free trials. ### 6. Rigetti Computing ($1.0B, Nasdaq: RGTI) - **Funding:** It raised a $350M ATM in Jun 2025. A US Commerce CHIPS equity award of up to $100M followed in Sep 2026 ($43.9M initial). Cash was $541M with no debt at 30 Jun. - **Focus:** Superconducting chiplets made in its own Fab-1. Cepheus-1-108Q is generally available at \~99.1% two-qubit fidelity, and it targets \~1,000 qubits in \~3 years. - **Moat:** Its own fab, fast \~60ns gates, and the Quil ISA. Fidelity lags IBM and Google. - **Start contributing:** - [pyquil](https://github.com/rigetti/pyquil) is the Python SDK (active 30 Oct). Its guide points to `good first issue` and `help wanted` labels. Set up with `poetry install`, and ask questions in the Rigetti Forest Slack. - [qcs-sdk-rust](https://github.com/rigetti/qcs-sdk-rust) is the Rust SDK with Python bindings (active 4 Nov). - [quilc](https://github.com/quil-lang/quilc) and [qvm](https://github.com/quil-lang/qvm) are a rare chance to work on a Common Lisp compiler and simulator, though both were last committed in Oct 2025. **Links:** [Website](https://www.rigetti.com) · [X @rigetti](https://x.com/rigetti) · [GitHub](https://github.com/rigetti). **Community:** The Rigetti Forest Slack is linked from the pyquil guide. Rigetti's QVM simulator is [free on Azure Quantum](https://learn.microsoft.com/azure/quantum/pricing). ### 8. IQM ($890M, Nasdaq: IQMX) - **Funding:** It raised a $320M Series B in Sep 2025 (Ten Eleven) and then completed its RAAQ de-SPAC in Jul 2026 for \~$233.5M net. Pro-forma cash is €309M. - **Focus:** Full-stack superconducting systems built in its own Espoo fab. It has sold 26 on-prem systems, the most of any vendor, and the 150-qubit Halocene line is error-correction ready. It targets fault tolerance by 2030. - **Moat:** A sticky installed base at European HPC centres and sovereign EU procurement. - **Start contributing:** - [KQCircuits](https://github.com/iqm-finland/KQCircuits) is a KLayout library for designing superconducting chips (Python, last commit Jul 2026). It's a unique way into hardware design. An individual CLA via IQM's website is required. - [sdk](https://github.com/iqm-finland/sdk) provides iqm-client with Qiskit and Cirq adapters (active 21 Oct). - [QDMI-on-IQM](https://github.com/iqm-finland/QDMI-on-IQM) handles HPC integration (C++ and Python, active 9 Nov). It has a contributing guide. **Links:** [Website](https://meetiqm.com) · [X @IQMquantum](https://x.com/IQMquantum) · [GitHub](https://github.com/iqm-finland) · CEO [@JanGoetz6](https://x.com/JanGoetz6). **Programs:** The [IQM Resonance Starter](https://quantumzeitgeist.com/iqm-boosts-cloud-platform-with-54-qubit-system-free-tier/) tier is free, with up to 30 credits a month on selected QPUs. IQM sponsored an iQuHACK 2026 challenge. ### 13. Xanadu ($620M, Nasdaq/TSX: XNDU) - **Funding:** About $250M private, a \~$302M de-SPAC in Mar 2026, and $67M drawn from a $300M Yorkville facility. It also has CAD 195M in Canadian government support. - **Focus:** Photonic chips networked over fibre. Its Qubit Factory is being built in 2026–27, and it targets 200 logical qubits by 2029. - **Moat:** PennyLane, used by \~31% of surveyed quantum developers, gives it mindshare that doesn't depend on its hardware. - **Start contributing:** This is the best single contribution target among hardware startups. - [pennylane](https://github.com/PennyLaneAI/pennylane) does differentiable programming and QML (Python, active 9 Nov). Its guide links a curated `good first issue` page, and a dev dependency group in `pyproject.toml` sets up your environment. - [catalyst](https://github.com/PennyLaneAI/catalyst) is an MLIR-based JIT compiler (Python and C++, active 9 Nov). - [pennylane-lightning](https://github.com/PennyLaneAI/pennylane-lightning) is a C++/GPU simulator (active 5 Nov). - [demos](https://github.com/PennyLaneAI/demos) is the easiest place for a first PR. **Links:** [Website](https://www.xanadu.ai) · [X @XanaduAI](https://x.com/XanaduAI) · [GitHub](https://github.com/PennyLaneAI) · [@3rdquantization](https://x.com/3rdquantization). **Programs and community:** The [QHack Coding Challenge](https://pennylane.ai/blog/2026/08/september-events) ran 16–23 Oct 2026 with cash prizes. PennyLane put [bounties into unitaryHACK 2026](https://pennylane.ai/blog/2026/05/claim-bounties-from-pennylane-in-unitaryhack-2026/). Its [forum](https://discuss.pennylane.ai) is the main help channel, alongside Discord and Slack. ### 14. Origin Quantum ($620M, private) - **Funding:** It raised a \~CNY 3B pre-IPO round in Jun 2026 at \~$3.4B post (state and defence funds). A STAR Market IPO is in preparation. - **Focus:** China's full-stack superconducting champion: Wukong-72 and the 4th-generation Wukong-180, plus the Origin Pilot OS. - **Moat:** State backing, an in-house chip line, and a protected domestic market. - **Start contributing:** - [pyqpanda-algorithm](https://github.com/OriginQ/pyqpanda-algorithm) covers finance, ML and optimization algorithms for QPanda3 (Python, Feb 2026). Its contributing guide is in Chinese, and you