A system comprising: a network controller for a virtualized computing infrastructure, wherein the network controller is configured to: receive a request for a service chain comprising one or more service instances for the service chain; install, to a server of the virtualized computing infrastructure, an egress service instance of the one or more service instances for the service chain; and a scalable service platform, wherein the scalable service platform comprises one or more virtual routers executing on a set of one or more servers, and wherein the one or more virtual routers are configured to create, in response to receiving a forward packet flow from the server hosting the egress service instance, a flow table entry for a reverse packet flow corresponding to the forward packet flow, wherein the flow table entry specifies the server hosting the egress service instance as a next hop for the reverse packet flow, wherein the one or more virtual routers are configured to forward, based on the flow table entry, the reverse packet flow to the server; install the one or more service instances (302, 304, 306) for the service chain to one or more servers of the virtualized computing infrastructure, the one or more service instances (302, 304, 306) including the egress service instance; install, to the set of one or more servers of the scalable service platform, a first service instance for an ingress of the service chain; and install, to the set of one or more servers of the scalable service platform, a second service instance for an egress of the service chain, wherein the first service instance and second service instance operate as endpoints for the service chain to anchor packet flows mapped to the service chain. a network controller for a virtualized computing infrastructure, wherein the network controller is configured to: receive a request for a service chain comprising one or more service instances for the service chain; install, to a server of the virtualized computing infrastructure, an egress service instance of the one or more service instances for the service chain; and receive a request for a service chain comprising one or more service instances for the service chain; install, to a server of the virtualized computing infrastructure, an egress service instance of the one or more service instances for the service chain; and a scalable service platform, wherein the scalable service platform comprises one or more virtual routers executing on a set of one or more servers, and wherein the one or more virtual routers are configured to create, in response to receiving a forward packet flow from the server hosting the egress service instance, a flow table entry for a reverse packet flow corresponding to the forward packet flow, wherein the flow table entry specifies the server hosting the egress service instance as a next hop for the reverse packet flow, wherein the one or more virtual routers are configured to forward, based on the flow table entry, the reverse packet flow to the server; install the one or more service instances (302, 304, 306) for the service chain to one or more servers of the virtualized computing infrastructure, the one or more service instances (302, 304, 306) including the egress service instance; install, to the set of one or more servers of the scalable service platform, a first service instance for an ingress of the service chain; and install, to the set of one or more servers of the scalable service platform, a second service instance for an egress of the service chain, wherein the first service instance and second service instance operate as endpoints for the service chain to anchor packet flows mapped to the service chain.