Slint
Slint (SixtyFPS GmbH) provides a declarative GUI toolkit that compiles to native code for embedded, desktop, and mobile apps, with sub-300KiB runtime and bindings for Rust, C++, JavaScript, and Python, monetizing via commercial licensing and embedded unit royalties.
- Company typePrivate
- Founded2021
- HeadquartersHohen Neuendorf, Germany
- Headcount1–10
- GTM typeB2B
- OfferingSoftware
What Slint does
Slint, operated by SixtyFPS GmbH and headquartered in Hohen Neuendorf (with copyright references in Munich), Germany, is a developer-tools company that provides a declarative GUI toolkit for building native user interfaces across embedded, desktop, and mobile platforms. The product centers on a domain-specific language (.slint) resembling HTML/CSS that compiles to native machine code and ships with a runtime footprint under 300KiB RAM, enabling deployment on resource-constrained microcontrollers including ESP32 and STM32 boards. Business logic can be implemented in Rust, C++, JavaScript, or Python, and the framework supports multiple rendering backends (Qt, Winit, LinuxKMS, Skia, FemtoVG, and a portable software renderer). The product portfolio comprises the Slint UI framework, language-specific APIs, the SlintPad browser-based editor, a VS Code extension with Live-Preview, a Figma-to-Slint design integration, and a Material 3 component library.
Slint monetizes through a tiered licensing structure: GPLv3 and Community licenses are free, while a Royalty-Free license, Enterprise agreements, and an Embedded Systems add-on (priced at $100-$500/month or on a per-unit usage/buyout basis) generate commercial revenue. Recurring Standard Support subscriptions and a GUI Test Automation framework add-on supplement license revenue. The go-to-market is product-led, with self-service adoption through GitHub (20k+ stars, 195 contributors, 2k+ community projects), SlintPad, and package registries (crates.io, npm, pip, ESP-IDF). Enterprise and complex embedded deployments are routed through direct sales and an implementation partner network that includes KDAB, tQCS, Spyrosoft, and silicon/board partners such as Espressif, ST Microelectronics, Raspberry Pi, Toradex, QNX, Yocto, and Zephyr.
Named customers include SK Signet (EV chargers), OTIV (rail automation), WesAudio and Aava (audio plugins), Nexter Robotics, Jasic Technology Europe, CRP Robot, and Arc Vehicle. The company is a Silver Member of the Rust Foundation and was co-founded by Olivier Goffart, Aurindam Jana, and Simon Hausmann. As of the latest input data, Slint remains a privately-held company with 1-10 employees and no publicly disclosed funding rounds or revenue figures.
Slint firmographics
Firmographics- Name
- Slint
- Legal name
- SixtyFPS GmbH
- Website
- https://slint.dev
- Company type
- Private
- Founded year
- 2021
- Operating status
- Operating
- Headcount range
- 1–10 employees
- Short description
- Slint (SixtyFPS GmbH) provides a declarative GUI toolkit that compiles to native code for embedded, desktop, and mobile apps, with sub-300KiB runtime and bindings for Rust, C++, JavaScript, and Python, monetizing via commercial licensing and embedded unit royalties.
- Ownership category
- akta.pro rank
Where Slint is headquartered
LocationHeadquarters
- HQ city
- Hohen Neuendorf
- HQ country
- Germany
- HQ region
- Europe
Offices1 record
Markets served
Slint business model
Business model- GTM type
- B2B
- Offering type
- Software
- Cost components
- Technology or R&D, Personnel, Marketing or Sales, Operations
Revenue model
- Software Licenses: Slint offers multiple licensing tiers including GPLv3 for open source projects, Royalty-Free permissive license for commercial desktop/mobile/web development, and Seat licenses for teams needing to avoid copyleft obligations. Enterprise licensing is available for larger deployments.
- Subscription Support: Standard support subscription including technical queries, troubleshooting, and bug resolution for the latest stable release. Perpetual fallback license allows continued use of specific versions without active subscription after 12 months of paid subscription.