claim `good first issue` tasks by asking to be assigned. - [QPanda-2](https://github.com/OriginQ/QPanda-2) (C++) has been inactive since Nov 2024. **Links:** [Website](https://originqc.com.cn) · [GitHub](https://github.com/OriginQ). ### 16. Oxford Quantum Circuits ($490M, private) - **Funding:** It raised a £260M (\~$350M) Series C in Jun 2026, led by Bullhound with a £100M British Business Bank anchor. - **Focus:** Coaxmon and dual-rail "Dimon" qubits on sapphire, deployed in colocation data centres. Its roadmap: 16 logical qubits in 2026, 200 in 2028 and 50,000 by 2034. - **Moat:** Patented 3D wiring IP and an early lead in data-centre deployments. - **Start contributing:** - [qat](https://github.com/oqc-community/qat) is a low-level compiler and runtime (Python, active 5 Nov). Its guide explicitly sets aside `good first issue` tasks for newcomers and `help wanted` for larger work. - [rasqal](https://github.com/oqc-community/rasqal) is a Rust hybrid runtime, quiet since Jul 2025. [erado](https://github.com/oqc-community/erado) simulates erasure noise. **Links:** [Website](https://oqc.tech) · [X @oqc\_tech](https://x.com/oqc_tech) · [GitHub](https://github.com/oqc-community). ### 18. SpinQ ($360M, private) - **Funding:** It raised CNY 2B in H1 2026, including a CNY 1B Series D in Jun (media-reported). - **Focus:** Superconducting chips (25 and 103 qubits) and NMR desktop machines for education. It targets a d=3 surface-code demonstration in 2026. - **Moat:** A vertically integrated Chinese stack and 200+ education installs. - **Start contributing:** - [SpinQit](https://github.com/SpinQTech/SpinQit) is the SDK (Python with a C++ core, active 10 Oct). - [spinqit\_mcp\_tools](https://github.com/SpinQTech/spinqit_mcp_tools) is an MCP server for SpinQ Cloud, useful if you build AI agents. **Links:** [Website](https://www.spinquanta.com) · [GitHub](https://github.com/SpinQTech). ### 19. Photonic Inc. ($355M, private) - **Funding:** It closed a growth round of more than $200M in May 2026 at $2B post (Planet First, Microsoft, BCI, RBC, TELUS). - **Focus:** T-centre spin qubits in silicon that emit telecom photons, networked with qLDPC codes. It is in DARPA QBI Stage B. - **Moat:** A native compute-plus-network qubit and the SHYPS code IP. - **Start contributing:** Only paper code is public ([ComputingEfficientlyInQLDPCCodes](https://github.com/PhotonicInc/ComputingEfficientlyInQLDPCCodes)). It's useful reading for qLDPC. **Links:** [Website](https://photonic.com) · [GitHub](https://github.com/PhotonicInc). ### 20. QBoson ($285M, private) - **Funding:** About CNY 2B across 10 rounds, including a CNY 1B Series B in Mar 2026 (media-reported). - **Focus:** A room-temperature coherent optical Ising machine for QUBO problems, at 1,000+ "qubits". - **Moat:** It is China's leader in coherent Ising machines, but those qubits aren't comparable with gate-model qubits. - **Start contributing:** [kaiwu-pytorch-plugin](https://github.com/QBoson/kaiwu-pytorch-plugin) (Python, active 5 Nov) and [kaiwu\_community](https://github.com/QBoson/kaiwu_community) both have contributing docs. **Links:** [Website](https://www.qboson.com) · [GitHub](https://github.com/QBoson). It also publishes a coding-agent skill for its Kaiwu SDK ([kaiwu-coding-skill](https://github.com/QBoson/kaiwu-coding-skill)). ### 24. Quantum Motion ($240M+, private) - **Funding:** The second close of its Series C came in Sep 2026 (DCVC, Kembara, imec.xpand, Sony). - **Focus:** Silicon CMOS spin qubits on 300mm GlobalFoundries lines, with on-die cryo-CMOS control. It delivered a full-stack system to the UK NQCC and is in DARPA QBI Stage B. - **Moat:** Classical-chip manufacturing and tiny qubits. - **Start contributing:** It has no public SDK. **Links:** [Website](https://quantummotion.com). ### 26. TuringQ ($240M, private) - **Funding:** About CNY 1B in 2026 from national guidance funds and Pudong state capital, valuing it at more than CNY 7B. It began IPO tutoring in Aug 2026. - **Focus:** Integrated photonics on lithium niobate and laser-written glass, operating at room temperature. - **Moat:** Its own photonic chip pilot line and the SJTU research lineage. - **Start contributing:** [deepquantum](https://github.com/TuringQ/deepquantum) is a PyTorch-based photonic and qubit simulator for QML (active 8 Nov). Run `uv pip install -e ".