TL;DR: OpenSpec is a Y Combinator Winter 2026 startup Plan mode for complex features, currently active with an early-stage team.
Plan mode for complex features
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OpenSpec is an open-source, spec-driven framework. We help developers plan complex features by creating lightweight spec documents that serve as durable context for their coding agents. With 20k+ GitHub stars, we’re one of the leading spec-driven frameworks, used by thousands of developers and teams to plan and ship with the coding agent of their choice. Our philosophy is simple: keep planning lightweight and iterative, and match how software actually gets built, messy, evolving, and real, without dragging teams into rigid, bureaucratic workflows.
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Yes. OpenSpec was funded by Y Combinator in the Winter 2026 batch. Plan mode for complex features
OpenSpec is an open-source, spec-driven framework. We help developers plan complex features by creating lightweight spec documents that serve as durable context for their coding agents. With 20k+ GitHub stars, we’re one of the leading spec-driven frameworks, used by thousands of developers and teams to plan and ship w…
OpenSpec was part of Y Combinator's Winter 2026 batch.
OpenSpec is currently listed as Active in Y Combinator's directory.
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