- Embedded Systems Royalties: Additional fees for deploying on embedded systems. Options include buyout plans (10,000 units minimum with 20% discount), usage-based monthly billing, or annual pre-purchase (2,000 units with minimum 5% discount).
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Freemium | Annual | GPLv3 License - Free for open source projects |
| Freemium | Annual | Community License - Free for desktop/mobile/web |
| Subscription | Monthly | Royalty-Free License - Commercial use without royalties |
| Subscription | Multi-year contract | Enterprise License - Custom commercial licensing |
| Unit Pricing | Monthly | Embedded Systems Add-on |
| Subscription | Monthly | Standard Support Add-on |
| One time/ perpetual license | Multi-year contract | Perpetual Fallback License Add-on |
| Subscription | Monthly | GUI Test Framework Add-on |
Go-to-market motion1 record
Distribution channels5 records
Marketing channels9 records
Slint product offering
Product offeringCore offering
Slint is a declarative GUI toolkit that compiles user interface definitions written in its domain-specific language (.slint files) to native machine code, targeting embedded, desktop, and mobile platforms. The framework provides multi-language bindings for Rust, C++, JavaScript, and Python, with a runtime footprint under 300KiB RAM. Slint offers commercial licensing (Royalty-Free, Enterprise, embedded royalties), developer tools (Live-Preview, VS Code extension, Figma plugin), and a Material 3 component library.
Product overview
Slint is a declarative GUI toolkit offered as a single unified product with multiple language bindings. The core is the Slint UI Framework, which uses the Slint DSL (.slint files) to describe user interfaces. The product includes IDE tooling (VS Code Extension with Live-Preview), design integration (Figma to Slint Plugin), and pre-built components (Material 3). Developers can use their preferred language—Rust, C++, JavaScript, or Python—to implement business logic while using Slint's DSL for UI definition. The framework compiles to native machine code and targets embedded systems, desktop, mobile, and web platforms.
Differentiator
Problem solved
Functional benefit
Quantifiable outcome
- Runtime fits in less than 300KiB RAM
- +3 more outcomes
Companies that use Slint
Customer profileNamed customers8 records
Segments6 records
Ideal customer profiles4 records
Slint technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- Yes
- API docs
- API detail
Core technology
AI maturity
App detail
Integration1 record
Feature10 records
Slint partnerships and signals
Strategic signalPartnerships
Eight partnerships are on record, tiered core and minor.
- KDABcoreKDAB collaborated on the SK Signet EV charger project, providing expertise in porting from Qt to Slint. Based on this experience, KDAB initiated R&D to combine their tools (KDBindings, KDUtils) with C++ ecosystem libraries into a coherent package for C++ application development without Qt.
- tQCScoretQCS collaborated with Slint on the SK Signet EV charger HMI project, providing implementation support for the next-generation charger interface.
- SpyrosoftcoreSpyrosoft collaborated on the WesAudio DAW plugin redesign project, implementing the Slint-based UI for digital audio workstation plugins.
- Rust Foundation (Silver Member)minorSlint is a Silver Member of the Rust Foundation, supporting the Rust programming language ecosystem that Slint is built upon.
- CrosswareminorListed in Slint's global partner network.
- Cynetics EmbeddedminorListed in Slint's global partner network.
- ExtenlyminorListed in Slint's global partner network.
- FelgominorListed in Slint's global partner network.
Scale indicators3 records
Recent moves6 records
Expansion highlights6 records
Slint competitors and assessment
Company assessmentBroad incumbents
- React Native: React Native is a broad-incumbent cross-platform mobile UI framework from Meta. It competes for mobile/embedded developer mindshare and is often the default starting point for teams evaluating Slint for mobile/embedded UIs.
- Electron: Electron is the incumbent cross-platform desktop framework using Chromium/Node. Slint explicitly markets against Electron's overhead (large bundle, high memory), targeting developers who need native performance without the Chromium footprint.