[dev]"`, then `pre-commit install`. Ruff and Jupytext are enforced. **Links:** [Website](https://www.turingq.com) · [GitHub](https://github.com/TuringQ). ### 28. QuantWare ($213M, private) - **Funding:** It raised a €152M Series B in May 2026 (Intel Capital, In-Q-Tel, ETF Partners). - **Focus:** It is a merchant supplier of superconducting QPUs to 50+ customers. The VIO-40K chiplet system ships in 2028, and its KiloFab opens in 2026. - **Moat:** It aims to be the "TSMC of superconducting qubits", gaining yield data that no single system builder sees. - **Start contributing:** It has only forks (pyHFSS, scqubits). Its chips are integrated with CUDA-Q. **Links:** [Website](https://quantware.com) · [GitHub](https://github.com/QW-QubitDesign). ### 33. Quobly ($155M, private) - **Funding:** It raised a €115M Series A in Jun 2026, co-led by Bpifrance, SEALSQ and STMicroelectronics. - **Focus:** FD-SOI silicon spin qubits on 300mm wafers. Its first commercial system, Alloy Pioneer, is due on the cloud by end-2026. - **Moat:** CEA-Leti heritage and access to an STMicroelectronics-class fab. - **Start contributing:** [SpinPulse](https://github.com/quobly-sw/SpinPulse) does spin-qubit pulse simulation (Python, Apache-2.0, active 2 Nov). [Quobly-alloy](https://github.com/quobly-sw/Quobly-alloy) is the Alloy SDK. **Links:** [Website](https://www.quobly.io) · [GitHub](https://github.com/quobly-sw). ### 34. Alice & Bob ($150M, private) - **Funding:** It raised a €100M Series B in Jan 2025 (Future French Champions, AVP, Bpifrance), with an NVentures extension in May 2026. - **Focus:** Cat qubits that suppress bit flips in hardware, so a simple repetition code handles phase flips. It targets 100 logical qubits by 2030. - **Moat:** Patents behind a claimed \~200x reduction in qubit overhead. - **Start contributing:** - [qiskit-alice-bob-provider](https://github.com/Alice-Bob-SW/qiskit-alice-bob-provider) is the Qiskit provider (Python, active 3 Nov). - [anb-estimator](https://github.com/Alice-Bob-SW/anb-estimator) is a Rust extension of Microsoft's Q# resource estimator for cat qubits (active 12 Oct). It has a contributing guide. **Links:** [Website](https://alice-bob.com) · [X @Alice\_\_Bob](https://x.com/Alice__Bob) · [GitHub](https://github.com/Alice-Bob-SW). **Programs:** It sponsored an iQuHACK 2026 challenge. ### 38. Silicon Quantum Computing ($130M, private) - **Funding:** About A$193M+, most recently A$40M from Australia's NRFC in Jun 2026. - **Focus:** Phosphorus donor atoms placed with atomic precision using STM lithography. It can design, fabricate and test a new chip in about a week. - **Moat:** About 25 years of Simmons-group research and very long coherence times. - **Start contributing:** It has no public SDK. **Links:** [Website](https://www.sqc.com.au). ### 41. SEEQC (\~$85M, private) - **Funding:** Trackers put its equity at $79–89M, and an IPO is pending. - **Focus:** Digital single-flux-quantum (SFQ) chips that control and read qubits inside the fridge. - **Moat:** On-chip cryogenic control that removes most room-temperature wiring. - **Start contributing:** No public SDK was found. **Links:** [Website](https://seeqc.com). ### 42. Quandela (\~$78M, private) - **Funding:** A €15M Series A and a 2023 package of more than €50M that mixes equity, public funding and debt. - **Focus:** Photonic QPUs built on deterministic quantum-dot single-photon sources. - **Moat:** Photon-source IP from the C2N lab. - **Start contributing:** [Perceval](https://github.com/Quandela/Perceval) is a photonic circuit framework (Python, active 1 Oct). Its guide points to `help wanted` issues and asks you to raise large changes on the Perceval forum first. **Links:** [Website](https://www.quandela.com) · [GitHub](https://github.com/Quandela) · [Perceval forum](https://perceval.quandela.net/forum/). ### 43. Diraq (\~$65M equity, private) - **Funding:** About $65M of equity, with large non-dilutive funding from DARPA QBI and a CHIPS LOI on top. - **Focus:** CMOS silicon spin qubits spun out of UNSW. - **Moat:** Foundry-compatible qubits and DARPA validation. - **Start contributing:** No public SDK was found. **Links:** [Website](https://diraq.com). ### 45. Nord Quantique (\~$38M equity, private) - **Funding:** About $38M of equity plus \~$31M in government funding. - **Focus:** Bosonic qubits in superconducting cavities that build error correction into each qubit. - **Moat:** A hardware-efficient path to error correction. - **Start contributing:** No public SDK was found. **Links:** [Website](https://nordquantique.ca). **Programs:** It sponsored an iQuHACK 2026 challenge. ## Software, control, error correction and quantum-adjacent The picks-and-shovels layer is where non-physicists add value fastest. Control stacks, QEC decoders and synthesis compilers sell to every hardware maker, whichever qubit wins. Riverlane, Quantum Machines and Classiq run the most welcoming repos here. Five companies in this group are quantum-adjacent (security, lasers, sensing) and are marked as such. ### 7. SandboxAQ ($1.0B, private) - **Funding:** It raised \~$1B of primary equity, last valued at $5.75B (Series E, Apr 2025). It also has a $500M US Commerce CHIPS award (Jun 2026) in exchange for equity and royalties. A \~$13.9B secondary mark is unverified. - **Focus:** It doesn't build quantum computers. It sells AQtive Guard for post-quantum crypto migration, Large Quantitative Models for chemistry and materials, and AQNav for magnetic navigation. - **Moat:** Alphabet heritage, government equity and FedRAMP footholds, and proprietary physics simulation data. - **Start contributing:** Its quantum repos [Tangelo](https://github.com/sandbox-quantum/Tangelo) (chemistry) and [sandwich](https://github.com/sandbox-quantum/sandwich) (crypto API) are archived, so fork them but don't open PRs. Its most active repo, switch, is an AI-agent tool, not quantum. **Links:** [Website](https://www.sandboxaq.com) · [X @sandboxaq](https://x.com/sandboxaq) · [GitHub](https://github.com/sandbox-quantum) · CEO [@jackhidary](https://x.com/jackhidary). ### 11. Multiverse Computing ($800M, private) - **Funding:** A Series C of up to €500M (\~$570M) in Jul 2026 at €1.5B pre (Forgepoint, BNPP Solar Impulse, Bullhound). Final close is unclear. - **Focus:** Quantum-inspired tensor networks that compress LLMs (CompactifAI). It publishes open-weight compressed models such as HyperNova 60B. - **Moat:** Tensor-network know-how and European sovereign backing. Its "quantum" positioning is mostly branding. - **Start contributing:** Its single GitHub repo, [quantum\_genome\_assembly](https://github.com/Multiverse-Computing-SL/quantum_genome_assembly), is a research artifact. The real developer surface is its models on Hugging Face. **Links:** [Website](https://multiversecomputing.com) · [X @multiversecompu](https://x.com/multiversecompu) · [GitHub](https://github.com/Multiverse-Computing-SL). ### 15. SEALSQ ($575M+, Nasdaq: LAES), adjacent - **Funding:** It has raised $575M+ through registered direct offerings, warrants and ATMs since Nov 2024, including $125M in Mar 2026. - **Focus:** Secure-element chips and TPMs moving to NIST post-quantum algorithms (ML-KEM, ML-DSA). The QS7001 is starting production. - **Moat:** Certified secure silicon with long design-in cycles. - **Start contributing:** For embedded C developers, there's [vaultic-408-openssl-provider](https://github.com/sealsq/vaultic-408-openssl-provider) (an OpenSSL provider) and [Zero-Touch-Provisioning](https://github.com/sealsq/Zero-Touch-Provisioning). Both were last committed Apr 2026. **Links:** [Website](https://www.sealsq.com) · [X @SEALSQcorp](https://twitter.com/SEALSQcorp) · [GitHub](https://github.com/sealsq). ### 17. QuantumCTek ($370M, STAR: 688027), adjacent - **Funding:** Its IPO and a CNY 1.9B placement to China Telecom (2024). - **Focus:** China's largest QKD network vendor. It also supplies superconducting control electronics. - **Moat:** State control and China Telecom distribution. - **Start contributing:** It has no public SDK. **Links:** [Website](http://www.quantum-info.com). ### 21. Quantum Machines ($280M, private) - **Funding:** It raised a $170M Series C in Feb 2025 (PSG Equity, Intel Capital, Red Dot). - **Focus:** The OPX1000 control hardware and the QUA pulse language, integrated with NVIDIA DGX Quantum and NVQLink for real-time decoding. - **Moat:** It claims more than 50% of quantum-computer builders use its stack, and it wins whichever modality wins. - **Start contributing:** - [qua-libs](https://github.com/qua-platform/qua-libs) holds calibration and experiment libraries (Python, active 9 Nov). Format with `black`. An individual or corporate CLA is required (PDFs are in the repo). - [py-qua-tools](https://github.com/qua-platform/py-qua-tools) (active 21 Oct) has a contributing guide. - [quam](https://github.com/qua-platform/quam) is the machine-configuration framework (active 4 Nov). The QUAlibrate umbrella repo currently holds only a pointer file. **Links:** [Website](https://www.quantum-machines.co) · [X @QuantumQM](https://x.com/QuantumQM) · [GitHub](https://github.com/qua-platform). ### 22. Precilasers ($267M, STAR: 688826), adjacent - **Funding:** It raised CNY 1.87B in an Aug 2026 STAR IPO. - **Focus:** Narrow-linewidth lasers for atom and ion quantum computers, clocks and sensors. It is already profitable. - **Moat:** The leading domestic alternative to Toptica and NKT. - **Start contributing:** It has no public SDK. **Links:** [Website](https://www.precilasers.com). ### 25. Arqit Quantum ($240M, Nasdaq: ARQQ), adjacent - **Funding:** SPAC proceeds plus ATMs. It held \~$51M in cash at Sep 2026. - **Focus:** Software symmetric-key agreement marketed as quantum-safe, with a NATO consortium contract. - **Moat:** Thin. It brings in \~$1M a year of revenue and competes with standard post-quantum cryptography. - **Start contributing:** It has no public SDK. **Links:** [Website](https://arqit.uk). ### 27. CIQTEK ($240M, STAR: 688828), adjacent - **Funding:** It raised CNY 849M in an Aug 2026 IPO on top of \~CNY 0.8B private. - **Focus:** NV-diamond quantum sensors and EPR spectrometers. 