Emerging players
- Tauri: Tauri is a Rust-based framework for building cross-platform desktop apps using webview frontends. It is an emerging alternative for desktop use cases where developers want a Rust toolchain and small footprint, but lacks Slint's embedded reach.
- egui (emilk/egui): egui is a popular immediate-mode Rust GUI library widely used for tools, prototypes, and embedded demos. It overlaps with Slint's Rust developer audience but lacks Slint's retained-mode, declarative DSL and commercial licensing path.
- Dear ImGui: Dear ImGui is the de facto immediate-mode C++ GUI library for tools, game editors, and embedded debug UIs. It is a free, ubiquitous alternative for many of Slint's C++/embedded use cases, though without Slint's declarative tooling.
Direct peers
- LVGL: LVGL is a lightweight open-source embedded graphics library targeting microcontrollers and resource-constrained devices. It overlaps with Slint's embedded/HMI focus and competes for design wins on MCUs and industrial panels.
- Flutter (Google): Flutter is a cross-platform declarative UI toolkit targeting mobile, desktop, web, and embedded from a single codebase. While Dart-based and heavier than Slint, it competes for the same cross-platform developer mindshare and embedded HMI design wins.
- The Qt Company: Qt is the dominant commercial cross-platform UI framework with deep embedded/automotive adoption. Slint explicitly positions as a modern, lightweight alternative for Qt QML migrations, and ships a Qt backend for drop-in compatibility, making Qt the single most direct comparable.
- TouchGFX (STMicroelectronics): TouchGFX is an embedded GUI framework bundled with STM32 microcontrollers, serving the same embedded HMI developer audience. It competes for STM32-based design wins where Slint also has board support.
- Avalonia UI: Avalonia is a cross-platform .NET-based declarative UI framework for desktop, mobile, and embedded, offering a commercial open-source model similar to Slint. It is a direct competitor for cross-platform native UIs outside the Rust/C++ ecosystem.
Market position
Strengths1 record
Weaknesses5 records
Competitive moat5 records
Key risks7 records
Key highlights7 records
Customer concentration
Slint social profiles
Digital presenceSlint financial estimates
Financial estimateRevenue estimate
Valuation estimate
Slint leadership team
Management profileNumber of profiles
Profiles3 records
Slint funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Slint M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Slint
What does Slint do?
Slint is a declarative GUI toolkit that compiles user interface definitions written in its domain-specific language (.slint files) to native machine code, targeting embedded, desktop, and mobile platforms. The framework provides multi-language bindings for Rust, C++, JavaScript, and Python, with a runtime footprint under 300KiB RAM. Slint offers commercial licensing (Royalty-Free, Enterprise, embedded royalties), developer tools (Live-Preview, VS Code extension, Figma plugin), and a Material 3 component library.
Is Slint a public or private company?
Slint is a private company. It is classified as unknown and is currently operating.
When was Slint founded?
Slint was founded in 2021. It employs 1 to 10 people.
Where is Slint based?
Slint is headquartered in Hohen Neuendorf, Germany, in the Europe region.
How does Slint make money?
Three revenue lines are on record. Software Licenses are the primary driver. The others are subscription Support and embedded Systems Royalties.
Who are Slint's main competitors?
Broad incumbents on record are React Native and Electron. Emerging players are Tauri, egui (emilk/egui) and Dear ImGui. Direct peers are LVGL, Flutter (Google), The Qt Company, TouchGFX (STMicroelectronics) and Avalonia UI.
Does Slint have an API?
Yes. Slint provides a comprehensive API for multiple programming languages including Rust, C++, JavaScript, and Python. The API allows developers to build graphical user interfaces using Slint's declarative DSL (.slint files) combined with business logic in their preferred language. Public APIs include Rust API (https://docs.slint.dev/latest/docs/rust/slint), C++ API (https://docs.slint.dev/latest/docs/cpp), Node.js API (beta), and Python API. Developer documentation is at docs.slint.dev.