56% of revenue comes from electron microscopes. - **Moat:** USTC spin-control heritage and the #2 global share in EPR. - **Start contributing:** Its repos are only instrument demos, such as an [AWG4100 Python API demo](https://github.com/CIQTEK/AWG4100_API_DEMO_PYTHON) from 2020. **Links:** [Website](https://www.ciqtek.com) · [GitHub](https://github.com/CIQTEK). ### 29. Classiq ($205M, private; Intel acquisition pending) - **Funding:** VC backers include Entree, Team8, SoftBank, AMD, Qualcomm and IonQ. Intel agreed in Oct 2026 to buy it for a reported \~$2.2–2.3B, expected to close in H1 2027. - **Focus:** A synthesis engine that turns high-level Qmod or Python models into optimized circuits for any backend. - **Moat:** Years of synthesis IP and a large algorithm library. It may lose some neutrality under Intel. - **Start contributing:** - [classiq-library](https://github.com/Classiq/classiq-library) holds 600+ algorithm notebooks and models (active 5 Nov). - Its guide asks you to link each PR to an issue, run `pre-commit`, and use the latest Classiq version. You can get help in GitHub Discussions or the Classiq Slack. - Adding a well-documented algorithm notebook is a realistic first PR. **Links:** [Website](https://www.classiq.io) · [X @classiqtech](https://x.com/classiqtech) · [GitHub](https://github.com/Classiq) · [Discussions](https://github.com/Classiq/classiq-library/discussions). **Programs:** It sponsored an iQuHACK 2026 challenge and has run its own [coding competitions](https://www.classiq.io/insights/classiq-coding-competition-inspires-new-generation-of-quantum-talent) ($25K prize pool in 2022). It also has a Slack community. ### 31. Horizon Quantum ($180M, Nasdaq: HQ) - **Funding:** \~$120M from its SPAC and PIPE, plus $28.7M in warrant exercises (Jun 2026). Backers include IonQ, Tencent and Peak XV. - **Focus:** Hardware-agnostic compilers: the Triple Alpha IDE and the Beryllium language. It runs its own Singapore testbed (the Ember-1 superconducting machine). - **Moat:** A pure-play listed software company that owns a multi-modality testbed. - **Start contributing:** It has no public repos. Beryllium is in early access. **Links:** [Website](https://www.horizonquantum.com) · [X @horizon\_quantum](https://x.com/horizon_quantum). ### 36. Sygaldry Technologies ($139M, private) - **Funding:** It raised a $105M Series A in Mar 2026 led by Breakthrough Energy Ventures. - **Focus:** Chad Rigetti's new company, building quantum-accelerated AI servers that combine matter qubits and photonics. It targets \~2030. - **Moat:** Founder credibility and alignment with AI infrastructure spending. - **Start contributing:** Only paper code is public ([tnwf-paper](https://github.com/sygaldry-tech/tnwf-paper), tensor-network generative models). **Links:** [Website](https://sygaldry.com) · [X @sygaldry\_tech](https://x.com/sygaldry_tech) · [GitHub](https://github.com/sygaldry-tech). ### 37. Q-CTRL ($130M, private) - **Funding:** Its Series B totals $113M, including a $59M B-2 in Oct 2024 (GP Bullhound, Airbus, Lockheed Martin Ventures). - **Focus:** Error-suppression software (Fire Opal), calibration automation (Boulder Opal) and quantum navigation (Ironstone Opal). - **Moat:** A decade of control-theory IP, and Fire Opal is embedded in the IBM, AWS and IonQ clouds. - **Start contributing:** [open-controls](https://github.com/qctrl/open-controls) is a library of dynamical-decoupling and pulse sequences (Python, active 26 Oct). Its commercial clients are not open source. **Links:** [Website](https://q-ctrl.com) · [X @qctrlHQ](https://x.com/qctrlHQ) · [GitHub](https://github.com/qctrl). ### 40. Riverlane ($120M, private) - **Funding:** It raised a $75M Series C in Aug 2024 (Planet First Partners). - **Focus:** Real-time QEC decoders on FPGA and ASIC (Deltaflow), at \~16µs end-to-end latency. Its goal is MegaQuOp machines before 2030. - **Moat:** A head start in decoder latency and hardware-agnostic distribution through control-stack partners. - **Start contributing:** This is the best entry into error correction. - [deltakit](https://github.com/Deltakit/deltakit) is an open QEC toolkit (Python, active 9 Nov). Look for `good first issue` and `help wanted`. Assigned issues get priority, so ask before starting unlabelled work. Run `uv sync`, then `uv run --group test pytest`. - [deltakit-stim](https://github.com/Deltakit/deltakit-stim) adds leakage-error modelling to Stim (C++ and Python). - [qeciphy](https://github.com/riverlane/qeciphy) is an FPGA-to-FPGA physical layer in SystemVerilog. It's a rare open-source quantum project for hardware engineers. **Links:** [Website](https://www.riverlane.com) · [X @RiverLane\_io](https://x.com/RiverLane_io) · [GitHub](https://github.com/Deltakit). **Programs:** The [Deltakit Community Fund](https://thequantuminsider.com/2026/07/28/riverlane-unitary-foundation-deltakit-community-fund/) pays $2,000–4,000 per feature, rolling quarterly, with discussion on the Unitary Foundation Discord. It's the only company-backed grant on this list aimed at open-source contributors. ## Big-tech quantum stacks: IBM, Google, Microsoft, AWS and NVIDIA The five big-tech programs raise no outside money for quantum, but they run the largest and most active open-source codebases. Every repo below had a commit in the last two weeks, except cuQuantum (Sep 2026) and Microsoft's archived katas. Expect a CLA or a sign-off rule, plus CI that is strict but well documented. ### 46. IBM Quantum (NYSE: IBM) - **Focus:** Superconducting Heron and Nighthawk processors, Loon for qLDPC codes (2025), and Starling, a fault-tolerant system with \~200 logical qubits targeted for 2029. - **Moat:** Qiskit is the most-used quantum SDK, and IBM has the largest fleet of cloud-accessible QPUs. - **Start contributing:** - [qiskit](https://github.com/Qiskit/qiskit) is the core SDK (Python with a growing Rust core and a C API). Install with `pip install -e .` and test with `tox -e py`. Use `cargo test` for Rust and `make ctest` for C. Sign the Qiskit CLA first. - [rustworkx](https://github.com/Qiskit/rustworkx) is a Rust graph library used well beyond quantum. It's a good on-ramp for Rust developers. - [qiskit-aer](https://github.com/Qiskit/qiskit-aer) is the C++ simulator. [qiskit-ibm-runtime](https://github.com/Qiskit/qiskit-ibm-runtime) handles hardware access. [qiskit-addon-sqd](https://github.com/Qiskit/qiskit-addon-sqd) does sample-based quantum diagonalization for chemistry. **Links:** [Website](https://www.ibm.com/quantum) · [GitHub](https://github.com/Qiskit). **Programs and community:** The [Open Plan](https://www.ibm.com/quantum/blog/open-plan-updates) gives 10 free QPU minutes every 28 days. [Qiskit Fall Fest](https://www.ibm.com/quantum/events/fall-fest-2026) runs student hackathons each autumn, and the [Qiskit Global Summer School](https://www.ibm.com/quantum/blog/qiskit-summer-school-2026) returned in 2026. The IBM Quantum Slack is at qisk.it/join-slack. ### 47. Google Quantum AI (Nasdaq: GOOGL) - **Focus:** The superconducting Willow chip (105 qubits), which showed below-threshold surface-code scaling in Dec 2024 and a verifiable "Quantum Echoes" result in Oct 2025. - **Moat:** Its error-correction research lead and Google-scale resources. Stim is the field's default QEC simulator. - **Start contributing:** Every quantumlib repo requires the Google CLA, signed once and covering all of them. - [Cirq](https://github.com/quantumlib/Cirq) is the core SDK (Python, active 9 Nov). - [Stim](https://github.com/quantumlib/Stim) is a fast stabilizer simulator (C++ with Python bindings). - [Qualtran](https://github.com/quantumlib/Qualtran) handles fault-tolerant algorithms and resource counts (Python). - [qsim](https://github.com/quantumlib/qsim) is a C++/CUDA simulator, [OpenFermion](https://github.com/quantumlib/OpenFermion) covers chemistry, and [ReCirq](https://github.com/quantumlib/ReCirq) reproduces Google's experiments. **Links:** [Website](https://quantumai.google) · [GitHub](https://github.com/quantumlib). ### 48. Microsoft Quantum (Nasdaq: MSFT) - **Focus:** Topological qubits (Majorana 1, Feb 2025, still contested) and Azure Quantum. Its "Level 2" logical-qubit systems are built with Atom Computing and others. - **Moat:** The software and error-correction layer for partner hardware, plus Azure distribution. - **Start contributing:** - [qdk](https://github.com/microsoft/qdk) (formerly microsoft/qsharp) holds the Q# compiler in Rust, the language service, the VS Code extension, the `qdk` Python package and the resource estimator (active 6 Nov). Its guide points to `good first issue` and `help wanted` labels. - [azure-quantum-python](https://github.com/microsoft/azure-quantum-python) handles job submission to partner hardware, including Atom Computing. - The old [QuantumKatas](https://github.com/microsoft/QuantumKatas) tutorials stopped in Jan 2024. The katas now live in the QDK. **Links:** [Website](https://quantum.microsoft.com) · [GitHub](https://github.com/microsoft/qdk). **Programs:** On [Azure Quantum](https://learn.microsoft.com/azure/quantum/pricing), the IonQ simulator and Rigetti QVM are free, and the resource estimator runs locally at no cost. ### 49. AWS / Amazon Braket (Nasdaq: AMZN) - **Focus:** Braket offers multi-vendor cloud access to IonQ, Rigetti, IQM, QuEra and others. In Feb 2025 it unveiled Ocelot, its own cat-qubit chip. - **Moat:** Distribution, since it's the default procurement path for enterprises already on AWS. - **Start contributing:** - [amazon-braket-sdk-python](https://github.com/amazon-braket/amazon-braket-sdk-python) is the SDK (active 9 Nov). Run `pip install tox`, then `tox -e unit-tests`. - [amazon-braket-examples](https://github.com/amazon-braket/amazon-braket-examples) is the easiest first PR. A CLA may be requested for larger changes. - [autoqasm](https://github.com/amazon-braket/autoqasm) writes OpenQASM programs in Python, and [amazon-braket-default-simulator-python](https://github.com/amazon-braket/amazon-braket-default-simulator-python) is the local simulator. **Links:** [Website](https://aws.amazon.com/braket/) · [GitHub](https://github.com/amazon-braket). **Programs:** The [free tier](https://aws.amazon.com/braket/pricing/) includes 1 hour of simulator time a month for 12 months. Braket Direct sells reserved QPU time. ### 50. NVIDIA (Nasdaq: NVDA) - **Focus:** GPU acceleration for simulation, QEC decoding and hybrid control. That includes CUDA-Q, NVQLink (Oct 2025) and the NVAQC research centre in Boston. NVentures holds stakes in PsiQuantum, Quantinuum, QuEra and Alice & Bob. - **Moat:** Every hardware roadmap needs classical compute beside the QPU, and NVIDIA is becoming that default. - **Start contributing:** - [cuda-quantum](https://github.com/NVIDIA/cuda-quantum) is the hybrid programming model and compiler (C++ and Python, active 9 Nov). Every commit needs a DCO sign-off (`git commit -s`). Install `pre-commit` and run the hooks before pushing. - [cudaqx](https://github.com/NVIDIA/cudaqx) provides QEC and solver libraries built on CUDA-Q (active 7 Nov). - [cuQuantum](https://github.com/NVIDIA/cuQuantum) has the Python bindings and samples for GPU state-vector and tensor-network simulation. **Links:** [Website](https://developer.nvidia.com/cuda-q) · [GitHub](https://github.com/NVIDIA/cuda-quantum) · [CUDA-Q blog](https://nvidia.github.io/cuda-quantum/blogs/blog/). **Programs:** It sponsored an iQuHACK 2026 challenge. Universities can join the CUDA-Q academic program ([example](https://mdh.se/en/malardalen-university/articles/archive/2024-04-18-mdu-joins-nvidia-cuda-q-academic-program)) and apply to the [NVIDIA Academic Grant Program](https://www.vanderbilt.edu/cttc/nvidia-academic-grant-program-simulation-and-modeling/) for compute. ## How to start contributing to quantum open source, by skill Pick the repo that matches the skill you already have, land one docs or test PR, then use a bounty, grant or free-credit program to go deeper. ### By skill 1. **New to quantum:** Start with notebook and docs PRs to [PennyLane demos](https://github.com/PennyLaneAI/demos), [classiq-library](https://github.com/Classiq/classiq-library) or [amazon-braket-examples](https://github.com/amazon-braket/amazon-braket-examples). They're the lowest-friction first merges. 2. **Python developer:** Hardware providers and SDKs: [qiskit-ionq](https://github.com/qiskit-community/qiskit-ionq), [qiskit-alice-bob-provider](https://github.com/Alice-Bob-SW/qiskit-alice-bob-provider), [client-superstaq](https://github.com/Infleqtion/client-superstaq), [Pulser](https://github.com/pasqal-io/Pulser), [bloqade-circuit](https://github.com/QuEraComputing/bloqade-circuit), [dimod](https://github.com/dwavesystems/dimod), [pyquil](https://github.com/rigetti/pyquil), [qat](https://github.com/oqc-community/qat), [Perceval](https://github.com/Quandela/Perceval). 3. **Rust or C++ developer:** Compilers and simulators, where skilled contributors are scarcest. In Rust: the [Qiskit](https://github.com/Qiskit/qiskit) Rust core, [rustworkx](https://github.com/Qiskit/rustworkx), [hugr](https://github.com/quantinuum/hugr) and the [qdk](https://github.com/microsoft/qdk) compiler. In C++: [tket](https://github.com/quantinuum/tket), [Stim](https://github.com/quantumlib/Stim), [cuda-quantum](https://github.com/NVIDIA/cuda-quantum), [pennylane-lightning](https://github.com/PennyLaneAI/pennylane-lightning) and [dwave-optimization](https://github.com/dwavesystems/dwave-optimization). 4. **Error correction and fault-tolerant algorithms:** [deltakit](https://github.com/Deltakit/deltakit), [Stim](https://github.com/quantumlib/Stim), [Qualtran](https://github.com/quantumlib/Qualtran), [qLDPC](https://github.com/qLDPCOrg/qLDPC), [tsim](https://github.com/QuEraComputing/tsim), [bartiq](https://github.com/PsiQ/bartiq), [anb-estimator](https://github.com/Alice-Bob-SW/anb-estimator), [cudaqx](https://github.com/NVIDIA/cudaqx). 5. **Hardware, FPGA or physics:** [KQCircuits](https://github.com/iqm-finland/KQCircuits) for chip layout, [qeciphy](https://github.com/riverlane/qeciphy) (SystemVerilog), [qua-libs](https://github.com/qua-platform/qua-libs) for calibration, [open-controls](https://github.com/qctrl/open-controls) for pulse sequences, and [SpinPulse](https://github.com/quobly-sw/SpinPulse) for spin qubits. 6. **Unusual languages:** [quilc](https://github.com/quil-lang/quilc) and [qvm](https://github.com/quil-lang/qvm) in Common Lisp, and [Bloqade.jl](https://github.com/QuEraComputing/Bloqade.jl) in Julia. ### Quantum hackathons, grants and free credits in 2026 | Program | Run by | What you get | When | | --- | --- | --- | --- | | [unitaryHACK](https://thequantuminsider.com/2026/05/30/open-source-quantum-community-prepares-for-sixth-annual-unitaryhack/) | Unitary Foundation | Cash bounties for merged fixes on participating repos, including [PennyLane](https://pennylane.ai/blog/2026/05/claim-bounties-from-pennylane-in-unitaryhack-2026/). The 2025 edition paid out 172 bounties worth $19,000+ | Yearly, 3–17 Jun in 2026 | | [Unitary Foundation microgrant](https://www.startupgrantsindia.com/unitary-foundation-microgrant) | Unitary Foundation | $4,000 for open-source quantum software, education or hardware. No affiliation needed | Rolling | | [Deltakit Community Fund](https://thequantuminsider.com/2026/07/28/riverlane-unitary-foundation-deltakit-community-fund/) | Riverlane + Unitary Foundation | $2,000–4,000 per Deltakit feature (error budgets, thresholds, ZX benchmarks). Excludes EAR/OFAC-restricted countries | Quarterly, first cohort reviewed from 17 Aug 2026 | | [QHack Coding Challenge](https://pennylane.ai/blog/2026/08/september-events) | Xanadu (PennyLane) | Coding championship with cash prizes | 16–23 Oct 2026, yearly | | [iQuHACK](https://qbraid.com/blog-posts/qbraid-iquhack-2026) | MIT | Challenges from NVIDIA, IonQ, IQM, QuEra, Alice & Bob, Nord Quantique, Classiq and others | Yearly, 30 Jan–1 Feb in 2026 | | [SG Grand Challenge](https://quantumzeitgeist.com/quantinuum-quantum-challenge-computing-solutions/) | Quantinuum | Three-month program with a finals event in Singapore | Launched Jul 2026 | | [Qiskit Fall Fest](https://www.ibm.com/quantum/events/fall-fest-2026) | IBM + universities | Student-run workshops and hackathons, in person and virtual | Oct–Nov 2026 | | [IonQ Research Credits](https://ionq.com/programs/research-credits) | IonQ | Up to $10,000 of QPU time for academics | By proposal | | [IBM Quantum Open Plan](https://www.ibm.com/quantum/blog/open-plan-updates) | IBM | 10 min of QPU time every 28 days on a Heron r2 system. After 20 min used, a one-time 180-min offer | Ongoing | | [Amazon Braket free tier](https://aws.amazon.com/braket/pricing/) | AWS | 1 hour of simulator time per month for your first 12 months | Ongoing | | [IQM Resonance Starter](https://quantumzeitgeist.com/iqm-boosts-cloud-platform-with-54-qubit-system-free-tier/) | IQM | Up to 30 credits a month on selected IQM QPUs | Ongoing | | [D-Wave Leap](https://support.dwavesys.com/hc/en-us/articles/360003680734) | D-Wave | A trial plan for running demos, plus community forums | Ongoing | | [Azure Quantum](https://learn.microsoft.com/azure/quantum/pricing) | Microsoft | IonQ's simulator and Rigetti's QVM are free on pay-as-you-go | Ongoing | | [Brisbane Undergraduate Mentorship](https://www.psiquantum.com/australia-undergrad-mentorship-2026) | PsiQuantum | Free mentoring and lab visits for Queensland undergraduates | Sep–Oct 2026 | The unitaryHACK bounty list and the Deltakit fund are the most direct ways to get paid for open-source quantum work. ## FAQ **Which quantum computing company has raised the most money?** IonQ, with about $6.1B of equity by Nov 2026, including a $2.0B offering in October. Quantinuum is second at \~$2.9B after its $1.68B IPO in June 2026. **Which quantum companies have the best open-source projects to contribute to?** Among startups, it's Xanadu (PennyLane), Quantinuum (TKET, Guppy, HUGR), QuEra (Bloqade, Kirin), D-Wave (Ocean) and Pasqal (Pulser). Among big tech, it's IBM's Qiskit, Google's Cirq and Stim, and NVIDIA's CUDA-Q. **Can you get paid to contribute to quantum open source?** Yes. unitaryHACK paid out 172 bounties worth $19,000+ in 2025. The Unitary Foundation gives $4,000 microgrants, and the Deltakit Community Fund pays $2,000–4,000 per feature. **Can I run code on a real quantum computer for free?** Yes. IBM's Open Plan gives 10 QPU minutes every 28 days, IQM Resonance has a free Starter tier, and IonQ offers academics up to $10,000 in credits. **What language should I learn for quantum computing?** Python covers almost every SDK. Rust and C++ are where compilers and simulators most need help: Qiskit's core, the Q# compiler, TKET, Stim and CUDA-Q. ## About the author Siddharth Lalwani is a quantum computing enthusiast building at the edge of adoption: bringing NISQ-era quantum solutions into real enterprise workflows. He is Co-Founder and CEO of Skate and was previously a Venture Partner at Nomad Capital. X: https://x.com/alt_v0rtex · Email: dev@almond.org ## Sources - Funding, moat, roadmap and X data: Almond Labs' Notion databases *Quantum Companies That Raised $100M+: Deep Dive* and *Quantum Computing: Best-Capitalized Companies* (both 9 Nov 2026), which cite the company filings and press for each figure. - Repository activity, contributing guides, CLAs and languages: a direct scan of each linked GitHub repository's default branch on 10 Nov 2026. - [IBM: Open Plan updates](https://www.ibm.com/quantum/blog/open-plan-updates) · [Qiskit Fall Fest 2026](https://www.ibm.com/quantum/events/fall-fest-2026) - [Amazon Braket pricing](https://aws.amazon.com/braket/pricing/) · [Azure Quantum pricing](https://learn.microsoft.com/azure/quantum/pricing) - [IonQ Research Credits](https://ionq.com/programs/research-credits) · [D-Wave Leap sign-up](https://support.dwavesys.com/hc/en-us/articles/360003680734) · [IQM Resonance free tier](https://quantumzeitgeist.com/iqm-boosts-cloud-platform-with-54-qubit-system-free-tier/) - [PennyLane September 2026 events](https://pennylane.ai/blog/2026/08/september-events) · [PennyLane in unitaryHACK 2026](https://pennylane.ai/blog/2026/05/claim-bounties-from-pennylane-in-unitaryhack-2026/) - [unitaryHACK 2026 (The Quantum Insider)](https://thequantuminsider.com/2026/05/30/open-source-quantum-community-prepares-for-sixth-annual-unitaryhack/) · [Deltakit Community Fund](https://thequantuminsider.com/2026/07/28/riverlane-unitary-foundation-deltakit-community-fund/) · [Unitary Foundation microgrant](https://www.startupgrantsindia.com/unitary-foundation-microgrant) - [iQuHACK 2026 (qBraid)](https://qbraid.com/blog-posts/qbraid-iquhack-2026) · [Quantinuum SG Grand Challenge](https://quantumzeitgeist.com/quantinuum-quantum-challenge-computing-solutions/) · [PsiQuantum Brisbane mentorship](https://www.psiquantum.com/australia-undergrad-mentorship-2026) - [Pasqal community](https://pasqal.com/?p=360) · [Classiq coding competition](https://www.classiq.io/insights/classiq-coding-competition-inspires-new-generation-of-quantum-talent)